Iridium complex compound, iridium complex compound-containing composition, organic electroluminescent device and method for producing the same, organic EL display device, and organic EL lighting device

Abstract

The present invention relates to an iridium complex compound represented by formula (1) (in formula (1), Ir represents an iridium atom, R5 to R14, R21, and R22 each independently represent a hydrogen atom, D, F, Cl, Br, I, or a substituent group, groups adjacent to each other may further bond to form a ring, and either R12 or R13 is a substituent group represented by formula (2)).

Description

[Technical field]

[0001] The present invention relates to an iridium complex compound, and in particular to an iridium complex compound useful as a material for a light-emitting layer of an organic electroluminescent (hereinafter, sometimes referred to as "organic EL") element, an iridium complex compound-containing composition containing the compound and a solvent, an organic electroluminescent element containing the compound and a method for producing the same, and an organic EL display device and an organic EL lighting device each having the organic electroluminescent element. [Background technology]

[0002] Various electronic devices that use organic EL elements, such as organic EL lighting and organic EL displays (display devices), are being put to practical use. Organic electroluminescent elements consume little power due to the low applied voltage, and are capable of emitting the three primary colors, so they are beginning to be used not only in large display monitors, but also in small and medium-sized displays such as those used in mobile phones and smartphones. Organic electroluminescent devices are manufactured by stacking multiple layers such as a light-emitting layer, a charge injection layer, and a charge transport layer. Currently, most organic electroluminescent devices are manufactured by evaporating organic materials under vacuum, but the vacuum deposition method makes the deposition process complicated and has poor productivity. In addition, it is extremely difficult to enlarge the panels of lighting and displays with organic electroluminescent devices manufactured by the vacuum deposition method. Therefore, in recent years, wet film-forming coating methods, which are coating methods, have been actively researched as a process for efficiently manufacturing organic electroluminescent devices that can be used for large displays and lighting. The wet film-forming method has the advantage of being able to easily form a stable layer compared to the vacuum deposition method, and is therefore expected to be applied to mass production of displays and lighting devices and large devices.

[0003] In order to manufacture organic electroluminescent devices using the wet film-forming method, all materials used must be able to dissolve in organic solvents and be used as ink. If the materials used have poor solvent solubility, they may deteriorate before use because they require long-term heating or other operations. Furthermore, if the materials cannot be kept in a homogeneous state for a long time in the solution state, they will precipitate from the solution, making it impossible to form a film using an inkjet device or the like. In other words, materials used in the wet film-forming method are required to be soluble in two senses: they must be quickly dissolved in organic solvents, and they must be able to maintain a homogeneous state after dissolving without precipitating.

[0004] Meanwhile, organic EL displays are required to realize high luminous efficiency in addition to a long operating life and a wide color gamut, i.e., high color reproduction rate. In particular, a fairly deep red color with an x ​​coordinate of 0.68 to 0.71 in the CIE (International Commission on Illumination) XYZ color coordinate system is required for the red region. In order to produce a deep red color, the maximum emission wavelength of the luminescent material must be longer, for example, 615 nm or longer. In addition, since the visual sensitivity of humans also decreases significantly as the wavelength becomes longer in the red region, a greater emission intensity is required in the deep red region.

[0005] In addition, there are two types of stacked structure for organic EL displays, which differ in the direction of light extraction. The bottom emission type, which is considered to have a relatively simple manufacturing process, extracts the light of organic molecules from the bottom of the TFT (thin film transistor) substrate side, but has the drawback of low light utilization efficiency of organic molecules. In contrast, the top emission type extracts light from above the sealing glass where there are no pixel circuits, so the emitted light can be efficiently extracted to the outside. However, when using the top emission type, light other than a specific wavelength is reflected and canceled out within the stacked structure, resulting in a property that it does not leave the stacked structure. For this reason, if the half-width of the emission spectrum of the light-emitting material is large, light other than the specific wavelength does not leave the stacked structure, resulting in a decrease in the efficiency of light emission. Therefore, narrowing the half-width of the emission spectrum even a little is preferable for making displays wider in color gamut and higher in brightness, and is a very important goal of technological development.

[0006] As mentioned above, red light-emitting materials are required to have the following properties: 1. high solubility in solvents, 2. high luminous efficiency, and 3. narrow half-width of the emission spectrum. Regarding 1, a technique is known in which the structure is not too rigid, such as by increasing the number of condensed rings in the ligand, and relatively long-chain alkyl groups are introduced. Regarding 2, the so-called "energy gap rule" is dominant in the red region, and as the wavelength becomes longer, the proportion of light dissipated into heat increases, so there is an upper limit to the quantum yield at a specific wavelength. In response to this, techniques have been clarified in recent years, such as using phosphorescent materials that are originally highly efficient, eliminating substituents that impair the quantum yield of these materials, increasing the symmetry of the structure, and increasing the MLCT (Metal to Ligand Charge Transfer) property to increase the phosphorescence emission rate.

[0007] As a red light emitting material, an iridium complex compound utilizing phosphorescence has been used. In particular, an iridium complex compound having a ligand in which a triazine type substituent is introduced into a phenyl-pyridine as shown in Patent Documents 1 to 3 is known. Patent Document 1 discloses an iridium complex compound having a specific structure. Similarly, Patent Documents 2 and 3 disclose an iridium complex compound having a specific structure. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] International Publication No. 2015 / 105014 [Patent Document 2] US Patent Application Publication No. 2016 / 359122 [Patent Document 3] International Publication No. 2016 / 015815 Summary of the Invention [Problem to be solved by the invention]

[0009] On the other hand, knowledge regarding the issue of narrowing the half-width of the emission spectrum mentioned in 3. above is not yet sufficient. For example, Patent Document 1 discloses an iridium complex compound having a structure in which two aromatic rings are bonded to triazine, but there is room for improvement in the half-value width. Furthermore, the so-called heteroleptic iridium complex, which has asymmetric ligands as disclosed in Patent Document 2, also has the problem of a broadened half-width. Patent Document 3 discloses an iridium complex compound that emits red light with a relatively narrow half-width, but it is believed that there is still room for improvement.

[0010] An object of the present invention is to provide an iridium complex compound that has a half-width as narrow as possible while at the same time maintaining high solubility in a solvent and high luminous efficiency. [Means for solving the problem]

[0011] Examples of iridium complex compounds that solve the above problems are as follows: [1] An iridium complex compound represented by the following formula (1):

[0012] [ka]

[0013] [In formula (1), Ir represents an iridium atom. 5 ~R 14 , R 21 and R 22 each independently represents a hydrogen atom, D, F, Cl, Br, I, or a substituent. Adjacent groups may be further bonded to form a ring. However, R 12 and R 13 Any one of the above is a substituent represented by the following formula (2).

[0014] [ka]

[0015] [In formula (2), the dashed line represents a bond to formula (1). R 31 represents a hydrogen atom, D, an alkyl group, an aralkyl group, or a heteroaralkyl group; R 32 R represents a hydrogen atom, D, an alkyl group, an aralkyl group, a heteroaralkyl group, an aromatic group, or a heteroaromatic group. 31 and R 32 may be further substituted.

[0016] [2] R in the above formula (1) 5 ~R 14 , R 21 and R 22 The iridium complex compound according to the above [1], [R 5 ~R 14 , R 21 and R 22each independently represents a hydrogen atom, D, F, Cl, Br, I, -N(R')2, -CN, -NO2, -OH, -COOR', -C(=O)R', -C(=O)NR', ​​-P(=O)(R')2, -S(=O)R', -S(=O)2R', -OS(=O)2R', a linear or branched alkyl group having from 1 to 30 carbon atoms, a cyclic alkyl group having from 3 to 30 carbon atoms, a linear or branched alkoxy group having from 1 to 30 carbon atoms, a cyclic alkoxy group having from 2 to 30 carbon atoms, a linear or branched alkylthio group having from 1 to 30 carbon atoms, a cyclic alkylthio group having from 2 to 30 carbon atoms, a linear or branched alkyl group having from 2 to 30 carbon atoms, or a branched alkenyl group, a cyclic alkenyl group having 3 to 30 carbon atoms, a linear or branched alkynyl group having 2 to 30 carbon atoms, a cyclic alkynyl group having 3 to 30 carbon atoms, an aromatic group having 5 to 60 carbon atoms, a heteroaromatic group having 1 to 60 carbon atoms, an aryloxy group having 5 to 40 carbon atoms, an arylthio group having 5 to 40 carbon atoms, an aralkyl group having 5 to 60 carbon atoms, a heteroaralkyl group having 2 to 60 carbon atoms, a diarylamino group having 10 to 40 carbon atoms, an arylheteroarylamino group having 10 to 40 carbon atoms, or a diheteroarylamino group having 10 to 40 carbon atoms.

[0017] In the alkyl group, the alkoxy group, the alkylthio group, the alkenyl group and the alkynyl group, at least one or more hydrogen atoms may be further substituted with R' (excluding hydrogen atoms), and one -CH2- group or two or more non-adjacent -CH2- groups in these groups may be substituted with -C(-R')=C(-R')-, -C≡C-, -Si(-R')2, -C(=O)-, -NR'-, -O-, -S-, -CONR'- or a divalent aromatic group. In addition, one or more hydrogen atoms in these groups may be substituted with D, F, Cl, Br, I or -CN.

[0018] In the aromatic group, the heteroaromatic group, the aryloxy group, the arylthio group, the aralkyl group, the heteroaralkyl group, the diarylamino group, the arylheteroarylamino group and the diheteroarylamino group, at least one hydrogen atom may be further substituted by R' (excluding hydrogen atoms). R' each independently represents a hydrogen atom, D, F, Cl, Br, I, -N(R'')2, -CN, -NO2, -Si(R'')3, -B(OR'')2, -C(=O)R'', -P(=O)(R'')2, -S(=O)2R'', -OSO2R'', a linear or branched alkyl group having 1 to 30 carbon atoms, a cyclic alkyl group having 3 to 30 carbon atoms, a linear or branched alkoxy group having 1 to 30 carbon atoms, a cyclic alkoxy group having 2 to 30 carbon atoms, a linear or branched alkylthio group having 1 to 30 carbon atoms, a cyclic alkylthio group having 2 to 30 carbon atoms, a linear or branched alkyl group having 2 to 30 carbon atoms, and is selected from a branched alkenyl group, a cyclic alkenyl group having 3 to 30 carbon atoms, a straight-chain or branched alkynyl group having 2 to 30 carbon atoms, a cyclic alkynyl group having 3 to 30 carbon atoms, an aromatic group having 5 to 60 carbon atoms, a heteroaromatic group having 1 to 60 carbon atoms, an aryloxy group having 5 to 40 carbon atoms, an arylthio group having 5 to 40 carbon atoms, an aralkyl group having 5 to 60 carbon atoms, a heteroaralkyl group having 2 to 60 carbon atoms, a diarylamino group having 10 to 40 carbon atoms, an arylheteroarylamino group having 10 to 40 carbon atoms, and a diheteroarylamino group having 10 to 40 carbon atoms.

[0019] In the alkyl group, the alkoxy group, the alkylthio group, the alkenyl group and the alkynyl group, at least one or more hydrogen atoms may be further substituted with R'' (excluding hydrogen atoms), and one -CH2- group or two or more non-adjacent -CH2- groups in these groups may be substituted with -C(-R'')=C(-R'')-, -C≡C, -Si(-R'')2-, -C(=O)-, -NR''-, -O-, -S-, -CONR''- or a divalent aromatic group. In addition, one or more hydrogen atoms in these groups may be substituted with D, F, Cl, Br, I or -CN.

[0020] In the aromatic group, the heteroaromatic group, the aryloxy group, the arylthio group, the aralkyl group, the heteroaralkyl group, the diarylamino group, the arylheteroarylamino group and the diheteroarylamino group, at least one or more hydrogen atoms may be further replaced by R'' (excluding hydrogen atoms). Two or more adjacent R' ’ may be linked together to form an aliphatic or aromatic or heteroaromatic monocyclic or fused ring.

[0021] Each R'' is independently selected from a hydrogen atom, D, F, -CN, an aliphatic hydrocarbon group having from 1 to 20 carbon atoms, an aromatic group having from 5 to 20 carbon atoms, or a heteroaromatic group having from 1 to 20 carbon atoms. Two or more adjacent R″ may be joined together to form an aliphatic or aromatic or heteroaromatic monocyclic or fused ring.

[0022] [3] R in the above formula (2) 31 The iridium complex compound according to the above [1] or [2], [R 31 is selected from a hydrogen atom, D, a linear or branched alkyl group having from 1 to 30 carbon atoms, a cyclic alkyl group having from 3 to 30 carbon atoms, an aralkyl group having from 5 to 60 carbon atoms, or a heteroaralkyl group having from 2 to 60 carbon atoms. In the alkyl group, the aralkyl group, and the heteroaralkyl group, at least one hydrogen atom may be further substituted with R' (excluding hydrogen atoms), and one -CH2- group or two or more non-adjacent -CH2- groups in these groups may be substituted with -C(-R')=C(-R')-, -C≡C-, -Si(-R')2, -C(=O)-, -NR'-, -O-, -S-, -CONR'-, or a divalent aromatic group. In addition, one or more hydrogen atoms in these groups may be substituted with D, F, Cl, Br, I, or -CN. R' has the same meaning as R' in [2] above.]

[0023] [4] R in the above formula (2) 32 The iridium complex compound according to any one of the above [1] to [3], wherein [R 32 is selected from a hydrogen atom, D, a linear or branched alkyl group having from 1 to 30 carbon atoms, a cyclic alkyl group having from 3 to 30 carbon atoms, an aralkyl group having from 5 to 60 carbon atoms, a heteroaralkyl group having from 2 to 60 carbon atoms, an aromatic group having from 5 to 60 carbon atoms, or a heteroaromatic group having from 1 to 60 carbon atoms. In the alkyl group, the aralkyl group, and the heteroaralkyl group, at least one hydrogen atom may be further substituted with R' (excluding hydrogen atoms), and one -CH2- group or two or more non-adjacent -CH2- groups in these groups may be substituted with -C(-R')=C(-R')-, -C≡C-, -Si(-R')2, -C(=O)-, -NR'-, -O-, -S-, -CONR'-, or a divalent aromatic group. In addition, one or more hydrogen atoms in these groups may be substituted with D, F, Cl, Br, I, or -CN. In the aromatic group and the heteroaromatic group, at least one hydrogen atom may be further substituted with R' (excluding hydrogen atoms). R' has the same meaning as R' in [2] above.]

[0024] [5] R in the above formula (1) 21 and R22 The iridium complex compound according to any one of the above [1] to [4], wherein at least one of the above is a linear or branched alkyl group having from 1 to 30 carbon atoms.

[0025] [6] R in the above formula (1) 13 is a substituent represented by the formula (2).

[0026] [7] R in the above formula (1) 6 ~R 9 The iridium complex compound according to any one of the above [1] to [6], wherein at least one of the above has, as a substituent, a linear or branched alkyl group having from 1 to 30 carbon atoms, a cyclic alkyl group having from 3 to 30 carbon atoms, an aromatic group having from 5 to 60 carbon atoms, or an aralkyl group having from 5 to 60 carbon atoms.

[0027] [8] R in the above formula (1) 6 ~R 9 In the iridium complex compound according to any one of the above [1] to [6], adjacent groups among the above are bonded to each other to form a ring.

[0028] In addition, examples of the iridium complex compounds include the following. [9] An iridium complex compound-containing composition comprising the iridium complex compound according to any one of the above [1] to [8] and an organic solvent.

[0029]

[10] The iridium complex compound-containing composition according to [9] above, further comprising a compound represented by the following formula (3) having a maximum emission wavelength shorter than that of the iridium complex compound:

[0030] [ka]

[0031] [In the above formula (3), R 35is an alkyl group having 1 to 20 carbon atoms, a (hetero)aralkyl group having 7 to 40 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a (hetero)aryloxy group having 3 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, an arylsilyl group having 6 to 20 carbon atoms, an alkylcarbonyl group having 2 to 20 carbon atoms, an arylcarbonyl group having 7 to 20 carbon atoms, an alkylamino group having 1 to 20 carbon atoms, an arylamino group having 6 to 20 carbon atoms, or a (hetero)aryl group having 3 to 30 carbon atoms. These groups may further have a substituent. R 35 When multiple are present, they may be the same or different. c is an integer between 0 and 4. Ring A is any one of a pyridine ring, a pyrazine ring, a pyrimidine ring, an imidazole ring, an oxazole ring, a thiazole ring, a quinoline ring, an isoquinoline ring, a quinazoline ring, a quinoxaline ring, an azatriphenylene ring, a carboline ring, a benzothiazole ring, and a benzoxazole ring. Ring A may have a substituent, and the substituent is F, Cl, Br, an alkyl group having 1 to 20 carbon atoms, a (hetero)aralkyl group having 7 to 40 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a (hetero)aryloxy group having 3 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, an arylsilyl group having 6 to 20 carbon atoms, an alkylcarbonyl group having 2 to 20 carbon atoms, an arylcarbonyl group having 7 to 20 carbon atoms, an alkylamino group having 2 to 20 carbon atoms, an arylamino group having 6 to 20 carbon atoms, or a (hetero)aryl group having 3 to 20 carbon atoms. In addition, adjacent substituents bonded to ring A may be bonded to each other to form a further ring. When there are multiple rings A, they may be the same or different. L 2 represents an organic ligand, and n is an integer of 1 to 3.

[0032]

[11] The iridium complex compound-containing composition according to [9] or

[10] above, further comprising a compound represented by the following formula (20):

[0033] [ka]

[0034] [In the above formula (20), Each W independently represents CH or N, and at least one W is N; Xa 1 , Ya 1 , and Za 1 each independently represents a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms which may be substituted, or a divalent aromatic heterocyclic group having 3 to 30 carbon atoms which may be substituted, Xa 2 , Ya 2 and Za 2 each independently represents a hydrogen atom, an aromatic hydrocarbon group having from 6 to 30 carbon atoms which may have a substituent, or an aromatic heterocyclic group having from 3 to 30 carbon atoms which may have a substituent, g11, h11, and j11 each independently represent an integer of 0 to 6; At least one of g11, h11, and j11 is an integer of 1 or more; If g11 is 2 or more, multiple Xa 1 may be the same or different, If h11 is 2 or more, multiple Ya 1 may be the same or different, If j11 is 2 or more, multiple Za 1 may be the same or different, R 23 represents a hydrogen atom or a substituent, and four R 23 may be the same or different, However, if g11, h11, or j11 is 0, the corresponding Xa 2 , Ya 2 , or Za 2 is not a hydrogen atom.)

[0035]

[12] A method for manufacturing an organic electroluminescent device having an anode, a cathode, and at least one organic layer located between the anode and the cathode on a substrate, comprising the steps of: A method for producing an organic electroluminescence device, wherein at least one of the organic layers is formed by a wet film-forming method using the iridium complex compound-containing composition according to any one of [9] to

[11] above.

[0036]

[13] An organic electroluminescent device comprising an anode, a cathode, and at least one organic layer located between the anode and the cathode on a substrate, wherein at least one of the organic layers is a light-emitting layer containing the iridium complex compound according to any one of [1] to [8] above.

[0037]

[14] The organic electroluminescent device according to

[13] above, further comprising a compound represented by the following formula (3) having a maximum emission wavelength shorter than that of the iridium complex compound:

[0038] [ka]

[0039] [In the above formula (3), R 35 is an alkyl group having 1 to 20 carbon atoms, a (hetero)aralkyl group having 7 to 40 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a (hetero)aryloxy group having 3 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, an arylsilyl group having 6 to 20 carbon atoms, an alkylcarbonyl group having 2 to 20 carbon atoms, an arylcarbonyl group having 7 to 20 carbon atoms, an alkylamino group having 1 to 20 carbon atoms, an arylamino group having 6 to 20 carbon atoms, or a (hetero)aryl group having 3 to 30 carbon atoms. These groups may further have a substituent. R 35 When multiple are present, they may be the same or different. c is an integer between 0 and 4. Ring A is any one of a pyridine ring, a pyrazine ring, a pyrimidine ring, an imidazole ring, an oxazole ring, a thiazole ring, a quinoline ring, an isoquinoline ring, a quinazoline ring, a quinoxaline ring, an azatriphenylene ring, a carboline ring, a benzothiazole ring, and a benzoxazole ring. Ring A may have a substituent, and the substituent is F, Cl, Br, an alkyl group having 1 to 20 carbon atoms, a (hetero)aralkyl group having 7 to 40 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a (hetero)aryloxy group having 3 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, an arylsilyl group having 6 to 20 carbon atoms, an alkylcarbonyl group having 2 to 20 carbon atoms, an arylcarbonyl group having 7 to 20 carbon atoms, an alkylamino group having 2 to 20 carbon atoms, an arylamino group having 6 to 20 carbon atoms, or a (hetero)aryl group having 3 to 20 carbon atoms. In addition, adjacent substituents bonded to ring A may be bonded to each other to form a further ring. When there are multiple rings A, they may be the same or different. L 2 represents an organic ligand, and n is an integer of 1 to 3.

[0040]

[15] The organic electroluminescent device according to

[13] or

[14] above, wherein the light-emitting layer further contains a compound represented by the following formula (20):

[0041] [ka]

[0042] [In the above formula (20), Each W independently represents CH or N, and at least one W is N; Xa 1 , Ya 1 , and Za 1 each independently represents a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms which may be substituted, or a divalent aromatic heterocyclic group having 3 to 30 carbon atoms which may be substituted, Xa 2 , Ya 2and Za 2 each independently represents a hydrogen atom, an aromatic hydrocarbon group having from 6 to 30 carbon atoms which may have a substituent, or an aromatic heterocyclic group having from 3 to 30 carbon atoms which may have a substituent, g11, h11, and j11 each independently represent an integer of 0 to 6; At least one of g11, h11, and j11 is an integer of 1 or more; If g11 is 2 or more, multiple Xa 1 may be the same or different, If h11 is 2 or more, multiple Ya 1 may be the same or different, If j11 is 2 or more, multiple Za 1 may be the same or different, R 23 represents a hydrogen atom or a substituent, and four R 23 may be the same or different, However, if g11, h11, or j11 is 0, the corresponding Xa 2 , Ya 2 , or Za 2 is not a hydrogen atom.)

[0043]

[16] An organic EL display device comprising the organic electroluminescent device according to any one of

[13] to

[15] above.

[0044]

[17] An organic EL lighting device comprising the organic electroluminescent element according to any one of

[13] to

[15] above. Effect of the Invention

[0045] According to the above-mentioned composition, it is possible to provide an iridium complex compound which has a narrow half-width, high solubility in a solvent, and a luminous efficiency equal to or higher than that of conventional compounds. [Brief description of the drawings]

[0046] [Figure 1] FIG. 1 is a cross-sectional view that illustrates a schematic example of the structure of an organic electroluminescent device of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0047] The following describes in detail the embodiments of the present invention, but the present invention is not limited to the following embodiments and can be modified in various ways within the scope of the invention. In this specification, the term "aromatic ring" refers to an "aromatic hydrocarbon ring" and is distinguished from a "heteroaromatic ring" that contains a heteroatom as a ring-constituting atom. Similarly, the term "aromatic group" refers to an "aromatic hydrocarbon group" or an "aromatic hydrocarbon ring group", and the term "heteroaromatic group" refers to a "heteroaromatic ring group". Additionally, "D" refers to deuterium. Among the substituents, the (hetero)aralkyl group refers to an aralkyl group which may be substituted with a heteroatom, the (hetero)aryloxy group refers to an aryloxy group which may be substituted with a heteroatom, and the (hetero)aryl group refers to an aryl group which may be substituted with a heteroatom. In the structural formula, Me represents a methyl group, Et represents an ethyl group, and Bu represents an t “Ph” refers to a tertiary butyl group, “Tf” refers to a trifluoromethylsulfonyl group, and “Ac” refers to an acetyl group.

[0048] As a result of intensive investigations conducted by the inventors to solve the above-mentioned problems, they discovered that an iridium complex compound having a specific chemical structure exhibits an extremely narrow half-width as a red emitting material compared to conventional materials, while at the same time exhibiting high solubility and PL quantum yield, and thus completed the present invention.

[0049] [Iridium complex compounds] The iridium complex compound according to this embodiment is a compound represented by formula (1).

[0050] [ka]

[0051] [In formula (1), Ir represents an iridium atom.5 ~R 14 , R 21 and R 22 each independently represents a hydrogen atom, D, F, Cl, Br, I, or a substituent. Adjacent groups may be further bonded to form a ring. However, R 12 and R 13 Any one of the above is a substituent represented by the following formula (2).

[0052] [ka]

[0053] [In formula (2), the dashed line represents a bond to formula (1). R 31 represents a hydrogen atom, D, an alkyl group, an aralkyl group, or a heteroaralkyl group; R 32 R represents a hydrogen atom, D, an alkyl group, an aralkyl group, a heteroaralkyl group, an aromatic group, or a heteroaromatic group. 31 and R 32 may be further substituted.

[0054] The iridium complex compound according to this embodiment exhibits an extremely narrow half-width as a red light emitting material compared to conventional materials, and at the same time, exhibits high solubility and solution PL quantum yield. The reason for this is presumed to be as follows.

[0055] Patent Document 1 discloses an iridium complex having a structure in which a triazine ring is bonded to a fluorene-pyridine ligand, and two aromatic rings are further bonded to the triazine ring. It is believed that the fact that two aromatic rings are bonded to the triazine causes rotational motion between these rings and the LUMO extends to the aromatic ring site, which tends to widen the half-width. On the other hand, in the case of the iridium complex compound of formula (1), when an aromatic ring is bonded to the triazine, R 32 It is believed that the half-width could be narrowed because it is limited to

[0056] The LUMO is located on the triazine ring, and when an aromatic ring is bonded to the triazine ring so that the π-electron system is conjugated, the LUMO spreads onto the aromatic ring, and the rotational motion of the bond between the triazine ring and the aromatic ring has a significant effect on the shape of the spectrum, widening the half-width. This effect is remarkable when two aromatic rings are substituted on the triazine ring. On the other hand, by substituting one or more alkyl groups or (hetero)aralkyl groups, which do not spread the π-electron conjugated system, on the triazine ring, the effect of effectively shielding the interaction with the external environment, i.e., the solvent molecules in a solution state, or the host molecules in the light-emitting layer of an organic EL device, is created in the vicinity of the triazine ring, thereby narrowing the half-width further.

[0057] The ligand structure of the complex in this embodiment is such that a triazine ring is substituted at a specific site of the fluorene-pyridine main skeleton as shown in formula (2). The LUMO is considered to be localized on the triazine ring, and the decrease in MLCT properties due to the decrease in the participation of iridium atoms is compensated for by the fact that the fluorene-pyridine has a linear structure and the overlap between the HOMO and LUMO on the ligand is quite large, so the quantum yield does not decrease.

[0058] When the involvement of iridium atoms decreases, the contribution of LC (Ligand Centered) emission increases, so the spectrum does not become broader, and a main peak with a relatively narrow half-width is observed strongly, although it is accompanied by a vibration structure. (Reference: Yoichi Sasaki and Osamu Ishitani, eds., Coordination Chemistry Society Selection 2, Photochemistry of Metal Complexes, pp. 83-98, Sankyo Publishing Co., Ltd., 2007) It is not easy to synthesize a so-called heteroleptic iridium complex having asymmetric ligands as disclosed in Patent Document 2. In addition, since the ligands are asymmetric, they have many vibrational modes compared to the highly symmetric homoleptic type, and further, the distribution of HOMO and LUMO also has a widening between different ligands, or the sub-ligands interfere with the main ligand involved in the emission, resulting in a widening of the half-width.

[0059] On the other hand, the iridium complex compound represented by formula (1) according to this embodiment can narrow the half-width by forming a homoleptic complex (L3Ir) in which all three ligands to trivalent iridium are the same. Also, a heteroleptic complex (L 1 2L 2 Ir, L 1 L 2 2Ir or L 1 L 2 L 3 Unlike the case of Ir), different ligands do not affect each other, so the quantum yield also tends to be improved in this respect.

[0060] <R 5 ~R 14 , R 21 and R 22 > R in formula (1) 5 ~R 14 represents a hydrogen atom, D, F, Cl, Br, I or a substituent. R 5 ~R 14 , R 21 and R 22 are each independent and may be the same or different. R 5 ~R 14 , R 21 and R 22 When is a substituent, the type is not particularly limited, and an optimal substituent can be selected in consideration of precise control of the desired emission wavelength, compatibility with the solvent used, compatibility with the host compound when made into an organic electroluminescent device, etc. In considering such optimization, the preferred substituents are within the ranges described below.

[0061] R 5 ~R 14 , R 21 and R 22each independently represents a hydrogen atom, D, F, Cl, Br, I, -N(R')2, -CN, -NO2, -OH, -COOR', -C(=O)R', -C(=O)NR', ​​-P(=O)(R')2, -S(=O)R', -S(=O)2R', -OS(=O)2R', a linear or branched alkyl group having from 1 to 30 carbon atoms, a cyclic alkyl group having from 3 to 30 carbon atoms, a linear or branched alkoxy group having from 1 to 30 carbon atoms, a cyclic alkoxy group having from 2 to 30 carbon atoms, a linear or branched alkylthio group having from 1 to 30 carbon atoms, a cyclic alkylthio group having from 2 to 30 carbon atoms, a linear or branched alkyl group having from 2 to 30 carbon atoms, or a branched alkenyl group, a cyclic alkenyl group having 3 to 30 carbon atoms, a linear or branched alkynyl group having 2 to 30 carbon atoms, a cyclic alkynyl group having 3 to 30 carbon atoms, an aromatic group having 5 to 60 carbon atoms, a heteroaromatic group having 1 to 60 carbon atoms, an aryloxy group having 5 to 40 carbon atoms, an arylthio group having 5 to 40 carbon atoms, an aralkyl group having 5 to 60 carbon atoms, a heteroaralkyl group having 2 to 60 carbon atoms, a diarylamino group having 10 to 40 carbon atoms, an arylheteroarylamino group having 10 to 40 carbon atoms, or a diheteroarylamino group having 10 to 40 carbon atoms.

[0062] In the alkyl group, the alkoxy group, the alkylthio group, the alkenyl group and the alkynyl group, at least one hydrogen atom may be further replaced by R' (excluding hydrogen atoms). In these groups, i.e., the alkyl group, the alkoxy group, the alkylthio group, the alkenyl group and the alkynyl group, and R' (excluding hydrogen atoms), one -CH2- group or two or more non-adjacent -CH2- groups may be replaced by -C(-R')=C(-R')-, -C≡C-, -Si(-R')2, -C(=O)-, -NR'-, -O-, -S-, -CONR'- or a divalent aromatic group. In addition, in these groups, one or more hydrogen atoms may be replaced by D, F, Cl, Br, I or -CN.

[0063] In the aromatic group, the heteroaromatic group, the aryloxy group, the arylthio group, the aralkyl group, the heteroaralkyl group, the diarylamino group, the arylheteroarylamino group and the diheteroarylamino group, at least one hydrogen atom may be further substituted with R' (excluding hydrogen atoms) each independently. R' will be described later.

[0064] Examples of linear or branched alkyl groups having 1 to 30 carbon atoms, or cyclic alkyl groups having 3 to 30 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, n-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, isopropyl, isobutyl, tert-butyl, cyclopentyl, cyclohexyl, n-octyl, norbornyl, and adamantyl. In the case of an alkyl group, if the number of carbon atoms is too large, the complex is highly shielded and durability is impaired, so the number of carbon atoms is preferably 1 or more, and is preferably 30 or less, more preferably 20 or less, and even more preferably 12 or less. However, in the case of a branched alkyl group, the shielding effect is greater than that of a linear alkyl group or a cyclic alkyl group, so the number of carbon atoms is most preferably 7 or less. In the case of a cyclic alkyl group, the number of carbon atoms is 3 or more.

[0065] Examples of linear or branched alkoxy groups having 1 to 30 carbon atoms, or cyclic alkoxy groups having 2 to 30 carbon atoms include methoxy, ethoxy, n-propyloxy, n-butoxy, n-hexyloxy, isopropyloxy, cyclohexyloxy, 2-ethoxyethoxy, and 2-ethoxyethoxyethoxy. From the viewpoint of durability, the number of carbon atoms is preferably 1 or more, and is preferably 30 or less, more preferably 20 or less, and most preferably 12 or less. In the case of a cyclic alkoxy group, the number of carbon atoms is 2 or more.

[0066] Examples of linear or branched alkylthio groups having 1 to 30 carbon atoms, or cyclic alkylthio groups having 2 to 30 carbon atoms include methylthio, ethylthio, n-propylthio, n-butylthio, n-hexylthio, isopropylthio, cyclohexylthio, 2-methylbutylthio, and n-hexylthio. From the viewpoint of durability, the number of carbon atoms is preferably 1 or more, and is preferably 30 or less, more preferably 20 or less, and most preferably 12 or less. In the case of a cyclic alkylthio group, the number of carbon atoms is 2 or more.

[0067] Examples of linear or branched alkenyl groups having 2 to 30 carbon atoms, or cyclic alkenyl groups having 3 to 30 carbon atoms include vinyl groups, allyl groups, propenyl groups, heptenyl groups, cyclopentenyl groups, cyclohexenyl groups, and cyclooctenyl groups. From the viewpoint of durability, the number of carbon atoms is preferably 2 or more, and preferably 30 or less, more preferably 20 or less, and most preferably 12 or less. In the case of cyclic alkenyl groups, the number of carbon atoms is 3 or more.

[0068] Examples of linear or branched alkynyl groups having 2 to 30 carbon atoms, or cyclic alkynyl groups having 3 to 30 carbon atoms include ethynyl, propionyl, butynyl, pentynyl, hexynyl, heptynyl, and octynyl. From the viewpoint of durability, the number of carbon atoms is preferably 2 or more, and preferably 30 or less, more preferably 20 or less, and most preferably 12 or less. In the case of a cyclic alkynyl group, the number of carbon atoms is 3 or more.

[0069] The aromatic group having 5 to 60 carbon atoms and the heteroaromatic group having 1 to 60 carbon atoms may exist as a single ring or a condensed ring, or may be a group formed by bonding or condensing another type of aromatic group or heteroaromatic group to a single ring. Examples of these include a phenyl group, a naphthyl group, anthracenyl group, a benzoanthracenyl group, a phenanthrenyl group, a benzophenanthrenyl group, a pyrenyl group, a chrysenyl group, a fluoranthenyl group, a perylenyl group, a benzopyrenyl group, a benzofluoranthenyl group, a naphthacenyl group, a pentacenyl group, a biphenyl group, a terphenyl group, a fluorenyl group, a spirobifluorenyl group, a dihydrophenanthrenyl group, a dihydropyrenyl group, a tetrahydropyrenyl group, an indenofluorenyl group, a furyl group, a benzofuryl group, an isobenzofuryl group, a dibenzofuranyl group, a thiophene group, a benzothiophenyl group, a dibenzothiophenyl group, a pyrrolyl group, an indolyl group, an isoindolyl group, a carbazolyl group, a benzocarbazolyl group, an indolocarbazolyl group, an indenocarbazolyl group, a pyridyl group, a cinnolyl group, an isocinnolyl group, an acridyl group, and a phenanthridyl group. , Pi Examples of such groups include azolyl group, indazolyl group, imidazolyl group, benzimidazolyl group, naphthimidazolyl group, phenanthroimidazolyl group, pyridineimidazolyl group, oxazolyl group, benzoxazolyl group, naphthoxazolyl group, thiazolyl group, benzothiazolyl group, pyrimidyl group, benzopyrimidyl group, pyridazinyl group, quinoxalinyl group, diazaanthracenyl group, diazapyrenyl group, pyrazinyl group, phenoxazinyl group, phenothiazinyl group, naphthyridinyl group, azacarbazolyl group, benzocarbolinyl group, phenanthrolyl group, triazolyl group, benzotriazolyl group, oxadiazolyl group, thiadiazolyl group, triazinyl group, 2,6-diphenyl-1,3,5-triazin-4-yl group, tetrazolyl group, purinyl group, and benzothiadiazolyl group.

[0070] From the viewpoint of the balance between solubility and durability, the number of carbon atoms in these groups is preferably 3 or more, more preferably 5 or more, and is preferably 50 or less, more preferably 40 or less, and most preferably 30 or less.

[0071] Examples of the aryloxy group having 5 to 40 carbon atoms include a phenoxy group, a methylphenoxy group, a naphthoxy group, a methoxyphenoxy group, etc. From the viewpoint of the balance between solubility and durability, the number of carbon atoms in these aryloxy groups is preferably 5 or more and is preferably 30 or less, more preferably 25 or less, and most preferably 20 or less.

[0072] Examples of the arylthio group having 5 to 40 carbon atoms include a phenylthio group, a methylphenylthio group, a naphthylthio group, a methoxyphenylthio group, etc. From the viewpoint of the balance between solubility and durability, the number of carbon atoms in these arylthio groups is preferably 5 or more and is preferably 30 or less, more preferably 25 or less, and most preferably 20 or less.

[0073] Examples of aralkyl groups having 5 to 60 carbon atoms include 1,1-dimethyl-1-phenylmethyl group, 1,1-di(n-butyl)-1-phenylmethyl group, 1,1-di(n-hexyl)-1-phenylmethyl group, 1,1-di(n-octyl)-1-phenylmethyl group, phenylmethyl group, phenylethyl group, 3-phenyl-1-propyl group, 4-phenyl-1-n-butyl group, 1-methyl-1-phenylethyl group, 5-phenyl-1-n-propyl group, 6-phenyl-1-n-hexyl group, 6-naphthyl-1-n-hexyl group, 7-phenyl-1-n-heptyl group, 8-phenyl-1-n-octyl group, and 4-phenylcyclohexyl group. From the viewpoint of the balance between solubility and durability, the number of carbon atoms of these aralkyl groups is preferably 5 or more, and more preferably 40 or less.

[0074] Examples of heteroaralkyl groups having 2 to 60 carbon atoms include 1,1-dimethyl-1-(2-pyridyl)methyl group, 1,1-di(n-hexyl)-1-(2-pyridyl)methyl group, (2-pyridyl)methyl group, (2-pyridyl)ethyl group, 3-(2-pyridyl)-1-propyl group, 4-(2-pyridyl)-1-n-butyl group, 1-methyl-1-(2-pyridyl)ethyl group, 5-(2 Examples of the heteroaralkyl groups include 6-(2-pyridyl)-1-n-propyl group, 6-(2-pyridyl)-1-n-hexyl group, 6-(2-pyrimidyl)-1-n-hexyl group, 6-(2,6-diphenyl-1,3,5-triazin-4-yl)-1-n-hexyl group, 7-(2-pyridyl)-1-n-heptyl group, 8-(2-pyridyl)-1-n-octyl group, and 4-(2-pyridyl)cyclohexyl group. From the viewpoint of the balance between solubility and durability, the number of carbon atoms in these heteroaralkyl groups is preferably 5 or more, and is preferably 50 or less, more preferably 40 or less, and most preferably 30 or less.

[0075] Examples of diarylamino groups having 10 to 40 carbon atoms include a diphenylamino group, a phenyl(naphthyl)amino group, a di(biphenyl)amino group, a di(p-terphenyl)amino group, etc. From the viewpoint of the balance between solubility and durability, the number of carbon atoms in these diarylamino groups is preferably 10 or more and is preferably 36 or less, more preferably 30 or less, and most preferably 25 or less.

[0076] Examples of the arylheteroarylamino group having 10 to 40 carbon atoms include a phenyl(2-pyridyl)amino group, a phenyl(2,6-diphenyl-1,3,5-triazin-4-yl)amino group, etc. From the viewpoint of the balance between solubility and durability, the number of carbon atoms in these arylheteroarylamino groups is preferably 10 or more, and is preferably 36 or less, more preferably 30 or less, and most preferably 25 or less.

[0077] Examples of the diheteroarylamino group having 10 to 40 carbon atoms include a di(2-pyridyl)amino group, a di(2,6-diphenyl-1,3,5-triazin-4-yl)amino group, etc. From the viewpoint of the balance between solubility and durability, the number of carbon atoms in these diheteroarylamino groups is preferably 10 or more, and is preferably 36 or less, more preferably 30 or less, and most preferably 25 or less.

[0078] R 5 ~R 14 In particular, from the viewpoint of not impairing the durability as a light-emitting material in an organic electroluminescent device, each of them is preferably a hydrogen atom, F, -CN, a linear or branched alkyl group having from 1 to 30 carbon atoms, a cyclic alkyl group having from 3 to 30 carbon atoms, an aryloxy group having from 5 to 40 carbon atoms, an arylthio group having from 5 to 40 carbon atoms, a diarylamino group having from 10 to 40 carbon atoms, an aralkyl group having from 5 to 60 carbon atoms, an aromatic group having from 5 to 60 carbon atoms, or a heteroaromatic group having from 1 to 60 carbon atoms, more preferably a hydrogen atom, F, -CN, an alkyl group, an aralkyl group, an aromatic group, or a heteroaromatic group, and most preferably a hydrogen atom, F, -CN, an alkyl group, an aromatic group, or a heteroaromatic group.

[0079] R 21 and R 22 Regarding R 5 ~R 14 For the same reasons as above, each of the above is preferably a hydrogen atom, F, -CN, a linear or branched alkyl group having 1 to 30 carbon atoms, a cyclic alkyl group having 3 to 30 carbon atoms, an aryloxy group having 5 to 40 carbon atoms, an arylthio group having 5 to 40 carbon atoms, a diarylamino group having 10 to 40 carbon atoms, an aralkyl group having 5 to 60 carbon atoms, an aromatic group having 5 to 60 carbon atoms, or a heteroaromatic group having 1 to 60 carbon atoms, and more preferably F, -CN, an alkyl group, an aralkyl group, an aromatic group, or a heteroaromatic group. Particularly preferred is a linear or branched alkyl group having 1 to 30 carbon atoms, and R 21 and R 22It is most preferable that at least one of the above is a linear or branched alkyl group having 1 to 30 carbon atoms. This is because it provides appropriate solubility when used as an emitting layer of an organic EL device, and further, by appropriately shielding the fluorene moiety in which the HOMO is distributed, it is possible to suppress the process of quenching due to interaction with adjacent host molecules in the layer.

[0080] From the viewpoint of improving life span, R 6 ~R 9 or R 6 ~R 9 It is preferred that adjacent groups of the formula (I) are bonded to each other to form a ring.

[0081] R 6 ~R 9 is the above-mentioned substituent, or R 6 ~R 9 By further bonding adjacent groups to each other to form a ring, the probability that the fluorene will capture holes can be increased. In the iridium complex compound of formula (1), when an aromatic ring is bonded to the triazine, R 32 Therefore, the half-width can be narrowed, but the range of conjugation is narrowed, which may reduce the electron resistance of triazine and shorten the lifetime. capture It is believed that an increased probability of recombination increases the proportion of triazine electrons consumed for recombination with holes, thereby suppressing or improving the decrease in lifetime.

[0082] From the viewpoint of improving luminous efficiency, R 6 ~R 9 It is preferable that any one of the above is a substituent selected from a linear or branched alkyl group having 1 to 30 carbon atoms, a cyclic alkyl group having 3 to 30 carbon atoms, an aromatic group having 5 to 60 carbon atoms, and an aralkyl group having 5 to 60 carbon atoms. Specific examples of these are the above-mentioned R 5 ~R 14 The substituents may further include the above-mentioned R' as a substituent.

[0083] Particularly preferred examples of the linear or branched alkyl group having 1 to 30 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an isopropyl group, an isobutyl group, and a tert-butyl group. Particularly preferred aromatic groups having 5 to 60 carbon atoms are phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, phenanthrenyl, fluorenyl, dibenzofuranyl, dibenzothiophenyl, and carbazole groups, and more preferred are phenyl, biphenyl, and naphthyl groups. Particularly preferred aralkyl groups having 5 to 60 carbon atoms include a 1,1-dimethyl-1-phenylmethyl group, a 1,1-di(n-butyl)-1-phenylmethyl group, a 1,1-di(n-hexyl)-1-phenylmethyl group, a 3-phenyl-1-propyl group, a 4-phenyl-1-n-butyl group, a 5-phenyl-1-n-propyl group, and a 6-phenyl-1-n-hexyl group.

[0084] The aromatic group having 5 to 60 carbon atoms preferably further has an aralkyl group having 5 to 60 carbon atoms as the substituent R'. Specific examples thereof include a 1,1-dimethyl-1-phenylmethylphenyl group, a 1,1-di(n-butyl)-1-phenylmethylphenyl group, a 1,1-di(n-hexyl)-1-phenylmethylphenyl group, a 3-phenyl-1-propylphenyl group, a 4-phenyl-1-n-butylphenyl group, a 5-phenyl-1-n-propylphenyl group, and a 6-phenyl-1-n-hexylphenyl group. From the viewpoint of improving the life span and the luminous efficiency, R 6 ~R 9 Of these, R 8 is a substituent, most preferably R 6 , R 7 and R 9 is hydrogen and R 8 is the only substituent.

[0085] R 6 ~R9 Preferred examples of the ring formed by bonding adjacent groups of R 6 and R 7 R is a ring-forming 7H-benzo[c]fluorene or 2,3,4,7-tetrahydro-1H-benzo[c]fluorene; 7 and R 8 R is a ring-forming 11H-benzo[b]fluorene or 7,8,9,11-tetrahydro-6H-benzo[b]fluorene; 8 and R 9 is a ring-forming 11H-benzo[a]fluorene or 2,3,4,11-tetrahydro-1H-benzo[a]fluorene. Among these, 7H-benzo[c]fluorene is particularly preferred.

[0086] <R’> In this specification, R' is a hydrogen atom, D, F, Cl, Br, I, -N(R'')2, -CN, -NO2, -Si(R'')3, -B(OR'')2, -C(=O)R'', -P(=O)(R'')2, -S(=O)2R'', -OSO2R'', a linear or branched alkyl group having 1 to 30 carbon atoms, a cyclic alkyl group having 3 to 30 carbon atoms, a linear or branched alkoxy group having 1 to 30 carbon atoms, a cyclic alkoxy group having 2 to 30 carbon atoms, a linear or branched alkylthio group having 1 to 30 carbon atoms, a cyclic alkylthio group having 2 to 30 carbon atoms, a linear or branched alkyl group having 2 to 30 carbon atoms, a cyclic alkylthio group having 2 to 30 carbon atoms, a linear or branched alkyl group having 2 to 30 carbon atoms, a cyclic alkylthio group having 2 to 30 carbon atoms, a linear or It is selected from a branched alkenyl group, a cyclic alkenyl group having from 3 to 30 carbon atoms, a linear or branched alkynyl group having from 2 to 30 carbon atoms, a cyclic alkynyl group having from 3 to 30 carbon atoms, an aromatic group having from 5 to 60 carbon atoms, a heteroaromatic group having from 1 to 60 carbon atoms, an aryloxy group having from 5 to 40 carbon atoms, an arylthio group having from 5 to 40 carbon atoms, an aralkyl group having from 5 to 60 carbon atoms, a heteroaralkyl group having from 2 to 60 carbon atoms, a diarylamino group having from 10 to 40 carbon atoms, an arylheteroarylamino group having from 10 to 40 carbon atoms, or a diheteroarylamino group having from 10 to 40 carbon atoms. When there are multiple R', they may be the same or different.

[0087] In the alkyl group, the alkoxy group, the alkylthio group, the alkenyl group and the alkynyl group, at least one or more hydrogen atoms may be further substituted with R'' (excluding hydrogen atoms). In these groups, i.e., the alkyl group, the alkoxy group, the alkylthio group, the alkenyl group and the alkynyl group, one -CH2- group or two or more non-adjacent -CH2- groups may be substituted with -C(-R'')=C(-R'')-, -C≡C, -Si(-R'')2-, -C(=O)-, -NR''-, -O-, -S-, -CONR''- or a divalent aromatic group. In addition, in these groups, one or more hydrogen atoms may be substituted with D, F, Cl, Br, I or -CN.

[0088] Furthermore, the aromatic group, the heteroaromatic group, the aryloxy group, the arylthio group, the aralkyl group, the heteroaralkyl group, the diarylamino group, the arylheteroarylamino group and the diheteroarylamino group may each independently have at least one hydrogen atom further substituted with R″ (excluding hydrogen atoms). R″ will be described later. Additionally, two or more adjacent R' may be joined together to form an aliphatic or aromatic or heteroaromatic monocyclic or fused ring. All of the above-mentioned examples of groups are R 5 ~R 14 This is the same as described in the previous section.

[0089] <R’’> R'' is selected from a hydrogen atom, D, F, -CN, an aliphatic hydrocarbon group having from 1 to 20 carbon atoms, an aromatic group having from 5 to 20 carbon atoms, or a heteroaromatic group having from 1 to 20 carbon atoms. Two or more adjacent R" may be bonded together to form an aliphatic or aromatic or heteroaromatic monocyclic or fused ring. When there are multiple R", they may be the same or different.

[0090] <Formula (2)> R in Equation (1) 12 and R 13is a substituent represented by formula (2). The site where formula (2) is provided is R 12 or R 13 However, from the viewpoint of durability and narrowing the half-value width, R 13 It is.

[0091] <R 31 and R 32 > R 31 is a hydrogen atom, D, or a substituent, and the substituent is selected from a linear or branched alkyl group having from 1 to 30 carbon atoms, a cyclic alkyl group having from 3 to 30 carbon atoms, an aralkyl group having from 5 to 60 carbon atoms, or a heteroaralkyl group having from 2 to 60 carbon atoms. In the alkyl group, the aralkyl group, and the heteroaralkyl group, at least one hydrogen atom may be further substituted with R' (excluding hydrogen atoms). In these groups, i.e., the alkyl group, the aralkyl group, the heteroaralkyl group, and R' (excluding hydrogen atoms), one -CH2- group or two or more non-adjacent -CH2- groups may be replaced with -C(-R')=C(-R')-, -C≡C-, -Si(-R')2, -C(=O)-, -NR'-, -O-, -S-, -CONR'-, or a divalent aromatic group. In addition, in these groups, one or more hydrogen atoms may be replaced with D, F, Cl, Br, I, or -CN.

[0092] The preferred structures of these substituents are 5 ~R 14 R′ is the same as above. From the viewpoint of solubility and durability, alkyl groups are more preferred, and linear or branched alkyl groups having 7 or less carbon atoms are particularly preferred, such as t-butyl groups.

[0093] R 32represents a hydrogen atom, D, or a substituent, and the substituent is selected from a linear or branched alkyl group having from 1 to 30 carbon atoms, a cyclic alkyl group having from 3 to 30 carbon atoms, an aralkyl group having from 5 to 60 carbon atoms, a heteroaralkyl group having from 2 to 60 carbon atoms, an aromatic group having from 5 to 60 carbon atoms, or a heteroaromatic group having from 1 to 60 carbon atoms.

[0094] In the alkyl group, the aralkyl group, and the heteroaralkyl group, at least one hydrogen atom may be further substituted with R' (excluding hydrogen atoms). In these groups, i.e., the alkyl group, the aralkyl group, the heteroaralkyl group, and R' (excluding hydrogen atoms), one -CH2- group or two or more non-adjacent -CH2- groups may be replaced with -C(-R')=C(-R')-, -C≡C-, -Si(-R')2, -C(=O)-, -NR'-, -O-, -S-, -CONR'-, or a divalent aromatic group. In addition, in these groups, one or more hydrogen atoms may be replaced with D, F, Cl, Br, I, or -CN.

[0095] In the aromatic group and the heteroaromatic group, at least one hydrogen atom may be further substituted with R' (excluding hydrogen atoms). The preferred structures of these substituents are 5 ~R 14 and R' is the same as above. More preferably, from the viewpoint of solubility and durability, it is an aromatic group or an alkyl group which may have a substituent. Particularly preferably, it is a linear or branched alkyl group having 7 or less carbon atoms, an aromatic group having 6 to 30 carbon atoms, an aromatic group having 6 to 30 carbon atoms and having a linear or branched alkyl group having 7 or less carbon atoms, or an aromatic group having 6 to 30 carbon atoms and having an aralkyl group having 7 or more and 30 or less carbon atoms.

[0096] A specific example of a linear or branched alkyl group having 7 or less carbon atoms is a t-butyl group. The aromatic group having 6 to 30 carbon atoms is preferably an aromatic hydrocarbon group, specifically, for example, a phenyl group, a naphthyl group, or a biphenyl group, and the aromatic hydrocarbon group preferably further has a substituent or is a condensed ring. The aromatic hydrocarbon having a substituent is preferably an aromatic group having 6 to 30 carbon atoms and having a linear or branched alkyl group having 7 or less carbon atoms, or an aromatic group having 6 to 30 carbon atoms and having an aralkyl group having 7 or more and 30 or less carbon atoms, and the condensed ring is preferably a naphthyl group. A specific example of the aromatic group having 6 to 30 carbon atoms and having a linear or branched alkyl group having 7 or less carbon atoms is a 4-t-butylphenyl group. Specific examples of aromatic groups having 6 to 30 carbon atoms and having an aralkyl group having 7 or more and 30 or less carbon atoms include a 1,1-dimethyl-1-phenylmethylphenyl group, a 1,1-di(n-butyl)-1-phenylmethylphenyl group, a 1,1-di(n-hexyl)-1-phenylmethylphenyl group, a 3-phenyl-1-propylphenyl group, a 4-phenyl-1-n-butylphenyl group, a 5-phenyl-1-n-propylphenyl group, and a 6-phenyl-1-n-hexylphenyl group.

[0097] From the viewpoint of half-width, R 31 and R 32 On the other hand, when the alkyl group is a branched alkyl group, the electron access to the triazine may be hindered. From the viewpoint of durability, R 32 is preferably an aromatic group, and particularly preferably an aromatic group having 6 to 30 carbon atoms and having a linear or branched alkyl group having 7 or less carbon atoms, or an aromatic group having 6 to 30 carbon atoms and having an aralkyl group having 7 or more and 30 or less carbon atoms.

[0098] <Example> Preferred specific examples of the iridium complex compound according to this embodiment other than those shown in the examples given later will be shown below, but the present invention is not limited to these.

[0099] [ka]

[0100] [ka]

[0101] Specific examples of more preferred embodiments are given below.

[0102] [ka]

[0103] [ka]

[0104] <Maximum emission wavelength> The iridium complex compound according to this embodiment can make the emission wavelength longer. As an index showing the length of the emission wavelength, the maximum emission wavelength measured by the procedure shown below is preferably 600 nm or more, more preferably 610 nm or more, and even more preferably 615 nm or more. In addition, the maximum emission wavelength is preferably 650 nm or less, more preferably 640 nm or less, and even more preferably 635 nm or less. By being within these ranges, it tends to be possible to express the preferred color of the red light-emitting material suitable for an organic electroluminescent device.

[0105] (Method for measuring maximum emission wavelength) At room temperature, the iridium complex compound is dissolved in a solvent such as toluene or 2-methyltetrahydrofuran at a concentration of 1×10 -4 The phosphorescence spectrum of the solution dissolved at mol / L or less is measured using a spectrophotometer (Organic EL Quantum Yield Measurement System C9920-02 manufactured by Hamamatsu Photonics KK). The wavelength showing the maximum intensity of the obtained phosphorescence spectrum is regarded as the maximum emission wavelength in this embodiment.

[0106] <Method for synthesizing iridium complex compounds> <Synthesis method of ligand> The ligand of the iridium complex compound according to this embodiment can be synthesized by combining known methods. The fluorene ring can be easily introduced, for example, by using a compound having bromine, -B(OH)2 group, acetyl group, or carboxy group at the 2-position of the fluorene ring as a raw material. The fluorene-pyridine ligand can be synthesized by further synthesizing these raw materials by Suzuki-Miyaura coupling reaction with halogenated pyridines. If the halogenated pyridine used is, for example, 5-bromo-2-iodopyridine, the intermediate obtained is fluorene-pyridine in which bromine is substituted on the pyridine, and this can be further led to a boronic acid ester, and the final ligand can be synthesized by the Suzuki-Miyaura coupling reaction with the next disubstituted chlorotriazine compound.

[0107] There are various known methods for synthesizing disubstituted chlorotriazine compounds. When introducing two identical substituents into a triazine ring, the compound can be synthesized by reacting two equivalents of a Grignard reagent with cyanuric chloride, as described in, for example, JP 2016-160180 A. In addition, when introducing an asymmetric substituent into a triazine ring, a method of introducing the substituent stepwise using Grignard reaction and Suzuki-Miyaura coupling reaction is preferable, for example, the method described in Chinese Patent Publication No. 101544613.

[0108] [ka]

[0109] <Method for synthesizing iridium complex compounds > The iridium complex compound according to this embodiment can be synthesized by combining known methods, which will be described in detail below. Regarding the synthesis method of iridium complex compounds, a method via a chlorine-bridged iridium dinuclear complex as shown in the following formula [A] using a phenylpyridine ligand as an example for ease of understanding (MG Colombo, T. C. Brunold, T. Riedener, HU Gudel, , Inorg. Chem., 1994, 33, 545-550), and a method in which a binuclear complex as shown in the following formula [B] is converted into a mononuclear complex by further exchanging the chlorine bridge with acetylacetonate to obtain the target compound (S. Lamansky, P. Djurovich, D. Murphy, F. Abdel-Razzaq, R. Kwong, I. Tsyba, M. Borz, B. Mui, R. Bau, M. Thompson, Inorg. Chem., 2001, 40, 1704-1711), but are not limited thereto.

[0110] For example, typical reaction conditions represented by the following formula [A] are as follows. In the first step, a chlorine-bridged iridium dinuclear complex is synthesized by reacting two equivalents of the ligand with one equivalent of iridium chloride n-hydrate. The solvent is usually a mixture of 2-ethoxyethanol and water, but no solvent or other solvents may be used. The reaction can be accelerated by using an excess of the ligand or by using an additive such as a base. Other bridging anionic ligands such as bromine can also be used instead of chlorine.

[0111] There is no particular restriction on the reaction temperature, but it is usually preferably 0° C. or higher, more preferably 50° C. or higher. The reaction temperature is preferably 250° C. or lower, more preferably 150° C. or lower. Within these ranges, only the target reaction proceeds without the generation of by-products or decomposition reactions, and high selectivity tends to be obtained.

[0112] [ka]

[0113] In the second step, a halide ion trapping agent such as silver trifluoromethanesulfonate is added and brought into contact with the newly added ligand to obtain the desired complex. The solvent is usually ethoxyethanol or diglyme, but depending on the type of ligand, no solvent or other solvents can be used, and multiple solvents can also be mixed and used. The addition of a halide ion trapping agent is not necessarily required because the reaction may proceed without it, but it is advantageous to add the trapping agent to increase the reaction yield and selectively synthesize a facial isomer with a higher quantum yield. There is no particular limit to the reaction temperature, but the reaction is usually carried out in the range of 0°C to 250°C.

[0114] In addition, typical reaction conditions represented by the following formula [B] will be described. The binuclear complex in the first step can be synthesized in the same manner as in formula [A] above. In the second step, the binuclear complex is converted into a mononuclear complex coordinated with a 1,3-diketonato ligand by reacting it with one equivalent or more of a 1,3-dicarbonyl compound such as acetylacetone and one equivalent or more of a basic compound capable of abstracting active hydrogen from the 1,3-dicarbonyl compound such as sodium carbonate. Usually, a solvent such as ethoxyethanol or dichloromethane capable of dissolving the binuclear complex as the raw material is used, but if the ligand is in liquid form, it is also possible to carry out the reaction without a solvent. There is no particular limit to the reaction temperature, but it is usually carried out within the range of 0°C to 200°C.

[0115] [ka]

[0116] In the third step, the diketonato complex is reacted with a ligand, usually at least one equivalent. There is no particular restriction on the type and amount of the solvent, and if the ligand is liquid at the reaction temperature, no solvent is necessary. There is no particular restriction on the reaction temperature, but since the reactivity is somewhat poor, the reaction is often carried out at a relatively high temperature of 100°C to 300°C. Therefore, a solvent with a high boiling point, such as glycerin, is preferably used. After the final reaction, purification is performed to remove unreacted raw materials, reaction by-products, and solvents. Although purification procedures in ordinary organic synthesis chemistry can be applied, purification is mainly performed by normal phase silica gel column chromatography as described in the above non-patent literature. As the developing solution, a single or mixed solution of hexane, heptane, dichloromethane, chloroform, ethyl acetate, toluene, methyl ethyl ketone, and methanol can be used. Purification may be performed multiple times under different conditions. Other chromatographic techniques, such as reversed phase silica gel chromatography, size exclusion chromatography, and paper chromatography, as well as purification procedures such as separation washing, reprecipitation, recrystallization, suspension washing of powder, and drying under reduced pressure, can be performed as necessary.

[0117] <Uses of iridium complex compounds> The iridium complex compound according to this embodiment can be suitably used as a material for use in an organic electroluminescent device, i.e., as a red light-emitting material for an organic electroluminescent device, and can also be suitably used as a light-emitting material for an organic electroluminescent device or other light-emitting devices.

[0118] [Iridium complex compound-containing composition] The iridium complex compound according to the present embodiment has excellent solubility in a solvent, and is therefore preferably used together with a solvent. Hereinafter, the composition according to the present embodiment containing the iridium complex compound according to the present embodiment and a solvent (hereinafter, sometimes referred to as the "iridium complex compound-containing composition") will be described.

[0119] The iridium complex compound-containing composition according to the present embodiment contains the above-mentioned iridium complex compound and solvent. The iridium complex compound-containing composition according to the present embodiment is usually used to form a layer or film by a wet film-forming method, and is preferably used to form an organic layer of an organic electroluminescent device. The organic layer is preferably a light-emitting layer. In other words, the iridium complex compound-containing composition is preferably a composition for an organic electroluminescent device, and is particularly preferably used as a composition for forming a light-emitting layer.

[0120] The content of the iridium complex compound according to the present embodiment in the iridium complex compound-containing composition is usually 0.001% by mass or more, preferably 0.01% by mass or more, and usually 99.9% by mass or less, preferably 99% by mass or less. By setting the content of the iridium complex compound in the iridium complex compound-containing composition within this range, holes and electrons can be efficiently injected from adjacent layers, such as a hole transport layer or a hole blocking layer, to the light-emitting layer, thereby reducing the driving voltage. The iridium complex compound according to the present embodiment may be contained in the iridium complex compound-containing composition alone or in a combination of two or more types.

[0121] When the iridium complex compound-containing composition according to this embodiment is used in, for example, an organic electroluminescent device, it may contain, in addition to the above-mentioned iridium complex compound and solvent, a charge transport compound used in the organic electroluminescent device, particularly in the light-emitting layer. When the iridium complex compound-containing composition according to this embodiment is used to form a light-emitting layer of an organic electroluminescent device, it is preferable that the iridium complex compound according to this embodiment is used as a light-emitting material and another charge-transporting compound is contained as a charge-transporting host material.

[0122] (solvent) The solvent contained in the iridium complex compound-containing composition of the present embodiment is a volatile liquid component used for forming a layer containing an iridium complex compound by wet film formation, and is preferably an organic solvent. The solvent is not particularly limited as long as it is an organic solvent in which the charge transporting compound described below dissolves well, since the iridium complex compound according to the present embodiment, which is a solute, has high solvent solubility.Preferred solvents include, for example, alkanes such as n-decane, cyclohexane, ethylcyclohexane, decalin, and bicyclohexane; aromatic hydrocarbons such as toluene, xylene, mesitylene, phenylcyclohexane, and tetralin; halogenated aromatic hydrocarbons such as chlorobenzene, dichlorobenzene, and trichlorobenzene; and aromatic ethers such as 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, anisole, phenetole, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 2,3-dimethylanisole, 2,4-dimethylanisole, and diphenyl ether. aromatic esters such as phenyl acetate, phenyl propionate, methyl benzoate, ethyl benzoate, propyl benzoate, n-butyl benzoate, etc., alicyclic ketones such as cyclohexanone, cyclooctanone, fenchone, etc.; alicyclic alcohols such as cyclohexanol, cyclooctanol, etc.; aliphatic ketones such as methyl ethyl ketone, dibutyl ketone, etc.; aliphatic alcohols such as butanol, hexanol, etc.; aliphatic ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol-1-monomethyl ether acetate (PGMEA), etc.

[0123] Among these, alkanes and aromatic hydrocarbons are preferable, and in particular, phenylcyclohexane has a viscosity and boiling point suitable for the wet film formation process. These solvents may be used alone or in any combination of two or more in any ratio. The boiling point of the solvent used is usually 80° C. or higher, preferably 100° C. or higher, more preferably 120° C. or higher, and is usually 270° C. or lower, preferably 250° C. or lower, more preferably 230° C. or lower. By setting the boiling point at the lower limit of this range, it is possible to suppress a decrease in film formation stability due to solvent evaporation from the iridium complex compound-containing composition during wet film formation.

[0124] The content of the solvent in the iridium complex compound-containing composition is preferably 1% by mass or more, more preferably 10% by mass or more, particularly preferably 50% by mass or more, and preferably 99.99% by mass or less, more preferably 99.9% by mass or less, particularly preferably 99% by mass or less. The thickness of the light-emitting layer is usually about 3 to 200 nm, and by having the content of the solvent be equal to or more than this lower limit, the viscosity of the composition becomes too high, which can prevent the film-forming workability from decreasing. On the other hand, by having the content be equal to or less than this upper limit, the film tends to be easily formed in terms of the thickness of the film obtained by removing the solvent after the film is formed.

[0125] Other charge transport compounds that may be contained in the iridium complex compound-containing composition according to this embodiment may be those that have been used as materials for organic electroluminescent devices in the past.For example, pyridine, carbazole, naphthalene, perylene, pyrene, anthracene, chrysene, naphthacene, phenanthrene, coronene, fluoranthene, benzophenanthrene, fluorene, acetonaphthofluoranthene, coumarin, p-bis(2-phenylethenyl)benzene and their derivatives, quinacridone derivatives, DCM (4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran)-based compounds, benzopyran derivatives, rhodamine derivatives, benzothioxanthene derivatives, azabenzothioxanthene, condensed aromatic ring compounds substituted with arylamino groups, styryl derivatives substituted with arylamino groups, etc. may be mentioned.

[0126] These may be used alone or in any combination of two or more in any ratio. The content of other charge transport compounds in the iridium complex compound-containing composition is usually 1,000 parts by mass or less, preferably 100 parts by mass or less, and more preferably 50 parts by mass or less, and is usually 0.01 parts by mass or more, preferably 0.1 parts by mass or more, and more preferably 1 part by mass or more, relative to 1 part by mass of the iridium complex compound according to this embodiment in the iridium complex compound-containing composition.

[0127] The iridium complex compound-containing composition according to the present embodiment may contain other compounds in addition to the above compounds, etc., as necessary. For example, in addition to the above solvents, another solvent may be contained. Examples of such solvents include amides such as N,N-dimethylformamide and N,N-dimethylacetamide, and dimethylsulfoxide. These may be used alone or in any combination and ratio of two or more.

[0128] [Assist Dopant] The iridium complex compound-containing composition according to this embodiment may further contain a compound represented by the following formula (3). The compound represented by formula (3) functions as an assist dopant in the light-emitting layer of an organic electroluminescent device. The compound represented by formula (3) has a shorter maximum emission wavelength than the iridium complex compound represented by formula (1) which serves as the light-emitting dopant described above. Therefore, when the assist dopant represented by formula (3) is excited, energy transfer occurs to the light-emitting dopant represented by formula (1) which has a smaller excitation energy, and the light-emitting dopant represented by formula (1) is excited, and light emission from the light-emitting dopant represented by formula (1) is observed. The compound represented by formula (3) may be one type or may be multiple types. The compound serving as an assist dopant may contain a compound serving as an assist dopant other than the compound represented by formula (3). In this case, the total content of the compound represented by formula (3) is preferably 50% by mass or more, more preferably 100% by mass, based on the total amount of the compounds serving as an assist dopant. In other words, it is more preferable that the assist dopant is only the compound represented by formula (3).

[0129] In addition, it is preferable that the composition ratio of the iridium complex compound represented by formula (1) is equal to or greater than the composition ratio of the compound represented by formula (3) in terms of parts by mass. This makes it possible to suppress direct light emission from the assist dopant represented by formula (3), and energy is transferred from the assist dopant represented by formula (3) to the light-emitting dopant represented by formula (1) with high efficiency. Therefore, light emission from the light-emitting dopant can be obtained with high efficiency.

[0130] [ka]

[0131] In the above formula (3), R 35 is an alkyl group having 1 to 20 carbon atoms, a (hetero)aralkyl group having 7 to 40 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a (hetero)aryloxy group having 3 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, an arylsilyl group having 6 to 20 carbon atoms, an alkylcarbonyl group having 2 to 20 carbon atoms, an arylcarbonyl group having 7 to 20 carbon atoms, an alkylamino group having 1 to 20 carbon atoms, an arylamino group having 6 to 20 carbon atoms, or a (hetero)aryl group having 3 to 30 carbon atoms. These groups may further have a substituent. R 35 When multiple are present, they may be the same or different. c is an integer from 0 to 4. Ring A is any one of a pyridine ring, a pyrazine ring, a pyrimidine ring, an imidazole ring, an oxazole ring, a thiazole ring, a quinoline ring, an isoquinoline ring, a quinazoline ring, a quinoxaline ring, an azatriphenylene ring, a carboline ring, a benzothiazole ring, and a benzoxazole ring.

[0132] Ring A may have a substituent. Such a substituent is a fluorine atom, a chlorine atom, a bromine atom, an alkyl group having 1 to 20 carbon atoms, a (hetero)aralkyl group having 7 to 40 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a (hetero)aryloxy group having 3 to 20 carbon atoms, an alkylsilyl group in which the alkyl group has 1 to 20 carbon atoms, an arylsilyl group in which the aryl group has 6 to 20 carbon atoms, an alkylcarbonyl group having 2 to 20 carbon atoms, an arylcarbonyl group having 7 to 20 carbon atoms, an alkylamino group having 2 to 20 carbon atoms, an arylamino group having 6 to 20 carbon atoms, or a (hetero)aryl group having 3 to 20 carbon atoms. Adjacent substituents bonded to the ring A may be bonded to each other to form a further ring. When there are multiple rings A, they may be the same or different. L 2 represents an organic ligand, and n is an integer of 1 to 3.

[0133] R 35 The substituent which may further be possessed by is preferably a substituent selected from the substituent group Z1 described below. R 35 From the viewpoint of durability, is more preferably an alkyl group having 1 to 20 carbon atoms, a (hetero)aralkyl group having 7 to 40 carbon atoms, an arylamino group having 6 to 20 carbon atoms, or a (hetero)aryl group having 3 to 30 carbon atoms, and further preferably an alkyl group having 1 to 20 carbon atoms, a (hetero)aralkyl group having 7 to 40 carbon atoms, or a (hetero)aryl group having 3 to 20 carbon atoms. R 35 is preferably a phenyl group which may have a substituent and which is bonded to the m-position of ring A and the p-position of iridium from the viewpoints of durability and solubility. That is, it is preferable to include a compound represented by the following formula (3-1). The optional substituent is preferably a substituent selected from the substituent group Z1 described later.

[0134] [ka]

[0135] [In the above formula (3-1), rings A and L 2 , n represents rings A and L in formula (3).2 , n, respectively. R 36 is an alkyl group having 1 to 20 carbon atoms, a (hetero)aralkyl group having 7 to 40 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a (hetero)aryloxy group having 3 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, an arylsilyl group having 6 to 20 carbon atoms, an alkylcarbonyl group having 2 to 20 carbon atoms, an arylcarbonyl group having 7 to 20 carbon atoms, an alkylamino group having 1 to 20 carbon atoms, an arylamino group having 6 to 20 carbon atoms, or a (hetero)aryl group having 3 to 30 carbon atoms. These groups may further have a substituent. R 36 When multiple are present, they may be the same or different. f is an integer from 0 to 5.

[0136] R 36 The substituent which may further be possessed by is preferably a substituent selected from the substituent group Z1 described below. In terms of ease of production, f is preferably 0, and in terms of durability and enhanced solubility, f is preferably 1 or 2, and more preferably 1. From the viewpoint of durability, ring A is preferably a pyridine ring, a pyrimidine ring, or an imidazole ring, and more preferably a pyridine ring.

[0137] From the viewpoints of durability and enhanced solubility, the hydrogen atom on ring A is preferably substituted with an alkyl group having 1 to 20 carbon atoms, a (hetero)aralkyl group having 7 to 40 carbon atoms, or a (hetero)aryl group having 3 to 20 carbon atoms. From the viewpoint of ease of production, the hydrogen atom on ring A is preferably not substituted. Since the hydrogen atom on ring A is likely to generate excitons when used as an organic electroluminescent device, from the viewpoint of enhanced luminous efficiency, the hydrogen atom on ring A is preferably substituted with a phenyl group or naphthyl group which may have a substituent.

[0138] As the ring A, a quinoline ring, an isoquinoline ring, a quinazoline ring, a quinoxaline ring, an azatriphenylene ring, or a carboline ring is preferable in that excitons are easily generated on the assist dopant and the luminous efficiency is improved. Among them, a quinoline ring, an isoquinoline ring, or a quinazoline ring is preferable in terms of durability.

[0139] L 2 is an organic ligand, and is not particularly limited, but is preferably a monovalent bidentate ligand, and more preferably, L 1 The preferred examples of the two organic ligands L 2 When present, the organic ligand L 2 may have different structures. When n is 3, L 2 does not exist.

[0140] Preferred specific examples of the compound represented by formula (3) that serves as an assist dopant contained in the composition for organic electroluminescent elements according to this embodiment other than those shown in the examples are shown below, but the present invention is not limited to these.

[0141] [ka]

[0142] [Substituent group Z1] As the substituent, an alkyl group, an aralkyl group, a heteroaralkyl group, an alkoxy group, an aryloxy group, a heteroaryloxy group, an alkylsilyl group, an arylsilyl group, an alkylcarbonyl group, an arylcarbonyl group, an alkylamino group, an arylamino group, an aryl group, or a heteroaryl group can be used. Preferred are alkyl groups having 1 to 20 carbon atoms, aralkyl groups having 7 to 40 carbon atoms, heteroaralkyl groups having 7 to 40 carbon atoms, alkoxy groups having 1 to 20 carbon atoms, aryloxy groups having 6 to 20 carbon atoms, heteroaryloxy groups having 3 to 20 carbon atoms, alkylsilyl groups having 1 to 20 carbon atoms, arylsilyl groups having 6 to 20 carbon atoms, alkylcarbonyl groups having 2 to 20 carbon atoms, arylcarbonyl groups having 7 to 20 carbon atoms, alkylamino groups having 1 to 20 carbon atoms, arylamino groups having 6 to 20 carbon atoms, aryl groups having 6 to 30 carbon atoms, and heteroaryl groups having 3 to 30 carbon atoms, and more specifically, the substituents described in [Specific examples of substituents] below. More preferred are alkyl groups having 1 to 20 carbon atoms, aralkyl groups having 7 to 40 carbon atoms, alkoxy groups having 1 to 20 carbon atoms, aryloxy groups having 6 to 20 carbon atoms, and aryl groups having 6 to 30 carbon atoms.

[0143] [Specific examples of substituents] Specific examples of the substituents in the above-mentioned compound structures and the substituents in the substituent group Z1 are as follows. The alkyl group having 1 to 20 carbon atoms may be any of linear, branched, and cyclic alkyl groups. More specifically, it includes methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-octyl, isopropyl, isobutyl, isopentyl, t-butyl, and cyclohexyl groups. Among them, linear alkyl groups having 1 to 8 carbon atoms, such as methyl, ethyl, n-butyl, n-hexyl, and n-octyl groups, are preferred.

[0144] The (hetero)aralkyl group having 7 to 40 carbon atoms refers to a group in which some of the hydrogen atoms constituting a linear alkyl group, a branched alkyl group, or a cyclic alkyl group are substituted with an aryl group or a heteroaryl group. More specifically, it includes a 2-phenyl-1-ethyl group, a cumyl group, a 5-phenyl-1-pentyl group, a 6-phenyl-1-hexyl group, a 7-phenyl-1-heptyl group, and a tetrahydronaphthyl group. Among them, a 5-phenyl-1-pentyl group, a 6-phenyl-1-hexyl group, and a 7-phenyl-1-heptyl group are preferred.

[0145] Specific examples of the alkoxy group having 1 to 20 carbon atoms include a methoxy group, an ethoxy group, a propyloxy group, an isopropyloxy group, a hexyloxy group, a cyclohexyloxy group, an octadecyloxy group, etc. Of these, a hexyloxy group is preferable.

[0146] Specific examples of the (hetero)aryloxy group having 3 to 20 carbon atoms include a phenoxy group, a 4-methylphenyloxy group, etc. Among these, the phenoxy group is preferable.

[0147] Specific examples of the alkylsilyl group having 1 to 20 carbon atoms include a trimethylsilyl group, a triethylsilyl group, a triisopropylsilyl group, a dimethylphenyl group, a t-butyldimethylsilyl group, a t-butyldiphenylsilyl group, etc. Among these, a triisopropyl group, a t-butyldimethylsilyl group, and a t-butyldiphenylsilyl group are preferred.

[0148] Specific examples of the arylsilyl group having 6 to 20 carbon atoms include a diphenylpyridylsilyl group, a triphenylsilyl group, etc. Among these, a triphenylsilyl group is preferable.

[0149] Specific examples of the alkylcarbonyl group having 2 to 20 carbon atoms include an acetyl group, a propionyl group, a pivaloyl group, a caproyl group, a decanoyl group, a cyclohexylcarbonyl group, etc. Among these, an acetyl group and a pivaloyl group are preferable.

[0150] Specific examples of the arylcarbonyl group having 7 to 20 carbon atoms include a benzoyl group, a naphthoyl group, an anthrayl group, etc. Of these, a benzoyl group is preferable.

[0151] Specific examples of the alkylamino group having 1 to 20 carbon atoms include a methylamino group, a dimethylamino group, a diethylamino group, an ethylmethylamino group, a dihexylamino group, a dioctylamino group, a dicyclohexylamino group, etc. Among these, a dimethylamino group and a dicyclohexylamino group are preferable.

[0152] Specific examples of the arylamino group having 6 to 20 carbon atoms include a phenylamino group, a diphenylamino group, a di(4-tolyl)amino group, a di(2,6-dimethylphenyl)amino group, etc. Among these, a diphenylamino group and a di(4-tolyl)amino group are preferable.

[0153] The (hetero)aryl group having 3 to 30 carbon atoms means an aromatic hydrocarbon group having one free valence, an aromatic heterocyclic group, a linked aromatic hydrocarbon group in which a plurality of aromatic hydrocarbons are linked, a linked aromatic heterocyclic group in which a plurality of aromatic heterocyclic groups are linked, or a group in which at least one aromatic hydrocarbon and at least one aromatic heterocycle are arbitrarily linked. Specific examples thereof include a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a perylene ring, a tetracene ring, a pyrene ring, a benzpyrene ring, a chrysene ring, a triphenylene ring, a fluoranthene ring, a furan ring, a benzofuran ring, a dibenzofuran ring, a thiophene ring, a benzothiophene ring, a dibenzothiophene ring, a pyrrole ring, a pyrazole ring, an imidazole ring, an oxadiazole ring, an indole ring, a carbazole ring, a pyrroloimi ring, and a pyrrole ring. Examples of the linked aromatic hydrocarbon group in which a plurality of aromatic hydrocarbons are linked together include a biphenyl group, a terphenyl group, and the like.

[0154] Among the (hetero)aryl groups, from the viewpoint of durability, a benzene ring, a naphthalene ring, a dibenzofuran ring, a dibenzothiophene ring, a carbazole ring, a pyridine ring, a pyrimidine ring, or a triazine ring, each having one free valence, is preferred, and among these, an aryl group having 6 to 18 carbon atoms, such as a benzene ring, a naphthalene ring, or a phenanthrene ring, each having one free valence and which may be substituted with an alkyl group having 1 to 8 carbon atoms, or a pyridine ring, each having one free valence and which may be substituted with an alkyl group having 1 to 4 carbon atoms, is more preferred, and an aryl group having 6 to 18 carbon atoms, such as a benzene ring, a naphthalene ring, or a phenanthrene ring, each having one free valence and which may be substituted with an alkyl group having 1 to 8 carbon atoms, is even more preferred.

[0155] When a group in a compound has multiple substituents, the combination of these substituents can be, but is not limited to, for example, an aryl group and an alkyl group, an aryl group and an aralkyl group, or an aryl group and an alkyl group or an aralkyl group. For example, the combination of an aryl group and an aralkyl group can be a combination of a benzene, biphenyl, or terphenyl group and a 5-phenyl-1-pentyl or 6-phenyl-1-hexyl group.

[0156] [Maximum emission wavelength] The method for measuring the maximum emission wavelength of the iridium complex compound in this embodiment will be described below. The maximum emission wavelength of an iridium complex compound can be determined from the photoluminescence spectrum of a solution in which the material is dissolved in an organic solvent, or from the photoluminescence spectrum of a thin film of the material alone. In the case of solution photoluminescence, the compound is dissolved in an organic solvent such as toluene at room temperature at a concentration of 1 × 10 -4 mol / L or less, preferably at a concentration of 1×10 -5The photoluminescence spectrum of the solution dissolved at mol / L is measured using a spectrophotometer (Organic EL quantum yield measurement device C9920-02 manufactured by Hamamatsu Photonics KK) The wavelength showing the maximum value of the obtained spectrum intensity is defined as the maximum emission wavelength. In the case of thin film photoluminescence, a thin film is prepared by vacuum deposition or solution coating of a material, and photoluminescence is measured using the above-mentioned spectrophotometer. The wavelength showing the maximum value of the obtained emission spectrum intensity is regarded as the maximum emission wavelength. The maximum emission wavelengths of the compound used as the light-emitting dopant and the compound used as the assist dopant must be determined by the same method and compared.

[0157] The compound represented by formula (3), which serves as an assist dopant contained in the composition for organic electroluminescent elements according to this embodiment, has a maximum emission wavelength that is shorter than that of the iridium complex compound represented by formula (1), which serves as an emitting dopant. The maximum emission wavelength of the compound serving as the light-emitting dopant is preferably 580 nm or more, more preferably 590 nm or more, even more preferably 600 nm or more, and is preferably 700 nm or less, more preferably 680 nm or less. When the maximum emission wavelength is in this range, a preferable color of the red light-emitting material suitable for an organic electroluminescent device tends to be expressed. The maximum emission wavelength of the compound serving as the assist dopant and the maximum emission wavelength of the compound serving as the luminescent dopant are preferably at least 10 nm apart, or at most 50 nm apart, in order to allow efficient energy transfer, and such a difference is more preferably at most 40 nm.

[0158] The iridium complex compound represented by formula (1) is preferably contained in the same amount as or more than the compound represented by formula (3). That is, the composition ratio of the iridium complex compound represented by formula (1) in terms of parts by mass is preferably equal to or greater than the composition ratio of the compound represented by formula (3). It is more preferable that the iridium complex compound represented by formula (1) is contained in an amount of 1 to 3 times the amount of the compound represented by formula (3) in terms of parts by mass. In terms of the luminous efficiency and long life of the element, it is particularly preferable to contain 1 to 2 times. In terms of obtaining more vivid light emission, it is even more preferable to contain 2 times or more. In terms of reducing the driving voltage of the element, it is even more preferable to contain less than 2 times. This allows energy from the assist dopant to be transferred to the luminous dopant more efficiently, resulting in high luminous efficiency and a long life of the element.

[0159] [Compound represented by formula (20)] The iridium complex compound-containing composition according to this embodiment preferably further contains a compound represented by the following formula (20).

[0160] [ka]

[0161] [In the above formula (20), Each W independently represents CH or N, and at least one W is N; Xa 1 , Ya 1 , and Za 1 each independently represents a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent, or a divalent aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent, Xa 2 , Ya 2 and Za 2 each independently represents a hydrogen atom, an aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent, or an aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent, g11, h11, and j11 each independently represent an integer of 0 to 6; At least one of g11, h11, and j11 is an integer of 1 or more; If g11 is 2 or more, multiple Xa 1 may be the same or different, If h11 is 2 or more, multiple Ya 1 may be the same or different, If j11 is 2 or more, multiple Za 1 may be the same or different, R 23 represents a hydrogen atom or a substituent, and four R 23 may be the same or different, However, if g11, h11, or j11 is 0, the corresponding Xa 2 , Ya 2 , or Za 2 is not a hydrogen atom.)

[0162] The compound represented by the above formula (20) is preferably a charge transport compound, that is, a charge transport host material.

[0163] <w> In the formula (20), W represents CH or N, and at least one of them is N. From the viewpoints of electron transport properties and electron durability, it is preferable that at least two of them are N, and it is more preferable that all of them are N.

[0164] <Xa 1 , Ya 1 , Za 1 , Xa 2 , Ya 2 , Za 2 > In the formula (20), Xa 1 , Ya 1 , Za 1 is a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent, and 2 , Ya 2 , Za 2 When is an aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent, the aromatic hydrocarbon ring of the aromatic hydrocarbon group having 6 to 30 carbon atoms is preferably a 6-membered monocyclic ring or 2 to 5 condensed rings. Specific examples include a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a fluorene ring, a perylene ring, a tetracene ring, a pyrene ring, a benzpyrene ring, a chrysene ring, a triphenylene ring, a fluoranthene ring, and an indenofluorene ring. Among these, a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, or a fluorene ring is preferred, a benzene ring, a naphthalene ring, a phenanthrene ring, or a fluorene ring is more preferred, and a benzene ring, a naphthalene ring, or a fluorene ring is even more preferred.

[0165] In the formula (20), Xa 1 , Ya 1 , Za 1 is a divalent aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent, and 2 , Ya 2 , Za 2 When is an aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent, the aromatic heterocycle of the aromatic heterocyclic group having 3 to 30 carbon atoms is preferably a 5- or 6-membered monocyclic ring or a 2- to 5-membered fused ring. Specific examples thereof include a furan ring, a benzofuran ring, a dibenzofuran ring, a thiophene ring, a benzothiophene ring, a dibenzothiophene ring, a pyrrole ring, a pyrazole ring, an imidazole ring, an oxadiazole ring, an indole ring, a carbazole ring, an indolocarbazole ring, an indenocarbazole ring, a pyrroloimidazole ring, a pyrrolopyrazole ring, a pyrrolopyrrole ring, a thienopyrrole ring, a thienothiophene ring, a furopyrrole ring, a furofuran ring, a thienofuran ring, a benzisoxazole ring, a benzisothiazole ring, a benzimidazole ring, a pyridine ring, a pyrazine ring, a pyridazine ring, a pyrimidine ring, a triazine ring, a quinoline ring, an isoquinoline ring, a cinnoline ring, a quinoxaline ring, a perimidine ring, a quinazoline ring, a quinazolinone ring, and a phenanthroline ring. Among these, a thiophene ring, a pyrrole ring, an imidazole ring, a pyridine ring, a pyrimidine ring, a triazine ring, a quinoline ring, a quinazoline ring, a carbazole ring, a dibenzofuran ring, a dibenzothiophene ring, an indolocarbazole ring, a phenanthroline ring, or an indenocarbazole ring is preferred, a pyridine ring, a pyrimidine ring, a triazine ring, a quinoline ring, a quinazoline ring, a carbazole ring, a dibenzofuran ring, or a dibenzothiophene ring is more preferred, and a carbazole ring, a dibenzofuran ring, or a dibenzothiophene ring is even more preferred.

[0166] Xa in the formula (20) 1 , Ya 1 , Za 1 , Xa 2 , Ya 2 , and Za 2 In the above formula, particularly preferred aromatic hydrocarbon rings are a benzene ring, a naphthalene ring, or a phenanthrene ring, and particularly preferred aromatic heterocycles are a carbazole ring, a dibenzofuran ring, or a dibenzothiophene ring.

[0167] <g11、h11、j11> g11, h11, and j11 each independently represent an integer of 0 to 6, and at least one of g11, h11, and j11 is an integer of 1 or more. From the viewpoint of charge transport properties and durability, it is preferable that g11 is 2 or more, or at least one of h11 and j11 is 3 or more. If g11 is 2 or more, multiple Xa 1 may be the same or different. When h11 is 2 or more, multiple Ya 1 may be the same or different. In addition, when j11 is 2 or more, multiple Za 1 may be the same or different.

[0168] Also, if g11 is 0, the corresponding Xa 2 is not a hydrogen atom, g11 is 0, that is, Xa 1 If Xa does not exist, 2 means an aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent, or an aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent. Similarly, when h11 is 0, that is, Ya 1 If does not exist, Ya 2 means an aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent, or an aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent. 1 If does not exist, Za 2 means an aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent, or an aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent.

[0169] In addition, the compound represented by the formula (20) preferably has a total of 8 to 18 of these rings, including the ring having three central Ws, from the viewpoints of charge transportability, durability, and solubility in organic solvents.

[0170] <R 23 > R when it is a substituent 23 is preferably an aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent, or an aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent. From the viewpoint of improving durability and charge transportability, an aromatic hydrocarbon group which may have a substituent is more preferable. When R is a substituent, 23 When a plurality of are present, they may be different from each other.

[0171] The above-mentioned substituents which the aromatic hydrocarbon group having 6 to 30 carbon atoms may have, the substituents which the aromatic heterocyclic group having 3 to 30 carbon atoms may have, and the substituent R 23 The substituent that may be possessed by may be selected from the following substituent group Z2.

[0172] <Substituent group Z2> The substituent group Z2 is a group consisting of an alkyl group, an alkoxy group, an aryloxy group, a heteroaryloxy group, an alkoxycarbonyl group, a dialkylamino group, a diarylamino group, an arylalkylamino group, an acyl group, a halogen atom, a haloalkyl group, an alkylthio group, an arylthio group, a silyl group, a siloxy group, a cyano group, an aromatic hydrocarbon group, and an aromatic heterocyclic group. These substituents may have any of a linear, branched, and cyclic structure.

[0173] More specifically, the substituent group Z2 includes the following structures. For example, linear, branched, or cyclic alkyl groups having a carbon number of usually 1 or more, preferably 4 or more, and usually 24 or less, preferably 12 or less, more preferably 8 or less, and even more preferably 6 or less, such as a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, a sec-butyl group, a tert-butyl group, an n-hexyl group, a cyclohexyl group, or a dodecyl group; For example, an alkoxy group, such as a methoxy group or an ethoxy group, having usually 1 or more and usually 24 or less, preferably 12 or less, carbon atoms; For example, an aryloxy group or heteroaryloxy group, such as a phenoxy group, a naphthoxy group, or a pyridyloxy group, which usually has 4 or more, preferably 5 or more, and usually has 36 or less, preferably 24 or less, carbon atoms; For example, alkoxycarbonyl groups having usually 2 or more and usually 24 or less, preferably 12 or less, carbon atoms, such as a methoxycarbonyl group or an ethoxycarbonyl group; For example, dialkylamino groups having usually 2 or more and usually 24 or less, preferably 12 or less, carbon atoms, such as a dimethylamino group or a diethylamino group; For example, diarylamino groups having usually 10 or more, preferably 12 or more, and usually 36 or less, preferably 24 or less, such as a diphenylamino group and a ditolylamino group; For example, an arylalkylamino group having usually 7 or more and usually 36 or less, preferably 24 or less, carbon atoms, such as a phenylmethylamino group; For example, acyl groups such as an acetyl group and a benzoyl group, each of which usually has 2 or more carbon atoms and usually has 24 or less carbon atoms, and preferably has 12 or less carbon atoms; For example, halogen atoms such as fluorine atoms and chlorine atoms; For example, haloalkyl groups having typically 1 or more and typically 12 or less, preferably 6 or less, carbon atoms, such as a trifluoromethyl group; For example, an alkylthio group, such as a methylthio group or an ethylthio group, having usually 1 or more and usually 24 or less, preferably 12 or less, carbon atoms; For example, an arylthio group having usually 4 or more, preferably 5 or more, and usually 36 or less, preferably 24 or less, such as a phenylthio group, a naphthylthio group, or a pyridylthio group; For example, a silyl group having a carbon number of usually 2 or more, preferably 3 or more, and usually 36 or less, preferably 24 or less, such as a trimethylsilyl group or a triphenylsilyl group; For example, a siloxy group having a carbon number of usually 2 or more, preferably 3 or more, and usually 36 or less, preferably 24 or less, such as a trimethylsiloxy group or a triphenylsiloxy group; Cyano group; For example, aromatic hydrocarbon groups such as a phenyl group and a naphthyl group, each of which usually has 6 or more carbon atoms and usually has 36 or less carbon atoms, and preferably has 24 or less carbon atoms; For example, aromatic heterocyclic groups having usually 3 or more, preferably 4 or more, and usually 36 or less, preferably 24 or less, such as a thienyl group or a pyridyl group.

[0174] Among the above-mentioned substituent group Z2, preferred are alkyl groups, alkoxy groups, diarylamino groups, aromatic hydrocarbon groups, and aromatic heterocyclic groups. From the viewpoint of charge transportability, the substituent is preferably an aromatic hydrocarbon group or an aromatic heterocyclic group, more preferably an aromatic hydrocarbon group, and even more preferably has no substituent. From the viewpoint of improving solubility, the substituent is preferably an alkyl group or an alkoxy group.

[0175] Each of the substituents in the above-mentioned substituent group Z2 may further have a substituent. Examples of the substituent include the same ones as those in the above-mentioned substituent group Z2. Each of the substituents that may be contained in the above-mentioned substituent group Z2 is preferably an alkyl group having 8 or less carbon atoms, an alkoxy group having 8 or less carbon atoms, or a phenyl group, more preferably an alkyl group having 6 or less carbon atoms, an alkoxy group having 6 or less carbon atoms, or a phenyl group, and from the viewpoint of charge transportability, each of the substituents in the above-mentioned substituent group Z2 more preferably does not have an additional substituent.

[0176] <Molecular weight> The compound represented by the formula (20) is a low molecular weight material, and the molecular weight is preferably 3,000 or less, more preferably 2,500 or less, particularly preferably 2,000 or less, and most preferably 1,500 or less. The lower limit of the molecular weight is usually 300 or more, preferably 350 or more, and more preferably 400 or more.

[0177] <Specific examples of the compound represented by formula (20)> The compound represented by formula (20) is not particularly limited, but examples thereof include the following compounds.

[0178] [ka]

[0179] [ka]

[0180] The iridium complex compound-containing composition according to this embodiment may contain only one type of compound represented by the formula (20), or may contain two or more types.

[0181] [Organic electroluminescent device] The organic electroluminescent device according to this embodiment contains the iridium complex compound according to this embodiment. The organic electroluminescent device according to the present embodiment preferably has at least an anode, a cathode, and at least one organic layer located between the anode and the cathode on a substrate, and at least one of the organic layers contains the iridium complex compound according to the present embodiment. The organic layer includes a light-emitting layer. In the organic electroluminescent device according to the present embodiment, the light-emitting layer contains the iridium complex compound according to the present embodiment.

[0182] The light-emitting layer of the organic electroluminescent device according to this embodiment preferably contains the assist dopant in addition to the iridium complex compound according to this embodiment. The reason why the assist dopant is preferably contained is as described above. The light-emitting layer of the organic electroluminescent device according to this embodiment preferably further contains the compound represented by formula (20) in addition to the iridium complex compound according to this embodiment. The reason why it is preferable to further contain the compound represented by formula (20) is as described above. The light-emitting layer of the organic electroluminescent device according to this embodiment preferably contains the compound represented by formula (20) and the assist dopant in addition to the iridium complex compound according to this embodiment.

[0183] The organic layer containing the iridium complex compound according to the present embodiment is more preferably a layer formed using the iridium complex compound-containing composition according to the present embodiment, and even more preferably a layer formed by a wet film-forming method. The layer formed by the wet film-forming method is preferably the light-emitting layer. In the present embodiment, the wet film formation method refers to a film formation method, i.e., a coating method, which employs a wet film formation method such as a spin coating method, a dip coating method, a die coating method, a bar coating method, a blade coating method, a roll coating method, a spray coating method, a capillary coating method, an inkjet method, a nozzle printing method, a screen printing method, a gravure printing method, a flexographic printing method, etc., and dries the film formed by these methods to form a film.

[0184] FIG. 1 is a schematic cross-sectional view showing a suitable structural example of an organic electroluminescent device 10 according to this embodiment. In FIG. 1, reference numeral 1 denotes a substrate, reference numeral 2 denotes an anode, reference numeral 3 denotes a hole injection layer, reference numeral 4 denotes a hole transport layer, reference numeral 5 denotes a light-emitting layer, reference numeral 6 denotes a hole blocking layer, reference numeral 7 denotes an electron transport layer, reference numeral 8 denotes an electron injection layer, and reference numeral 9 denotes a cathode. The materials applied to these structures can be known materials and are not particularly limited, but representative materials and manufacturing methods for each layer are described below as examples. In addition, when publications, papers, etc. are cited, the relevant contents are assumed to be applicable and applicable as appropriate within the scope of common sense of a person skilled in the art.

[0185] <Substrate 1> The substrate 1 is a support for the organic electroluminescent element, and is usually made of a quartz or glass plate, a metal plate or metal foil, a plastic film or sheet, or the like. Of these, a glass plate or a plate made of a transparent synthetic resin such as polyester, polymethacrylate, polycarbonate, or polysulfone is preferred. The substrate 1 is preferably made of a material with high gas barrier properties, since the organic electroluminescent element is less likely to deteriorate due to the outside air. For this reason, when a material with low gas barrier properties such as a synthetic resin substrate is used, it is preferred to provide a dense silicon oxide film or the like on at least one side of the substrate 1 to increase the gas barrier properties.

[0186] <Anode 2> The anode 2 has a function of injecting holes into the layer on the light-emitting layer side. The anode 2 is usually made of a metal such as aluminum, gold, silver, nickel, palladium, or platinum, a metal oxide such as an oxide of at least one of indium and tin, a metal halide such as copper iodide, or a conductive polymer such as carbon black, poly(3-methylthiophene), polypyrrole, or polyaniline.

[0187] The anode 2 is usually formed by a dry method such as sputtering or vacuum deposition. When the anode 2 is formed using fine metal particles such as silver, fine particles such as copper iodide, carbon black, fine conductive metal oxide particles, fine conductive polymer powder, or the like, the anode 2 can be formed by dispersing the particles in an appropriate binder resin solution and applying the solution to the substrate. When using a conductive polymer, the anode 2 can be formed by forming a thin film directly on the substrate by electrolytic polymerization, or by applying the conductive polymer to the substrate (Appl. Phys. Lett., Vol. 60, p. 2711, 1992).

[0188] The anode 2 usually has a single-layer structure, but may have a laminated structure as appropriate. When the anode 2 has a laminated structure, a different conductive material may be laminated on the first anode layer. The thickness of the anode 2 may be determined according to the required transparency, material, etc. When particularly high transparency is required, a thickness that provides a visible light transmittance of 60% or more is preferable, and a thickness that provides a visible light transmittance of 80% or more is more preferable. The thickness of the anode 2 is usually 5 nm or more, preferably 10 nm or more, and usually 1000 nm or less, preferably 500 nm or less. On the other hand, when transparency is not required, the thickness of the anode 2 may be any thickness depending on the required strength, etc., and in this case, the anode 2 may have the same thickness as the substrate 1. When a film is formed on the surface of the anode 2, it is preferable to perform a treatment with ultraviolet light + ozone, oxygen plasma, argon plasma, or the like before the film formation in order to remove impurities on the anode and to adjust its ionization potential to improve the hole injection property.

[0189] <Hole injection layer 3> A layer having a function of transporting holes from the anode 2 side to the light-emitting layer 5 side is usually called a hole injection transport layer or a hole transport layer. When there are two or more layers having a function of transporting holes from the anode 2 side to the light-emitting layer 5 side, the layer closer to the anode 2 side may be called a hole injection layer 3. The hole injection layer 3 is preferably used in order to enhance the function of transporting holes from the anode 2 to the light-emitting layer 5 side. When the hole injection layer 3 is used, the hole injection layer 3 is usually formed on the anode 2.

[0190] The thickness of the hole injection layer 3 is usually 1 nm or more, preferably 5 nm or more, and usually 1000 nm or less, preferably 500 nm or less. The hole injection layer 3 may be formed by a vacuum deposition method or a wet film formation method, but is preferably formed by a wet film formation method in terms of excellent film formability. The hole injection layer 3 preferably contains a hole transporting compound, more preferably contains a hole transporting compound and an electron accepting compound, and further preferably contains a cation radical compound, particularly preferably contains a cation radical compound and a hole transporting compound.

[0191] (Hole transport compound) The hole injection layer forming composition usually contains a hole transporting compound that will become the hole injection layer 3. In addition, in the case of a wet film forming method, it usually further contains a solvent. It is preferable that the hole injection layer forming composition has high hole transporting properties and can efficiently transport injected holes. For this reason, it is preferable that the hole mobility is large and impurities that become traps are unlikely to occur during production or use. It is also preferable that the composition has excellent stability, a small ionization potential, and high transparency to visible light. In particular, when the hole injection layer 3 is in contact with the light emitting layer 5, it is preferable that the composition does not quench the light emission from the light emitting layer 5 or does not form an exciplex with the light emitting layer 5 to reduce the light emitting efficiency.

[0192] The hole transport compound is preferably a compound having an ionization potential of 4.5 eV to 6.0 eV from the viewpoint of the charge injection barrier from the anode 2 to the hole injection layer 3. Examples of the hole transport compound include aromatic amine compounds, phthalocyanine compounds, porphyrin compounds, oligothiophene compounds, polythiophene compounds, benzylphenyl compounds, compounds in which a tertiary amine is linked via a fluorene group, hydrazone compounds, silazane compounds, and quinacridone compounds.

[0193] Among the above-mentioned exemplary compounds, aromatic amine compounds are preferred from the viewpoint of amorphousness and visible light transmittance, and aromatic tertiary amine compounds are particularly preferred. Here, the aromatic tertiary amine compounds are compounds having an aromatic tertiary amine structure, and also include compounds having a group derived from an aromatic tertiary amine. The type of aromatic tertiary amine compound is not particularly limited, but it is preferable to use a polymeric compound having a weight average molecular weight of 1000 to 1,000,000, i.e., a polymeric compound having a series of repeating units, because it is easy to obtain uniform light emission due to the surface smoothing effect. Preferred examples of aromatic tertiary amine polymeric compounds include polymeric compounds having a repeating unit represented by the following formula (I).

[0194] [ka]

[0195] (In the above formula (I), Ar 1 and Ar 2 each independently represents an aromatic group which may have a substituent or a heteroaromatic group which may have a substituent. Ar 3 ~Ar 5 each independently represents an aromatic group which may have a substituent or a heteroaromatic group which may have a substituent. Q represents a linking group selected from the group of linking groups shown below. In addition, Ar 1 ~Ar 5 Among these, two groups bonded to the same N atom may be bonded to each other to form a ring. The linking groups are shown below.

[0196] [ka]

[0197] (In each of the above formulas, Ar 6 ~Ar 16 R each independently represents an aromatic group which may have a substituent or a heteroaromatic group which may have a substituent. a ~R b Each independently represents a hydrogen atom or an arbitrary substituent.

[0198] Ar 1 ~Ar 16 As the aromatic group and heteroaromatic group, from the viewpoints of the solubility, heat resistance, and hole injection and transport properties of the polymer compound, groups derived from a benzene ring, a naphthalene ring, a phenanthrene ring, a thiophene ring, and a pyridine ring are preferred, and groups derived from a benzene ring and a naphthalene ring are more preferred. Specific examples of the aromatic tertiary amine polymeric compound having a repeating unit represented by formula (I) include those described in WO 2005 / 089024.

[0199] (Electron Accepting Compound) The hole injection layer 3 preferably contains an electron accepting compound because the conductivity of the hole injection layer 3 can be improved by oxidation of the hole transporting compound. As the electron-accepting compound, a compound having an oxidizing power and the ability to accept one electron from the above-mentioned hole-transporting compound is preferred. Specifically, a compound having an electron affinity of 4 eV or more is preferred, and a compound having an electron affinity of 5 eV or more is more preferred.

[0200] Examples of such electron-accepting compounds include one or more compounds selected from the group consisting of triarylboron compounds, metal halides, Lewis acids, organic acids, onium salts, salts of arylamines and metal halides, and salts of arylamines and Lewis acids.Specific examples include onium salts substituted with organic groups such as 4-isopropyl-4'-methyldiphenyliodonium tetrakis(pentafluorophenyl)borate and triphenylsulfonium tetrafluoroborate (International Publication No. 2005 / 089024); high-valence inorganic compounds such as iron(III) chloride (Japanese Patent Application Laid-Open No. 11-251067) and ammonium peroxodisulfate; cyano compounds such as tetracyanoethylene; aromatic boron compounds such as tris(pentafluorophenyl)borane (Japanese Patent Application Laid-Open No. 2003-31365); fullerene derivatives, and iodine.

[0201] (Cation radical compound) The cation radical compound is preferably an ionic compound consisting of a cation radical, which is a chemical species obtained by removing one electron from a hole transporting compound, and a counter anion. However, when the cation radical is derived from a hole transporting polymer compound, the cation radical has a structure in which one electron is removed from a repeating unit of the polymer compound.

[0202] The cation radical is preferably a chemical species obtained by removing one electron from the compound described above as the hole transport compound, which is preferable in terms of amorphousness, visible light transmittance, heat resistance, solubility, etc. Here, the cation radical compound can be generated by mixing the above-mentioned hole transporting compound and the electron accepting compound. That is, by mixing the above-mentioned hole transporting compound and the electron accepting compound, electrons are transferred from the hole transporting compound to the electron accepting compound, and a cation ion compound consisting of the cation radical of the hole transporting compound and a counter anion is generated.

[0203] Cation radical compounds derived from polymeric compounds such as PEDOT / PSS (Adv. Mater., 2000, Vol. 12, p. 481) and emeraldine hydrochloride (J. Phys. Chem., 1990, Vol. 94, p. 7716) can also be produced by oxidative polymerization, i.e., dehydrogenative polymerization. The oxidative polymerization referred to here is a method in which a monomer is chemically or electrochemically oxidized in an acidic solution using peroxodisulfate or the like. In the case of this oxidative polymerization (dehydrogenative polymerization), the monomer is oxidized to polymerize, and a cation radical is generated by removing one electron from the repeating unit of the polymer, with the anion derived from the acidic solution as the counter anion.

[0204] (Formation of hole injection layer 3 by wet film formation method) When forming the hole injection layer 3 by a wet film formation method, a material for the hole injection layer 3 is usually mixed with a soluble solvent, i.e., a hole injection layer solvent, to prepare a composition for forming a hole injection layer. This composition for forming a hole injection layer is formed into a layer corresponding to the lower layer of the hole injection layer 3, usually on the anode 2, by a wet film formation method, and then dried to form the layer. The formed film can be dried in the same manner as in the formation of the light emitting layer 5 by a wet film formation method.

[0205] The concentration of the hole transport compound in the composition for forming a hole injection layer may be any concentration as long as it does not significantly impair the effects of the present invention, but a lower concentration is preferable in terms of uniformity of the film thickness, while a higher concentration is preferable in terms of preventing defects from occurring in the hole injection layer 3. Specifically, the concentration is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, and particularly preferably 0.5% by mass or more, and is preferably 70% by mass or less, more preferably 60% by mass or less, and particularly preferably 50% by mass or less.

[0206] Examples of the solvent include ether-based solvents, ester-based solvents, aromatic hydrocarbon-based solvents, and amide-based solvents. Examples of the ether solvent include aliphatic ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, and propylene glycol-1-monomethyl ether acetate (PGMEA), and aromatic ethers such as 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, anisole, phenetole, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 2,3-dimethylanisole, and 2,4-dimethylanisole.

[0207] Examples of the ester solvent include aromatic esters such as phenyl acetate, phenyl propionate, methyl benzoate, ethyl benzoate, propyl benzoate, and n-butyl benzoate. Examples of aromatic hydrocarbon solvents include toluene, xylene, cyclohexylbenzene, 3-isopropylbiphenyl, 1,2,3,4-tetramethylbenzene, 1,4-diisopropylbenzene, and methylnaphthalene.

[0208] Examples of the amide solvent include N,N-dimethylformamide and N,N-dimethylacetamide. In addition, dimethyl sulfoxide and the like can also be used. The formation of the hole injection layer 3 by a wet film formation method is usually carried out by preparing a composition for forming a hole injection layer, applying the composition to form a film on a layer corresponding to the lower layer of the hole injection layer 3, usually on the anode 2, and drying the film. After the formation of the hole injection layer 3, the applied film is usually dried by heating, drying under reduced pressure, or the like.

[0209] (Formation of Hole Injection Layer 3 by Vacuum Deposition Method) When forming the hole injection layer 3 by the vacuum deposition method, usually, one or more of the constituent materials of the hole injection layer 3, i.e., the above-mentioned hole transport compound, electron accepting compound, etc., are placed in a crucible installed in a vacuum chamber, and the inside of the vacuum chamber is vacuumed by a vacuum pump for 10 -4 After evacuating to about 100 Pa, the crucible is heated to evaporate the material in the crucible while controlling the amount of evaporation, and a hole injection layer 3 is formed on the anode 2 on the substrate placed facing the crucible. When two or more types of materials are used, the materials constituting the hole injection layer 3 are usually placed in separate crucibles, and heating is also performed for each crucible. Furthermore, evaporation is usually performed independently while controlling the amount of evaporation. On the other hand, when two or more types of materials are used, a mixture of those materials can also be placed in one crucible and heated and evaporated to form the hole injection layer 3.

[0210] The degree of vacuum during deposition is not limited as long as it does not significantly impair the effects of the present invention. -6 Torr (0.13×10 -4 Pa) or more, and is usually 9.0×10 -6 Torr (12.0 × 10 -4 The deposition rate is not limited as long as it does not significantly impair the effects of the present invention, but is usually 0.1 Å / sec or more and usually 5.0 Å / sec or less. The deposition temperature during deposition is not limited as long as it does not significantly impair the effects of the present invention, but is preferably 10° C. or more and preferably 50° C. or less.

[0211] <Hole transport layer 4> The hole transport layer 4 is a layer that transports holes from the anode 2 side to the light emitting layer 5 side. The hole transport layer 4 is not an essential layer in the organic electroluminescent device of the present invention, but it is preferable to provide this layer in terms of enhancing the function of transporting holes from the anode 2 to the light emitting layer 5. When the hole transport layer 4 is provided, the hole transport layer 4 is usually formed between the anode 2 and the light emitting layer 5. When the above-mentioned hole injection layer 3 is present, it is formed between the hole injection layer 3 and the light emitting layer 5.

[0212] The thickness of the hole transport layer 4 is usually 5 nm or more, preferably 10 nm or more, and usually 300 nm or less, preferably 100 nm or less. The hole transport layer 4 may be formed by a vacuum deposition method or a wet film formation method, but is preferably formed by a wet film formation method in terms of excellent film formability. The hole transport layer 4 usually contains a hole transporting compound that becomes the hole transport layer 4. Examples of the hole transporting compound contained in the hole transport layer 4 include aromatic diamines containing two or more tertiary amines and having two or more condensed aromatic rings substituted with nitrogen atoms, such as 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (JP Patent Publication No. 5-234681), and aromatic amine compounds having a starburst structure, such as 4,4',4''-tris(1-naphthylphenylamino)triphenylamine (J. Lumi n., vol. 72-74, p. 985, 1997), aromatic amine compounds consisting of triphenylamine tetramers (Chem. Commun., p. 2175, 1996), spiro compounds such as 2,2',7,7'-tetrakis-(diphenylamino)-9,9'-spirobifluorene (Synth. Metals, vol. 91, p. 209, 1997), carbazole derivatives such as 4,4'-N,N'-dicarbazolebiphenyl, etc. In addition, for example, polyvinylcarbazole, polyvinyltriphenylamine (JP Patent Publication 7-53953 A), polyarylene ether sulfone containing tetraphenylbenzidine (Polym. Adv. Tech., vol. 7, p. 33, 1996), etc. can also be preferably used.

[0213] (Formation of hole transport layer 4 by wet film formation method) When the hole transport layer 4 is formed by a wet film formation method, it is usually formed using a composition for forming a hole transport layer instead of the composition for forming a hole injection layer, in the same manner as when the above-mentioned hole injection layer 3 is formed by a wet film formation method. When the hole transport layer 4 is formed by a wet film formation method, the composition for forming a hole transport layer usually further contains a solvent. The solvent used in the composition for forming a hole transport layer may be the same as the solvent used in the composition for forming a hole injection layer described above. The concentration of the hole transporting compound in the composition for forming a hole transport layer can be in the same range as the concentration of the hole transporting compound in the composition for forming a hole injection layer. The hole transport layer 4 can be formed by a wet film formation method similar to the film formation method for the hole injection layer 3 described above.

[0214] (Formation of Hole Transport Layer 4 by Vacuum Deposition Method) When the hole transport layer 4 is formed by the vacuum deposition method, it can be formed in the same manner as when the hole injection layer 3 is formed by the vacuum deposition method, using the material of the hole transport layer 4 instead of the material of the hole injection layer 3. The film formation conditions such as the degree of vacuum, deposition rate, and temperature during deposition can be the same as those during the vacuum deposition of the hole injection layer 3.

[0215] <Light-emitting layer 5> The light-emitting layer 5 is a layer that is excited by the recombination of holes injected from the anode 2 and electrons injected from the cathode 9 when an electric field is applied between the pair of electrodes, and thus emits light. The light-emitting layer 5 is a layer formed between the anode 2 and the cathode 9. When the hole injection layer 3 is present on the anode 2, the light-emitting layer 5 is formed between the hole injection layer 3 and the cathode 9. When the hole transport layer 4 is present on the anode 2, the light-emitting layer 5 is formed between the hole transport layer 4 and the cathode 9.

[0216] The thickness of the light-emitting layer 5 is arbitrary as long as it does not significantly impair the effects of the present invention, but a thicker layer is preferable in terms of preventing defects from occurring in the film, and a thinner layer is preferable in terms of making it easier to achieve a low driving voltage. Therefore, the thickness of the light-emitting layer 5 is preferably 3 nm or more, more preferably 5 nm or more, and usually is preferably 200 nm or less, more preferably 100 nm or less.

[0217] The light-emitting layer 5 contains at least a material having a light-emitting property (light-emitting material), and preferably also contains a material having a charge transport property (charge transport material). As the light-emitting material, any of the light-emitting layers may contain the iridium complex compound according to this embodiment, and other light-emitting materials may be used as appropriate. Hereinafter, light-emitting materials other than the iridium complex compound according to this embodiment will be described in detail.

[0218] (Light Emitting Materials) The light-emitting material is not particularly limited as long as it emits light at a desired emission wavelength and does not impair the effects of the present invention, and any known light-emitting material can be used. The light-emitting material may be a fluorescent material or a phosphorescent material, but a material with good luminous efficiency is preferred, and a phosphorescent material is preferred from the viewpoint of internal quantum efficiency.

[0219] Examples of the fluorescent material include the following materials. Examples of fluorescent light-emitting materials that emit blue light (blue fluorescent light-emitting materials) include naphthalene, perylene, pyrene, anthracene, coumarin, chrysene, p-bis(2-phenylethenyl)benzene, and derivatives thereof. Examples of fluorescent materials that emit green light (green fluorescent materials) include quinacridone derivatives, coumarin derivatives, and aluminum complexes such as Al(C9H6NO)3.

[0220] Examples of fluorescent light-emitting materials that give yellow light emission (yellow fluorescent light-emitting materials) include rubrene and perimidon derivatives. Examples of fluorescent materials that emit red light (red fluorescent materials) include DCM (4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran) compounds, benzopyran derivatives, rhodamine derivatives, benzothioxanthene derivatives, and azabenzothioxanthene.

[0221] Examples of phosphorescent materials include organometallic complexes containing a metal selected from Groups 7 to 11 of the long-form periodic table (hereinafter, unless otherwise specified, the term "periodic table" refers to the long-form periodic table). Preferred examples of metals selected from Groups 7 to 11 of the periodic table include ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum, and gold.

[0222] As the ligand of the organometallic complex, 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, is preferred, and a phenylpyridine ligand or a phenylpyrazole ligand is particularly preferred. Here, the (hetero)aryl represents an aryl group or a heteroaryl group.

[0223] Specific examples of preferred phosphorescent materials include phenylpyridine complexes such as tris(2-phenylpyridine)iridium, tris(2-phenylpyridine)ruthenium, tris(2-phenylpyridine)palladium, bis(2-phenylpyridine)platinum, tris(2-phenylpyridine)osmium, and tris(2-phenylpyridine)rhenium; and porphyrin complexes such as octaethylplatinum porphyrin, octaphenylplatinum porphyrin, octaethylpalladium porphyrin, and octaphenylpalladium porphyrin.

[0224] Examples of polymer-based luminescent materials include polyfluorene-based materials such as poly(9,9-dioctylfluorene-2,7-diyl), poly[(9,9-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl))diphenylamine)], and poly[(9,9-dioctylfluorene-2,7-diyl)-co-(1,4-benzo-2{2,1'-3}-triazole)], and polyphenylenevinylene-based materials such as poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene].

[0225] (Charge transport material) The charge transporting material is a material having a positive charge, i.e., a hole transporting property, or a negative charge, i.e., an electron transporting property, and is not particularly limited as long as it does not impair the effects of the present invention, and known materials can be used. As the charge transporting material, compounds conventionally used in the light emitting layer 5 of an organic electroluminescent device can be used, and in particular, compounds used as a host material for the light emitting layer 5 are preferred.

[0226] Specific examples of the charge transporting material include aromatic amine compounds, phthalocyanine compounds, porphyrin compounds, oligothiophene compounds, polythiophene compounds, benzylphenyl compounds, compounds in which a tertiary amine is linked via a fluorene group, hydrazone compounds, silazane compounds, silanamine compounds, phosphamine compounds, and quinacridone compounds, which are exemplified as the hole transporting compound for the hole injection layer 3. Other examples include electron transporting compounds such as anthracene compounds, pyrene compounds, carbazole compounds, pyridine compounds, phenanthroline compounds, oxadiazole compounds, and silole compounds.

[0227] Further, for example, aromatic diamines containing two or more tertiary amines, such as 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl, in which two or more condensed aromatic rings are substituted with nitrogen atoms (JP Patent Publication 5-234681), aromatic amine compounds having a starburst structure, such as 4,4',4''-tris(1-naphthylphenylamino)triphenylamine (J. Lumin., vol. 72-74, p. 985, 1997), triphenylamine, etc. Also preferably usable are the compounds exemplified as hole-transporting compounds for the hole-transporting layer 4, such as aromatic amine compounds consisting of a tetramer of fluorene (Chem. Commun., p. 2175, 1996), fluorene compounds such as 2,2',7,7'-tetrakis-(diphenylamino)-9,9'-spirobifluorene (Synth. Metals, vol. 91, p. 209, 1997), and carbazole compounds such as 4,4'-N,N'-dicarbazolebiphenyl. Other examples include oxadiazole compounds such as 2-(4-biphenylyl)-5-(p-tert-butylphenyl)-1,3,4-oxadiazole (tBu-PBD) and 2,5-bis(1-naphthyl)-1,3,4-oxadiazole (BND); silole compounds such as 2,5-bis(6'-(2',2"-bipyridyl))-1,1-dimethyl-3,4-diphenylsilole (PyPySPyPy); and phenanthroline compounds such as bathophenanthroline (BPhen) and 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP, bathocuproine).

[0228] (Formation of light-emitting layer 5 by wet film formation method) The method for forming the light-emitting layer 5 may be a vacuum deposition method or a wet film formation method, but the wet film formation method is preferred because of its excellent film-forming properties. When the light-emitting layer 5 is formed by a wet film-forming method, it is usually formed using a composition for forming a light-emitting layer prepared by mixing a material for the light-emitting layer 5 with a soluble solvent, i.e., a solvent for the light-emitting layer, instead of a composition for forming a hole-injection layer, in the same manner as in the case of forming the hole-injection layer 3 described above by a wet film-forming method. In this embodiment, it is preferable to use the iridium complex compound-containing composition according to this embodiment described above as the composition for forming the light-emitting layer.

[0229] Examples of the solvent include ether-based solvents, ester-based solvents, aromatic hydrocarbon-based solvents, and amide-based solvents as mentioned above for forming the hole injection layer 3, as well as alkane-based solvents, halogenated aromatic hydrocarbon-based solvents, aliphatic alcohol-based solvents, alicyclic alcohol-based solvents, aliphatic ketone-based solvents, and alicyclic ketone-based solvents. The solvents used are as exemplified for the iridium complex compound-containing composition according to the present embodiment, and specific examples of the solvent are listed below, but are not limited thereto as long as they do not impair the effects of the present invention.

[0230] For example, aliphatic ether solvents such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, and propylene glycol-1-monomethyl ether acetate (PGMEA); aromatic ether solvents such as 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, anisole, phenetole, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 2,3-dimethylanisole, 2,4-dimethylanisole, and diphenyl ether; aromatic ester solvents such as phenyl acetate, phenyl propionate, methyl benzoate, ethyl benzoate, propyl benzoate, and n-butyl benzoate; toluene, xylene, mesitylene, cyclohexylbenzene, tetralin, and 3-isopropyl biphenyl. Examples of the solvent include aromatic hydrocarbon solvents such as phenyl, 1,2,3,4-tetramethylbenzene, 1,4-diisopropylbenzene, and methylnaphthalene; amide solvents such as N,N-dimethylformamide and N,N-dimethylacetamide; alkane solvents such as n-decane, cyclohexane, ethylcyclohexane, decalin, and bicyclohexane; halogenated aromatic hydrocarbon solvents such as chlorobenzene, dichlorobenzene, and trichlorobenzene; aliphatic alcohol solvents such as butanol and hexanol; alicyclic alcohol solvents such as cyclohexanol and cyclooctanol; aliphatic ketone solvents such as methyl ethyl ketone and dibutyl ketone; and alicyclic ketone solvents such as cyclohexanone, cyclooctanone, and fenchone. Among these, alkane solvents and aromatic hydrocarbon solvents are particularly preferred.

[0231] In order to obtain a more uniform film, it is preferable that the solvent evaporates at an appropriate rate from the liquid film immediately after the film formation. Therefore, as described above, the boiling point of the solvent used is usually 80°C or higher, preferably 100°C or higher, more preferably 120°C or higher, and usually 270°C or lower, preferably 250°C or lower, more preferably 230°C or lower. The amount of the solvent used is arbitrary as long as it does not significantly impair the effects of the present invention, but the total content in the composition for forming the light-emitting layer, i.e., the iridium complex compound-containing composition, is preferably high in terms of ease of film formation due to low viscosity, and is preferably low in terms of ease of film formation in a thick film. As described above, the content of the solvent in the iridium complex compound-containing composition is preferably 1 mass% or more, more preferably 10 mass% or more, particularly preferably 50 mass% or more, and preferably 99.99 mass% or less, more preferably 99.9 mass% or less, particularly preferably 99 mass% or less.

[0232] The solvent can be removed after the wet film formation by heating or reducing pressure. In the heating method, a clean oven or a hot plate is preferable as a heating means for applying heat uniformly to the entire film. The heating temperature in the heating step is arbitrary as long as it does not significantly impair the effects of the present invention, but a higher temperature is preferable in terms of shortening the drying time, and a lower temperature is preferable in terms of less damage to the material. The upper limit of the heating temperature is usually 250°C or less, preferably 200°C or less, and more preferably 150°C or less. The lower limit of the heating temperature is usually 30°C or more, preferably 50°C or more, and more preferably 80°C or more. By setting the upper limit temperature as above, it is within the range of the heat resistance of the charge transport material or phosphorescent material that is usually used, and decomposition and crystallization are suppressed, which is preferable. By setting the lower limit temperature as above, it is preferable that the solvent does not take too long to remove. The heating time in the heating step is appropriately determined depending on the boiling point and vapor pressure of the solvent in the composition for forming the light-emitting layer, the heat resistance of the material, and the heating conditions.

[0233] (Formation of the light-emitting layer 5 by vacuum deposition method) When forming the light-emitting layer 5 by the vacuum deposition method, usually, one or more of the constituent materials of the light-emitting layer 5, i.e., the above-mentioned light-emitting material, charge-transporting compound, etc., are placed in a crucible placed in a vacuum chamber, and the inside of the vacuum chamber is vacuumed by a vacuum pump for 10 -4 After evacuating to about 10 Pa, the crucible is heated to evaporate the materials in the crucible while controlling the amount of evaporation, and the light-emitting layer 5 is formed on the hole injection layer 3 or the hole transport layer 4 placed opposite the crucible. When two or more types of materials are used, the materials constituting the light-emitting layer 5 are usually placed in separate crucibles, and heating is also performed for each crucible. Furthermore, evaporation is usually performed independently while controlling the amount of evaporation. On the other hand, when two or more types of materials are used, a mixture of those materials can also be placed in one crucible and heated and evaporated to form the light-emitting layer 5.

[0234] The degree of vacuum during deposition is not limited as long as it does not significantly impair the effects of the present invention. -6 Torr (0.13×10 -4 Pa) or more, and is usually 9.0×10 -6 Torr (12.0 × 10 -4 The deposition rate is not limited as long as it does not significantly impair the effects of the present invention, but is usually 0.1 Å / sec or more and usually 5.0 Å / sec or less. The deposition temperature during deposition is not limited as long as it does not significantly impair the effects of the present invention, but is preferably 10° C. or more and preferably 50° C. or less.

[0235] <Hole blocking layer 6> A hole blocking layer 6 may be provided between the light emitting layer 5 and the electron injection layer 8 described below. The hole blocking layer 6 is a layer laminated on the light emitting layer 5 so as to be in contact with the interface of the light emitting layer 5 on the cathode 9 side. This hole-blocking layer 6 has a role of preventing holes migrating from the anode 2 from reaching the cathode 9, and a role of efficiently transporting electrons injected from the cathode 9 toward the light-emitting layer 5. Required physical properties of the material constituting the hole-blocking layer 6 include high electron mobility and low hole mobility, a large energy gap, i.e., a large difference between HOMO and LUMO, and a high excited triplet level (T1).

[0236] Examples of materials for the hole blocking layer 6 that satisfy these conditions include mixed ligand complexes such as bis(2-methyl-8-quinolinolato)(phenolato)aluminum and bis(2-methyl-8-quinolinolato)(triphenylsilanolate)aluminum; Kinorinolato )aluminum-μ-oxo-bis-(2-methyl-8-quinolinolato)aluminum binuclear metal complex and other metal complexes, styryl compounds such as distyrylbiphenyl derivatives (JP Patent Publication No. 11-242996), triazole derivatives such as 3-(4-biphenylyl)-4-phenyl-5(4-tert-butylphenyl)-1,2,4-triazole (JP Patent Publication No. 7-41759), and phenanthroline derivatives such as bathocuproine (JP Patent Publication No. 10-79297). Furthermore, compounds having at least one pyridine ring substituted at the 2-, 4-, and 6-positions, as described in International Publication No. 2005 / 022962, are also preferred as materials for the hole blocking layer 6.

[0237] There is no limitation on the method for forming the hole blocking layer 6, and it can be formed in the same manner as the above-mentioned method for forming the light emitting layer 5. The thickness of the hole blocking layer 6 is arbitrary as long as it does not significantly impair the effects of the present invention, but is usually 0.3 nm or more, preferably 0.5 nm or more, and usually 100 nm or less, preferably 50 nm or less.

[0238] <Electron transport layer 7> The electron transport layer 7 is formed to further improve the current efficiency of the device by transporting the electrons from the light emitting layer 5 or the hole transport layer 6. prevention It is provided between layer 6 and electron injection layer 8 . The electron transport layer 7 is made of a compound capable of efficiently transporting electrons injected from the cathode 9 between the electrodes to which an electric field is applied, toward the light emitting layer 5. The electron transporting compound used in the electron transport layer 7 is required to have a high efficiency of electron injection from the cathode 9 or the electron injection layer 8, and to have high electron mobility so as to efficiently transport the injected electrons.

[0239] Specific examples of electron transport compounds that satisfy such conditions include metal complexes such as aluminum complexes of 8-hydroxyquinoline (JP-A-59-194393), metal complexes of 10-hydroxybenzo[h]quinoline, oxadiazole derivatives, distyrylbiphenyl derivatives, silole derivatives, 3-hydroxyflavone metal complexes, 5-hydroxyflavone metal complexes, benzoxazole metal complexes, benzothiazole metal complexes, trisbenzimidazolylbenzene (U.S. Pat. No. 5,645,948), quinoxaline compounds (JP-A-6-207169), phenanthroline derivatives (JP-A-5-331459), 2-t-butyl-9,10-N,N'-dicyanoanthraquinone diimine, n-type hydrogenated amorphous silicon carbide, n-type zinc sulfide, and n-type zinc selenide.

[0240] The thickness of the electron transport layer 7 is usually 1 nm or more, preferably 5 nm or more, and usually 300 nm or less, preferably 100 nm or less. The electron transport layer 7 is formed by laminating it on the light emitting layer 5 or the hole blocking layer 6 by a wet film formation method or a vacuum deposition method in the same manner as the light emitting layer 5. Usually, the vacuum deposition method is used.

[0241] <Electron injection layer 8> The electron injection layer 8 plays a role of efficiently injecting electrons injected from the cathode 9 into the electron transport layer 7 or the light emitting layer 5 . To efficiently inject electrons, a metal having a low work function is preferable as the material for forming the electron injection layer 8. Examples of such a material include alkali metals such as sodium and cesium, and alkaline earth metals such as barium and calcium.

[0242] The thickness of the electron injection layer 8 is preferably 0.1 to 5 nm. Also, inserting an extremely thin insulating film of LiF, MgF2, Li2O, Cs2CO3, etc. as an electron injection layer 8 into the interface between the cathode 9 and the electron transport layer 7 is an effective method for improving the efficiency of the element (Appl. Phys. Lett., vol. 70, p. 152, 1997; JP-A-10-74586; IEEE Trans. Electron. Devices, vol. 44, p. 1245, 1997; SID 04 Digest, p. 154). The extremely thin insulating film is an insulating film having a thickness of about 0.1 to 5 nm.

[0243] Furthermore, doping an organic electron transport material, such as a nitrogen-containing heterocyclic compound such as bathophenanthroline or a metal complex such as an aluminum complex of 8-hydroxyquinoline, with an alkali metal such as sodium, potassium, cesium, lithium, or rubidium (as described in JP-A-10-270171, JP-A-2002-100478, JP-A-2002-100482, etc.) is preferable because it improves electron injection and transport properties and makes it possible to achieve both excellent film quality. In this case, the film thickness is usually 5 nm or more, preferably 10 nm or more, and usually 200 nm or less, preferably 100 nm or less. The electron injection layer 8 is formed by laminating it on the light-emitting layer 5 or the hole blocking layer 6 or the electron transport layer 7 thereon by a wet film formation method or a vacuum deposition method in the same manner as the light-emitting layer 5. The details of the wet film formation method are the same as those of the light-emitting layer 5 described above.

[0244] <Cathode 9> The cathode 9 plays a role of injecting electrons into the layer on the light-emitting layer 5 side, i.e., the electron injection layer 8 or the light-emitting layer 5. The material of the cathode 9 can be the material used for the anode 2, but in order to efficiently inject electrons, it is preferable to use a metal with a low work function, such as tin, magnesium, indium, calcium, aluminum, silver, or an alloy thereof. Specific examples include low-work-function alloy electrodes such as a magnesium-silver alloy, a magnesium-indium alloy, and an aluminum-lithium alloy.

[0245] From the viewpoint of stability of the element, it is preferable to protect the cathode 9 made of a metal having a low work function by laminating a metal layer having a high work function and stable against the atmosphere on the cathode 9. Examples of the metal to be laminated include aluminum, silver, copper, nickel, chromium, gold, platinum, and the like. The thickness of the cathode is usually the same as that of the anode 2 .

[0246] <Other constituent layers> The above has mainly been described with respect to the element having the layer structure shown in FIG. 1 . However, in the organic electroluminescent element according to this embodiment, any layer may be present between the anode 2 and the cathode 9 and the light-emitting layer 5 in addition to the layers described above, as long as the performance is not impaired. Furthermore, any layer other than the light-emitting layer 5 may be omitted.

[0247] For example, a hole blocking layer 6 For the same purpose, it is also effective to provide an electron blocking layer between the hole transport layer 4 and the light emitting layer 5. The electron blocking layer prevents the electrons moving from the light emitting layer 5 from reaching the hole transport layer 4, thereby increasing the probability of recombination with holes in the light emitting layer 5 and trapping the generated excitons in the light emitting layer 5, and also efficiently transports the holes injected from the hole transport layer 4 toward the light emitting layer 5.

[0248] The properties required for the electron blocking layer include high hole transportability, a large energy gap, i.e., a large difference between HOMO and LUMO, and a high excited triplet level (T1). When the light emitting layer 5 is formed by a wet film formation method, it is preferable to also form the electron blocking layer by the wet film formation method, since this makes it easier to manufacture the device. For this reason, it is preferable that the electron blocking layer also has compatibility with wet film formation, and examples of materials used for such electron blocking layers include copolymers of dioctylfluorene and triphenylamine, such as F8-TFB (International Publication No. 2004 / 084260).

[0249] It is also possible to have the reverse structure to that shown in FIG. 1, that is, to laminate the cathode 9, the electron injection layer 8, the electron transport layer 7, the hole blocking layer 6, the light-emitting layer 5, the hole transport layer 4, the hole injection layer 3, and the anode 2 in this order on the substrate 1, and it is also possible to provide the organic electroluminescent device of the present invention between two substrates, at least one of which is highly transparent. Furthermore, it is possible to use a structure in which the layer configuration shown in Fig. 1 is stacked in multiple stages, i.e., a structure in which multiple light-emitting units are stacked. In that case, it is preferable from the viewpoints of luminous efficiency and driving voltage to use, in place of the interface layer between the stages between the light-emitting units, for example, when the anode is ITO and the cathode is Al, for example, to use V2O5 or the like as a charge generation layer instead of these two layers, as this reduces the barrier between the stages. The present invention can be applied to any organic electroluminescent device, whether it is a single device, a device having a structure in which the devices are arranged in an array, or a structure in which the anodes and cathodes are arranged in an XY matrix.

[0250] [Display and lighting devices] The organic EL display device and organic EL lighting device according to the present embodiment include the organic electroluminescence element according to the present embodiment as described above. The type and structure of the organic EL display device and organic EL lighting device according to the present embodiment are not particularly limited, and they can be assembled according to a conventional method using the organic electroluminescence element according to the present embodiment. For example, the organic EL display device and organic EL lighting device according to this embodiment can be formed by a method such as that described in "Organic EL Display" (Ohmsha, published on August 20, 2004, by Tokito Shizuo, Adachi Chinaya, and Murata Hideyuki). EXAMPLES

[0251] The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to the following examples, and the present invention can be practiced with any modifications without departing from the gist of the present invention. In the following synthesis examples, all reactions were carried out under a nitrogen stream. Solvents and solutions used in the reactions were degassed by an appropriate method such as nitrogen bubbling.

[0252] [Synthesis of Iridium Complex Compounds] <Synthesis Example 1: Synthesis of Compound D-1>

[0253] [ka]

[0254] 2-Bromofluorene (20.4g) and dehydrated tetrahydrofuran (500mL) were placed in a 1L eggplant flask, and tert-butoxypotassium (21.1g) was added while cooling in an ice-water bath, and 1-iodo-n-octane (50.9g) was added dropwise over 15 minutes. The ice-water bath was removed and the mixture was stirred at room temperature for 3 hours. The solvent was distilled off under reduced pressure, and water (300mL) and dichloromethane (300mL) were added for liquid separation and washing. The oil phase was collected and concentrated under reduced pressure, and the resulting residue was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 1 / 9), yielding 37.7g of 2-bromo-9,9-di(n-octyl)fluorene as a pale yellow oily substance.

[0255] [ka]

[0256] 2-Bromo-9,9-di(n-octyl)fluorene (37.7 g), bis(pinacolato)diboron (23.7 g), potassium acetate (26.0 g), dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium·dichloromethane adduct (3.0 g), and dimethylsulfoxide (DMSO) (350 mL) were placed in a 1 L eggplant flask and stirred at 85° C. for 10 hours, then at 90° C. for another 10 hours. After cooling to room temperature, water (350 mL) and dichloromethane (300 mL) were added for separation and washing. The oil phase was collected and concentrated under reduced pressure, and the resulting residue was purified by silica gel column chromatography (neutral silica gel, ethyl acetate / hexane = 0 / 1 to 1 / 9) to obtain 36.8 g of 2-[9,9-di(n-octyl)fluoren-2-yl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane as a black-brown oily substance.

[0257] [ka]

[0258] 1L eggplant flask To , 5-bromo-2-iodopyridine (9.0 g), 2-[9,9-di(n-octyl)fluoren-2-yl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (15.1 g), [tetrakis(triphenylphosphine)palladium(0)] (1.5 g), 2M tripotassium phosphate aqueous solution (40 mL), toluene (80 mL) and ethanol (40 mL) were added and stirred in an oil bath at 105 ° C for 9 hours. After cooling to room temperature, the aqueous phase was removed, and the remaining liquid was concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, ethyl acetate / hexane = 1 / 9), to obtain 9.8 g of 2-(5-bromopyridin-2-yl)-9,9-di(n-octyl)fluorene as a light green solid.

[0259] [ka]

[0260] 2-(5-bromopyridin-2-yl)-9,9-di(n-octyl)fluorene (9.8 g), bis(pinacolato)diboron (5.2 g), potassium acetate (5.5 g), dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium·dichloromethane adduct (0.6 g) and dimethylsulfoxide (100 mL) were placed in a 1 L eggplant flask and stirred at 90°C for 9 hours. After cooling to room temperature, water (500 mL) and dichloromethane (300 mL) were added for separation and washing. The oil phase was collected and concentrated under reduced pressure to obtain a residue, which was then purified by silica gel column chromatography (neutral silica gel, ethyl acetate / hexane = 15 / 85 to 3 / 7) to obtain 7.8 g of 2-[{9,9-di(n-octyl)fluoren-2-yl}pyridin-5-yl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane as a yellow solid.

[0261] [ka]

[0262] In a 1L eggplant flask, 2-[{9,9-di(n-octyl)fluoren-2-yl}pyridin-5-yl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (11.8 g), 2,4-ditert-butyl-6-chloro-1,3,5-triazine (5.4 g, synthesized by employing the method described in JP 2016-160180 A), [tetrakis(triphenylphosphine)palladium(0)] (0.9 g), 2M tripotassium phosphate aqueous solution (25 mL), toluene (60 mL) and ethanol (20 mL) were added and stirred for 2 hours in an oil bath at 105 ° C. After cooling to room temperature, the aqueous phase was removed, and the remaining liquid was concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 35 / 65), to obtain 13.5 g of intermediate 1 as a colorless amorphous substance.

[0263] [ka]

[0264] Intermediate 1 (7.1 g), iridium(III) chloride n-hydrate (1.8 g), 2-ethoxyethanol (61 mL), and water (14 mL) were added to a 200 mL recovery flask and stirred for 12 hours in an oil bath at 135 to 150° C. The residue obtained after vacuum concentration was purified by silica gel column chromatography (basic silica gel, dichloromethane), yielding 7.5 g of intermediate 2 as a red solid.

[0265] [ka]

[0266] Intermediate 2 (7.5 g), intermediate 1 (6.4 g), silver(I) trifluoromethanesulfonate (1.3 g), and diglyme (25 mL) were added to a 1 L recovery flask and stirred for 3 hours in an oil bath at 145° C. The residue obtained by vacuum concentration was purified by silica gel column chromatography (neutral silica gel, hexane / dichloromethane=8 / 2), yielding 6.2 g of compound D-1 as a red solid.

[0267] <Synthesis Example 2: Synthesis of Compound D-2>

[0268] [ka]

[0269] 2-acetylfluorene (228.1 g) and ethylene glycol (2.0 L) were placed in a 10 L four-neck reactor, and nitrogen was bubbled through for 30 minutes. Then, potassium hydroxide (216.9 g) was added, and the temperature was raised to 55°C with stirring. Then, hydrazine monohydrate (164.5 g) was added dropwise. The temperature was raised to 109°C over 1 hour and 40 minutes, and then to 129°C over 40 minutes, and the mixture was stirred at an internal temperature of 129-146°C for 6 hours. After cooling to room temperature, water (2 L) and concentrated hydrochloric acid (600 mL) were added dropwise in that order, and dichloromethane (3 L x 2 times) was added. in The collected organic phase was washed with water (2 L) and saturated saline (1 L) in that order, and the residue obtained by removing the solvent was purified by silica gel column chromatography (dichloromethane / hexane = 1 / 4), yielding 109.6 g of 2-ethylfluorene as a white solid.

[0270] [ka]

[0271] 2-Ethylfluorene (200.9 g) and propylene carbonate (2.5 L) were placed in a 10 L four-neck reactor at room temperature, and after 30 minutes of nitrogen bubbling, N-bromosuccinimide (191.5 g) was added in portions. The internal temperature was then raised to 56°C over 35 minutes, and the mixture was stirred at an internal temperature of 56-62°C for 2 hours and 40 minutes. After cooling to room temperature, the mixture was poured into water (6.3 L) and stirred for a while, followed by precipitation. thing The solid was filtered and washed with water (2.5 L x 2 times). The solid was purified by silica gel column chromatography (dichloromethane / hexane = 1 / 4) to obtain 270.6 g of 2-bromo-7-ethylfluorene as a white solid.

[0272] [ka]

[0273] 2-Bromo-7-ethylfluorene (270.6 g) and N-methylpyrrolidone (6.8 L) were placed in a 20 L four-neck reactor, and after 30 minutes of nitrogen bubbling, potassium tert-butoxide (277.9 g) was added in portions. After stirring for 30 minutes at an internal temperature of 18 to 20°C, the mixture was cooled to an internal temperature of 10°C, and 1-bromooctane (478.3 g) was added dropwise over 20 minutes at an internal temperature of 37°C or less, followed by stirring for 2 hours at an internal temperature of 30 to 37°C. After cooling to an internal temperature of 4°C, water (7 L) was added and the mixture was extracted with ethyl acetate (7 L x 2 times). The organic phases were combined and washed successively with water (4 L x 2) and saturated saline (3 L). The solvent was removed under reduced pressure and the resulting residue was purified by silica gel column chromatography (hexane) to obtain 314.8 g of 2-bromo-7-ethyl-9,9-di(n-octyl)fluorene as a yellow oily substance.

[0274] [ka]

[0275] 2-Bromo-7-ethyl-9,9-di(n-octyl)fluorene (314.8 g) and N-methylpyrrolidone (3.1 L) were placed in a 10 L four-necked reactor at room temperature and stirred for 30 minutes in a 50° C. oil bath. Then, bis(pinacolato) ) Jibolo hmm( The mixture was added with 192.8 g of ethyl acetate, 198.7 g of potassium acetate, and 20.7 g of dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium-dichloromethane adduct, and the mixture was heated to 100°C over 1.5 hours, and then stirred at 100°C for 4 hours. After cooling to room temperature, ethyl acetate (3 L) and water (3 L) were added for liquid separation and extraction. The oil phase was washed with water (2 L x 2) and saturated saline (1 L), and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (dichloromethane / hexane = 1 / 1), and 2-[7-ethyl-9,9-di(n-octyl)fluoren-2-yl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane was obtained as a white solid (248.9 g).

[0276] [ka]

[0277] In a 5L four-necked reactor, cyanuric chloride (136.9g) was dissolved in tetrahydrofuran (THF, 600mL) and cooled to -23℃. 1M-phenylmagnesium bromide·THF solution (779mL) was added dropwise over 50 minutes so that the internal temperature was within -23 to 0℃, and then the mixture was stirred overnight while gradually returning to room temperature. After that, the mixture was cooled to -20℃, and 2M-hydrochloric acid (430mL) was added dropwise over 15 minutes so that the internal temperature was within -20 to -5℃, and then the mixture was stirred for 20 minutes while returning to room temperature. After extraction with ethyl acetate (1L×2), the mixture was washed with saturated saline (500mL×2). The oil phase was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (dichloromethane / hexane=1 / 2), and 117.9g of 2,4-dichloro-6-phenyl-1,3,5-triazine was obtained as a white solid.

[0278] [ka]

[0279] In a 5L four-necked reactor, 2,4-dichloro-6-phenyl-1,3,5-triazine (117.9g) and THF (1.2L) were added and dissolved, followed by the addition of copper(I) iodide (3.0g). After cooling to an internal temperature of -35°C, 2M-tert-butylmagnesium bromide·THF solution (261mL) was added dropwise over 15 minutes at an internal temperature of -35 to -4°C, and the internal temperature was increased to 16°C over 1 hour. After cooling again to an internal temperature of -35°C, 2M-tert-butylmagnesium bromide·THF solution (78mL) was added dropwise over 15 minutes at an internal temperature of -35 to -14°C, and the internal temperature was increased to 15°C over 30 minutes. After cooling again to an internal temperature of -35°C, 2M-tert-butylmagnesium bromide·THF solution (52mL) was added dropwise over 10 minutes at an internal temperature of -35 to -26°C, and stirred at an internal temperature of 15 to 20°C for 1 hour. After cooling to an internal temperature of -15°C, 2M-hydrochloric acid (500mL) was added dropwise over 7 minutes at an internal temperature of -15 to -6°C, and stirred for a while while returning to room temperature. Extraction was performed with ethyl acetate (1.5L x 2), and the oil phase was washed with saturated saline (500mL), and the residue obtained by concentrating the oil phase under reduced pressure was purified by silica gel column chromatography (dichloromethane / hexane = 1 / 8), and 80.6g of 2-tert-butyl-4-chloro-6-phenyl-1,3,5-triazine was obtained as a white solid.

[0280] [ka]

[0281] In a 1L eggplant flask, 5-bromo-2-iodopyridine (10.9 g), 2-[7-ethyl-9,9-di(n-octyl)fluoren-2-yl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (19.8 g), [tetrakis(triphenylphosphine)palladium(0)] (2.5 g), 2M tripotassium phosphate aqueous solution (45 mL), toluene (100 mL) and ethanol (50 mL) were added and stirred for 20 hours in an oil bath at 105 ° C. After cooling to room temperature, the aqueous phase was removed, and the remaining liquid was concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, ethyl acetate / hexane = 1 / 1), to obtain 17.3 g of 2-ethyl-7-(5-bromopyridin-2-yl)-9,9-di(n-octyl)fluorene as a pale yellow solid.

[0282] [ka]

[0283] 2-Ethyl-7-(5-bromopyridin-2-yl)-9,9-di(n-octyl)fluorene (17.3 g), bis(pinacolato)diboron (9.1 g), potassium acetate (9.0 g), dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium·dichloromethane adduct (0.82 g) and dimethylsulfoxide (100 mL) were placed in a 1 L eggplant flask and stirred at 90°C for 15.5 hours. After cooling to room temperature, water (400 mL) and dichloromethane (300 mL) were added for separation and washing. The oil phase was recovered and concentrated under reduced pressure to obtain a residue, which was then purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 6 / 4 to 1 / 0, followed by ethyl acetate / dichloromethane = 1 / 4 to 1 / 1) to obtain 13.3 g of 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2-[7-ethyl-9,9-di(n-octyl)fluoren-2-yl}]pyridine as a dark brown solid.

[0284] [ka]

[0285] In a 300 mL eggplant flask, 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2-[7-ethyl-9,9-di(n-octyl)fluoren-2-yl]pyridine (8.6 g), 2-tert-butyl-4-chloro-6-phenyl-1,3,5-triazine (4.1 g), [tetrakis(triphenylphosphine)palladium(0)] (0.64 g), 2M tripotassium phosphate aqueous solution (18 mL), toluene (40 mL) and tetrahydrofuran (20 mL) were added and stirred in an oil bath at 80 ° C for 9 hours. After cooling to room temperature, the aqueous phase was removed, and the remaining liquid was concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 15 / 85 to 1 / 1) to obtain 6.7 g of intermediate 3.

[0286] [ka]

[0287] Intermediate 3 (3.8 g), iridium (III) chloride n-hydrate (0.92 g), 2-ethoxyethanol (80 mL), and water (10 mL) were added to a 200 mL recovery flask, and the mixture was stirred for 9 hours while distilling in an oil bath at 145°C. The amount of liquid distilled and extracted was 60 mL. The residue obtained by vacuum concentration was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 35 / 65), and 3.4 g of intermediate 4 was obtained as a red solid.

[0288] [ka]

[0289] In a 100 mL recovery flask, intermediate 4 (3.4 g), intermediate 3 (3.0 g), silver(I) trifluoromethanesulfonate (0.54 g), and diglyme (11 mL) were added and stirred for 5 hours in an oil bath at 145° C. The residue obtained by vacuum concentration was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane=4 / 6), yielding 3.8 g of compound D-2 as a red solid.

[0290] <Synthesis Example 3: Synthesis of Compound D-3>

[0291] [ka]

[0292] Cyanuric chloride (68.0 g) and THF (680 mL) were placed in a 3 L four-necked reactor and dissolved, then copper(I) iodide (2.1 g) was added and the internal temperature was cooled to -25° C. Then, 2M tert-butylmagnesium bromide·THF solution (277 mL) was added dropwise over 30 minutes at an internal temperature of -25° C. to -9° C., the internal temperature was raised to 16° C. over 1 hour, and the mixture was stirred for an additional 3 hours. After cooling to an internal temperature of -20°C, 2M hydrochloric acid (430mL) was added dropwise over 15 minutes at an internal temperature of -20 to -5°C, and then the mixture was returned to room temperature, extracted with ethyl acetate (1L x 2 times), washed with saturated saline (500mL x 2 times), and the oil phase was concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (dichloromethane / hexane = 1 / 4 to 1 / 2) to obtain 52.7g of 2-tert-butyl-4,6-dichloro-1,3,5-triazine as a white solid.

[0293] [ka]

[0294] In a 2L four-necked reactor, 2-bromonaphthalene (55.3 g) and THF (550 mL) were added and dissolved, and the mixture was cooled to an internal temperature of -74°C. Then, 1.6 M n-butyllithium·n-hexane solution (182 mL) was added dropwise at an internal temperature of -74 to -65°C over 35 minutes, and the mixture was stirred for an additional hour. In a separate 3L four-necked reactor, 2-tert-butyl-4,6-dichloro-1,3,5-triazine (50.0 g) was added. 、 After adding THF (500mL) and cooling to an internal temperature of -85°C, the previously prepared lithiation solution was transferred at an internal temperature of -85 to -75°C over 30 minutes. The internal temperature was then raised to 0°C over 2 hours while stirring. Water (600mL) was added, followed by extraction with hexane (600mL x 2 times). The combined oil phase was washed with water (500mL) and saturated saline (500mL), and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (dichloromethane / hexane = 1 / 9 to 1 / 4), yielding 48.4g of 2-tert-butyl-4-chloro-6-(2-naphthyl)-1,3,5-triazine as a white solid.

[0295] [ka]

[0296] In a 1L eggplant flask, 2-bromo-7-iodofluorene (Tokyo Chemical Industry Co., Ltd., 46.3 g), 3-(6-phenyl-n-hexyl)phenylboronic acid (35.5 g), [tetrakis(triphenylphosphine)palladium(0)] (5.4 g), 2M tripotassium phosphate aqueous solution (150 mL), toluene (300 mL) and ethanol (100 mL) were added and stirred under reflux in an oil bath at 105 ° C for 3 hours. After cooling to room temperature, the aqueous phase was removed, and the remaining liquid was concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 15 / 85 to 2 / 8), to obtain 51.3 g of 2-bromo-7-{3-(6-phenyl-n-hexyl)phenyl}fluorene as a white solid.

[0297] [ka]

[0298] 2-Bromo-7-{3-(6-phenyl-n-hexyl)phenyl}fluorene (25.6 g) and dehydrated tetrahydrofuran (380 mL) were placed in a 1 L eggplant flask, and tert-butoxypotassium (13.4 g) was added while cooling in an ice-water bath, and 1-iodo-n-octane (38.3 g) was added dropwise over 15 minutes. The ice-water bath was removed and the mixture was stirred in a 40°C oil bath for 95 minutes. The solvent was distilled off under reduced pressure, and water (150 mL) and ethyl acetate (300 mL) were added for liquid separation and washing. The oil phase was collected and concentrated under reduced pressure, and the resulting residue was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 8 / 2 to 7 / 3), yielding 22.5 g of 2-bromo-7-{3-(6-phenyl-n-hexyl)phenyl}-9,9-di(n-octyl)fluorene as a pale yellow oily substance.

[0299] [ka]

[0300] 2-Bromo-7-{3-(6-phenyl-n-hexyl)phenyl}-9,9-di(n-octyl)fluorene (22.5 g), bis(pinacolato)diboron (9.5 g), potassium acetate (9.3 g), dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium·dichloromethane adduct (0.79 g), and dimethylsulfoxide (200 mL) were placed in a 500 mL recovery flask and stirred at 90° C. for 8 hours. After cooling to room temperature, bis(pinacolato)diboron (4.6 g), potassium acetate (4.8 g), and dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium·dichloromethane adduct (0.79 g) were further added and stirred in an oil bath at 90° C. for another 5 hours. After cooling to room temperature, water (200 mL) and dichloromethane (200 mL) were added for liquid separation and washing. The oil phase was collected and concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 3 / 7) to obtain 19.5 g of 2-[7-{3-(6-phenyl-n-hexyl)phenyl}-9,9-di(n-octyl)fluoren-2-yl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane as a pale yellow oil.

[0301] [ka]

[0302] Into a 1 L recovery flask were added 5-bromo-2-iodopyridine (9.1 g), 2-[9,9-di(n-octyl)-7-{3-(6-phenyl-n-hexyl)phenyl}fluoren-2-yl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (19.5 g), [tetrakis(triphenylphosphine)palladium(0)] (1.5 g), 2 M aqueous tripotassium phosphate solution (31 mL), toluene (80 mL) and ethanol (40 mL), and the mixture was stirred for 7 hours in an oil bath at 105°C. After cooling to room temperature, the aqueous phase was removed, and the remaining liquid was concentrated under reduced pressure to obtain a residue. The residue was purified by silica gel column chromatography (neutral silica gel, ethyl acetate / hexane=1 / 9) to obtain 15.7 g of 9,9-di(n-octyl)-2-{3-(6-phenyl-n-hexyl)phenyl}-7-(5-bromopyridin-2-yl)fluorene as a pale yellow solid.

[0303] [ka]

[0304] 9,9-Di(n-octyl)-2-{3-(6-phenyl-n-hexyl)phenyl}-7-(5-bromopyridin-2-yl)fluorene (15.7 g), bis(pinacolato)diboron (6.0 g), potassium acetate (6.0 g), dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium-dichloromethane adduct (0.50 g), and dimethylsulfoxide (100 mL) were placed in a 1 L eggplant flask and stirred at 90°C for 5 hours. Then, bis(pinacolato)diboron (4.8 g), potassium acetate (3.0 g), and dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium-dichloromethane adduct (0.92 g) were added and stirred at 90°C for 5 hours. After cooling to room temperature, water (200 mL) and dichloromethane (200 mL) were added and washed. The oil phase was collected and concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 3 / 7 to 6 / 4, followed by ethyl acetate / hexane = 1 / 9 to 1 / 0), to obtain 14.1 g of 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2-[9,9-di(n-octyl)-7-{3-(6-phenyl-n-hexyl)phenylfluoren-2-yl}]pyridine as a pale yellow oil.

[0305] [ka]

[0306] In a 1L eggplant flask, 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2-[9,9-di(n-octyl)-7-{3-(6-phenyl-n-hexyl)phenylfluoren-2-yl}]pyridine (8.9 g), 2-tert-butyl-4-chloro-6-β-naphthyl-1,3,5-triazine (3.9 g), [tetrakis(triphenylphosphine)palladium(0)] (0.50 g), 2M tripotassium phosphate aqueous solution (13 mL), toluene (40 mL) and ethanol (20 mL) were added and stirred in an oil bath at 105 ° C for 14 hours. After cooling to room temperature, the aqueous phase was removed, and the remaining liquid was concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 3 / 7 to 1 / 1) to obtain 8.0 g of intermediate 5.

[0307] [ka]

[0308] In a 100 mL recovery flask, intermediate 5 (4.8 g), iridium (III) chloride n-hydrate (0.82 g), 2-ethoxyethanol (40 mL), and water (10 mL) were added, and the mixture was stirred for 6.5 hours while distilling in an oil bath at 135 to 145°C. The amount of liquid distilled and withdrawn was 36 mL. The residue obtained by vacuum concentration was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 3 / 7 to 1 / 1), and 4.1 g of intermediate 6 was obtained as a red solid.

[0309] [ka]

[0310] In a 100 mL eggplant flask, add intermediate 6 (4.1 g), intermediate 5 (3.6 g), silver(I) trifluoromethanesulfonate (0.50 g), and diglyme (14 mL) were added and stirred for 8 hours in an oil bath at 145° C. The residue obtained by concentration under reduced pressure was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane=2 / 8) to obtain 5.2 g of compound D-3 as a red solid.

[0311] <Synthesis Example 4: Synthesis of Compound D-4>

[0312] [ka]

[0313] In a 2L four-necked reactor, 3-bromo-3'-(6-phenyl-n-hexyl)-1,1'-biphenyl (38.2 g, synthesized by the method described in WO 2016 / 194784) and THF (380 mL) were added and dissolved, then cooled to an internal temperature of -76°C, and 1.6M n-butyllithium·n-hexane solution (64 mL) was added dropwise at an internal temperature of -76 to -66°C over 30 minutes, and further stirred for 1 hour. In another 2L four-necked reactor, 2-tert-butyl-4,6-dichloro-1,3,5-triazine (20.0 g) and THF (300 mL) were added and cooled to an internal temperature of -85°C, and the previously prepared lithiated solution was transferred at an internal temperature of -85 to -80°C over 20 minutes. The internal temperature was further increased to 6°C over 2 hours with stirring. After adding water (300 mL) dropwise, the mixture was extracted with ethyl acetate (350 mL x 2 times), and the combined oil phase was washed successively with water (200 mL) and saturated saline (100 mL). The residue obtained by concentrating under reduced pressure was purified by silica gel column chromatography (dichloromethane / hexane = 1 / 4 to 1 / 2) to obtain 17.9 g of 2-tert-butyl-4-chloro-6-{3'-(6-phenyl-n-hexyl)-1,1'-biphenyl-3-yl}-1,3,5-triazine as a colorless oily substance.

[0314] [ka]

[0315] 9-Bromo-7,7-dimethyl-7H-benzo[c]fluorene (Tokyo Chemical Industry Co., Ltd., 7.3 g), bis(pinacolato)diboron (6.6 g), potassium acetate (6.7 g), dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium·dichloromethane adduct (0.60 g) and dimethylsulfoxide (55 mL) were placed in a 100 mL recovery flask and stirred at 90°C for 3 hours. After that, it was cooled to room temperature and water (300 mL) and dichloromethane (200 mL) were added for separation and washing. The oil phase was collected, dried over magnesium sulfate, and then concentrated under reduced pressure to obtain a residue. The residue was purified by silica gel column chromatography (neutral silica gel, ethyl acetate / hexane=15 / 85) to obtain 7.4 g of 2-(7,7-dimethyl-7H-benzo[c]fluoren-9-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane as a white amorphous solid.

[0316] [ka]

[0317] In a 1L eggplant flask, 2-(7,7-dimethyl-7H-benzo[c]fluoren-9-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (7.4 g), 5-bromo-2-iodopyridine (6.3 g), [tetrakis(triphenylphosphine)palladium(0)] (0.80 g), 2M tripotassium phosphate aqueous solution (30 mL), toluene (40 mL) and ethanol (20 mL) were added and stirred in an oil bath at 105 ° C for 17 hours. After cooling to room temperature, the aqueous phase was removed, and the remaining liquid was concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 3 / 7), to obtain 7.9 g of 5-bromo-2-(7,7-dimethyl-7H-benzo[c]fluoren-9-yl)pyridine as a white solid.

[0318] [ka]

[0319] In a 1L eggplant flask, 5-bromo-2-(7,7-dimethyl-7H-benzo[c]fluoren-9-yl)pyridine (7.9g), bis(pinacolato)diboron (5.9g), potassium acetate (6.8g), dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium-dichloromethane adduct (0.74g) and dimethylsulfoxide (90mL) were placed and stirred in an oil bath at 90°C for 10 hours. After cooling to room temperature, bis(pinacolato)diboron (1.2g) and dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium-dichloromethane adduct (0.22g) were added and stirred again at 90°C for 5.5 hours. After cooling to room temperature, water (300mL) and dichloromethane (100mL) were added for liquid separation and washing. The oil phase was collected and concentrated under reduced pressure to obtain a residue, which was then purified by silica gel column chromatography (neutral silica gel, ethyl acetate / hexane = 1 / 4 to 4 / 6) to obtain 2.8 g of 2-(7,7-dimethyl-7H-benzo[c]fluoren-9-yl)-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine as a brown oil.

[0320] [ka]

[0321] In a 1L eggplant flask, 2-(7,7-dimethyl-7H-benzo[c]fluoren-9-yl)-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine (2.8 g), 2-tert-butyl-4-chloro-6-{3'-(6-phenyl-n-hexyl)-1,1'-biphenyl-3-yl}-1,3,5-triazine (5.0 g), [tetrakis(triphenylphosphine)palladium(0)] (0.45 g), 2M tripotassium phosphate aqueous solution (15 mL), toluene (30 mL) and ethanol (30 mL) were added and stirred in an oil bath at 105 ° C. for 4 hours. After cooling to room temperature, the aqueous phase was removed, and the remaining liquid was concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 1 / 1) to obtain 2.8 g of intermediate 7 as a yellow amorphous solid.

[0322] [ka]

[0323] In a 100 mL recovery flask, intermediate 7 (1.5 g), iridium (III) chloride n-hydrate (0.34 g), 2-ethoxyethanol (26 mL), and water (6 mL) were added, and the mixture was stirred for 10 hours while distilling in an oil bath at 135 to 145 ° C. After 3.5 hours, 20 mL of 2-ethoxyethanol was added. The final amount of liquid distilled and extracted was 30 mL. After the reaction was completed, the residue obtained by vacuum concentration was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 1 / 1), and 1.53 g of intermediate 8 was obtained as a red solid.

[0324] [ka]

[0325] In a 100 mL recovery flask, intermediate 8 (1.5 g), intermediate 7 (1.2 g), silver(I) trifluoromethanesulfonate (0.28 g), and diglyme (5 mL) were added and stirred for 2.5 hours in an oil bath at 145° C. The residue obtained by vacuum concentration was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane=2 / 8), yielding 1.4 g of compound D-4 as a red solid.

[0326] <Synthesis Example 5: Synthesis of Compound D-5>

[0327] [ka]

[0328] 2-Bromo-7-iodofluorene (Tokyo Chemical Industry Co., Ltd., 26.2 g), 2-naphthylboronic acid (12.7 g), [tetrakis(triphenylphosphine)palladium(0)] (1.4 g), 2M tripotassium phosphate aqueous solution (95 mL), toluene (100 mL) and ethanol (40 mL) were added to a 1L eggplant flask, and the mixture was stirred under reflux for 5.5 hours in an oil bath at 105° C. After cooling to room temperature, the aqueous phase was removed, methanol (200 mL) was added to the remaining liquid, and the precipitated solid was filtered, washed by spraying methanol (100 mL), and dried to obtain 24.3 g of 2-bromo-7-(2-naphthyl)fluorene as a white solid.

[0329] [ka]

[0330] In a 300 mL eggplant flask, 2-bromo-7-(2-naphthyl)fluorene (9.4 g), 1-iodo-n-octane (15 mL) and dehydrated tetrahydrofuran (65 mL) were placed, and potassium tert-butoxide (8.6 g) was added while cooling in an ice-water bath. The ice-water bath was then removed and the mixture was stirred for 5 hours in an oil bath at 40° C. The solvent was distilled off under reduced pressure, and the resulting residue was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane=15 / 85), yielding 12.9 g of 2-bromo-7-(2-naphthyl)-9,9-di(n-octyl)fluorene as a yellow-green solid.

[0331] [ka]

[0332] 2-Bromo-7-(2-naphthyl)-9,9-di(n-octyl)fluorene (12.9 g), bis(pinacolato)diboron (7.0 g), potassium acetate (6.5 g), dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium·dichloromethane adduct (0.67 g), and dimethylsulfoxide (80 mL) were placed in a 1 L eggplant flask and stirred for 2.5 hours in an oil bath at 90 °C. 1,4-Dioxane (20 mL) was added and stirred for an additional hour. Bis(pinacolato)diboron (3.5 g), potassium acetate (3.6 g), and dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium·dichloromethane adduct (0.27 g) were added and stirred for an additional 3.5 hours. After cooling to room temperature, water (200 mL) and dichloromethane (100 mL x 3) were added and the mixture was separated and extracted. The oil phase was collected and concentrated under reduced pressure, and the resulting residue was purified by silica gel column chromatography (neutral silica gel, ethyl acetate / hexane = 1 / 4 to 4 / 6), yielding 7.4 g of 7-(2-naphthyl)-9,9-di(n-octyl)-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)fluorene as a pale yellow oil.

[0333] [ka]

[0334] In a 1L eggplant flask, 7-(2-naphthyl)-9,9-di(n-octyl)-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)fluorene (7.4 g), 5-bromo-2-iodopyridine (3.9 g), [tetrakis(triphenylphosphine)palladium(0)] (0.70 g), 2M tripotassium phosphate aqueous solution (14 mL), toluene (30 mL) and ethanol (15 mL) were added and stirred in an oil bath at 105 ° C. for 8 hours. After cooling to room temperature, the aqueous phase was removed, and the remaining liquid was concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, the product obtained with ethyl acetate / hexane = 1 / 9 was further purified with dichloromethane / hexane = 4 / 6), and 6.4 g of 5-bromo-2-(7-naphthyl-9,9-di(n-octyl)fluoren-2-yl)pyridine was obtained.

[0335] [ka]

[0336] In a 500 mL eggplant flask, 5-bromo-2-(7-naphthyl-9,9-di(n-octyl)fluoren-2-yl)pyridine (6.3 g), bis(pinacolato)diboron (2.8 g), potassium acetate (2.8 g), dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium·dichloromethane adduct (0.24 g) and dimethylsulfoxide (45 mL) were placed and stirred for 4.5 hours in an oil bath at 90°C. After cooling to room temperature, bis(pinacolato)diboron (1.4 g), potassium acetate (1.5 g) and dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium·dichloromethane adduct (0.15 g) were added and stirred again at 90°C for 4.5 hours. After cooling to room temperature, water (200 mL) and dichloromethane (200 mL) were added and washed. The oil phase was collected and concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, ethyl acetate / hexane = 1 / 9 to 1 / 1) to obtain 6.4 g of 2-(7-naphthyl-9,9-di(n-octyl)fluoren-2-yl)-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine as a brown oil.

[0337] [ka]

[0338] In a 1 L eggplant flask, 2-(7-naphthyl-9,9-di(n-octyl)fluoren-2-yl)-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine (6.2 g), 2-tert-butyl-4-chloro-6-{3'-(6-phenyl-n-hexyl)-1,1'-biphenyl-3-yl}-1,3,5-triazine (5.0 g), [tetrakis(triphenylphosphine)palladium(0)] (0.41 g), 2M tripotassium phosphate aqueous solution (11 mL), toluene (36 mL) and ethanol (18 mL) were added and stirred for 9 hours in a 105°C oil bath. After cooling to room temperature, the aqueous phase was removed, and the remaining liquid was concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 3 / 7 to 4 / 6) to obtain 5.9 g of intermediate 9 as a yellow amorphous solid.

[0339] [ka]

[0340] In a 100 mL recovery flask, intermediate 9 (5.6 g), iridium (III) chloride n-hydrate (0.94 g), 2-ethoxyethanol (50 mL), and water (12 mL) were added, and the mixture was stirred for 5.5 hours while distilling in an oil bath at 135 to 150 °C. The final amount of liquid distilled and withdrawn was 47 mL. After the reaction was completed, the residue obtained by vacuum concentration was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 4 / 6 to 1 / 1), and 4.9 g of intermediate 10 was obtained as a red solid.

[0341] [ka]

[0342] Intermediate 10 (4.9 g), Intermediate 9 (3.6 g), silver(I) trifluoromethanesulfonate (0.59 g), and diglyme (16 mL) were added to a 100 mL recovery flask, and the mixture was stirred for 5.5 hours in an oil bath at 145° C. The residue obtained by vacuum concentration was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane=4 / 6), yielding 4.4 g of compound D-5 as a red solid.

[0343] <Synthesis Example 6: Synthesis of Compound D-6>

[0344] [ka]

[0345] In a 300 mL eggplant flask, 2-bromo-7-(2-naphthyl)fluorene (9.4 g), iodomethane (7.5 mL) and dehydrated tetrahydrofuran (100 mL) were placed, and while cooling in an ice-water bath, potassium tert-butoxide (13.2 g) was added, after which the ice-water bath was removed and the mixture was stirred in an oil bath at 40° C. for 3 hours. The solvent was distilled off under reduced pressure, and the resulting residue was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 15 / 85 to 25 / 75), yielding 11.9 g of 2-bromo-9,9-dimethyl-7-(2-naphthyl)-fluorene as a white solid.

[0346] [ka]

[0347] 2-Bromo-9,9-dimethyl-7-(2-naphthyl)-fluorene (11.9 g), bis(pinacolato)diboron (8.9 g), potassium acetate (9.4 g), dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium·dichloromethane adduct (1.0 g) and dimethylsulfoxide (60 mL) were placed in a 1 L eggplant flask and stirred for 4 hours in an oil bath at 90°C. After cooling to room temperature, water (500 mL) and dichloromethane (300 mL) were added for liquid separation and extraction. The oil phase was collected and concentrated under reduced pressure to obtain a residue, which was then purified by silica gel column chromatography (neutral silica gel, ethyl acetate / hexane=2 / 8) to obtain 11.1 g of 9,9-dimethyl-7-(2-naphthyl)-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)fluorene as a white solid.

[0348] [ka]

[0349] In a 1-L eggplant flask, 9,9-dimethyl-7-(2-naphthyl)-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)fluorene (11.1 g), 5-bromo-2-iodopyridine (8.1 g), [tetrakis(triphenylphosphine)palladium(0)] (1.2 g), and 2 M aqueous potassium phosphate solution (35 m L), toluene (60 mL) and ethanol (35 mL) were added and stirred for 8.5 hours in an oil bath at 105° C. After cooling to room temperature, the aqueous phase was removed and the remaining liquid was filtered to obtain a solid, which was washed with ethanol (200 mL) and then dried to obtain 8.5 g of 5-bromo-2-(9,9-dimethyl-7-naphthylfluoren-2-yl)pyridine.

[0350] [ka]

[0351] In a 500 mL eggplant flask, add 5-bromo-2-(9,9-dimethyl-7-naphthylfluoren-2-yl) Pyridine (8.5 g), bis(pinacolato)diboron (6.1 g), potassium acetate (6.3 g), dichloro(1,1'-bis(diphenylphosphino)ferrocene)palladium·dichloromethane adduct (0.61 g), dimethylsulfoxide (70 mL) and 1,4-dioxane (25 mL) were added and stirred in an oil bath at 90°C for 4 hours. After 2 hours, 1,4-dioxane (30 mL) was added. After cooling to room temperature, water (500 mL) and dichloromethane (300 mL) were added for liquid separation and washing. The oil phase was collected and concentrated under reduced pressure to obtain a residue, which was then purified by silica gel column chromatography (neutral silica gel, dichloromethane / tetrahydrofuran = 1 / 0 to 8 / 2) to obtain 6.4 g of 2-(9,9-dimethyl-7-naphthylfluoren-2-yl)-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine as a beige solid.

[0352] [ka]

[0353] In a 1 L eggplant flask, 2-(9,9-dimethyl-7-naphthylfluoren-2-yl)-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine (6.4 g), 2-tert-butyl-4-chloro-6-{3'-(6-phenyl-n-hexyl)-1,1'-biphenyl-3-yl}-1,3,5-triazine (5.9 g), [tetrakis(triphenylphosphine)palladium(0)] (0.52 g), 2M tripotassium phosphate aqueous solution (20 mL), toluene (40 mL) and ethanol (15 mL) were added and stirred for 5 hours in a 105°C oil bath. After cooling to room temperature, the aqueous phase was removed, and the remaining liquid was concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 3 / 7 to 6 / 4) to obtain 7.1 g of intermediate 11 as a yellow-green amorphous solid.

[0354] [ka]

[0355] In a 100 mL recovery flask, intermediate 11 (5.1 g), iridium (III) chloride n-hydrate (1.0 g), 2-ethoxyethanol (60 mL), and water (10 mL) were added, and the mixture was stirred for 7 hours while distilling in an oil bath at 140 to 150 °C. 2-ethoxyethanol (16 mL) was added 1.5 hours later. The final amount of the liquid distilled and withdrawn was about 50 mL. After the reaction was completed, the residue obtained by vacuum concentration was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 1 / 1), and 5.0 g of intermediate 12 was obtained as a red solid.

[0356] [ka]

[0357] In a 100 mL recovery flask, intermediate 12 (5.0 g), intermediate 11 (2.0 g), silver (I) trifluoromethanesulfonate (0.77 g), and diglyme (12 mL) were added, and the mixture was stirred for 1.5 hours in an oil bath at 145° C., and then stirred for 2 hours at 150° C. The residue obtained by vacuum concentration was purified by silica gel column chromatography (neutral silica gel, toluene / hexane = 1 / 1 to 2 / 1), and 2.7 g of compound D-6 was obtained as a red solid.

[0358] <Synthesis Example 7: Synthesis of Compound D-7>

[0359] [ka]

[0360] 2-(4-biphenylyl)-4,6-dichloro-1,3,5-triazine (10.0 g, Tokyo Chemical Industry Co., Ltd.), copper(I) iodide (0.21 g) and dehydrated tetrahydrofuran (100 mL) were placed in a 300 mL four-neck flask, and a 2M-THF (tetrahydrofuran) solution of tert-butylmagnesium bromide (Tokyo Chemical Industry Co., Ltd., 18.5 mL) was added dropwise at an internal temperature of -63° C., and the mixture was stirred for 2.5 hours while heating to -10° C. 1N-hydrochloric acid (120 mL) was added, followed by extraction with ethyl acetate (200 mL) and washing the oil phase with brine (200 mL). After the solvent in the oil phase was removed under reduced pressure, the residue was purified by silica gel column chromatography (dichloromethane / hexane=35 / 65) to obtain 6.8 g of the desired 2-(4-biphenylyl)-4-tert-butyl-6-chloro-1,3,5-triazine.

[0361] [ka]

[0362] In a 1L eggplant flask, [2-{9,9-di(n-octyl)fluoren-2-yl}pyridin-5-yl]4,4,5,5-tetramethyl-1,3,2-dioxaborolane (12.2g), 2-(4-biphenylyl)-4-tert-butyl-6-chloro-1,3,5-triazine (7.7g), tetrakis(triphenylphosphine)palladium(0)] (1.0g), 2M-tripotassium phosphate aqueous solution (30mL), toluene (75mL) and ethanol (50mL) were added and stirred for 9.5 hours in an oil bath at 105°C. After cooling to room temperature, the aqueous phase was removed, and the remaining liquid was concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 4 / 6), to obtain 14.5g of intermediate 13 as a colorless amorphous substance.

[0363] [ka]

[0364] In a 300 mL recovery flask, intermediate 13 (9.4 g), iridium (III) chloride n-hydrate (2.06 g), 2-ethoxyethanol (90 mL), and water (21 mL) were added, and the temperature of the oil bath was raised to 135-150°C while distilling, and the mixture was stirred for 13 hours. The residue obtained by vacuum concentration was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 6 / 4), and 9.6 g of intermediate 14 was obtained as a red solid.

[0365] [ka]

[0366] In a 1 L recovery flask, intermediate 14 (9.6 g), intermediate 13 (5.1 g), silver(I) trifluoromethanesulfonate (1.5 g), and diglyme (32 mL) were added and stirred for 4.5 hours in an oil bath at 145° C. The residue obtained by vacuum concentration was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane=1 / 1), obtaining 2.7 g of compound D-7 as a red solid.

[0367] <Synthesis Example 8: Synthesis of Compound D-8>

[0368] [ka]

[0369] In a 2L four-necked reactor, magnesium turnings (26.5 g) and diethyl ether (180 mL) were placed, and 2 mL of 1-chloro-2,2-dimethylpropane (84.9 g) was added. After initiating the reaction by adding 1,2-dibromoethane (450 μL), the remaining 1-chloro-2,2-dimethylpropane in diethyl ether (430 mL) was added dropwise over 3 hours and 40 minutes at an internal temperature of 30 to 40°C, and the mixture was refluxed and stirred for another 2 hours, after which it was cooled to room temperature. In a separate 3L four-necked reactor, 2,4-dichloro-6-phenyl-1,3,5-triazine (120.0 g) and THF (900 mL) were added. of After the solution was added, copper iodide (I) (3.0 g) was added and cooled to an internal temperature of -23°C. Next, the Grignard reagent solution prepared above was added dropwise over 25 minutes at an internal temperature of -23 to -4°C, and the temperature was raised to 20°C over 1 hour. After cooling the internal temperature to -20°C again, 2M-hydrochloric acid (800 mL) was added dropwise over 10 minutes so that the internal temperature was within -20 to 0°C, and then the mixture was stirred for 15 minutes while returning to room temperature. The mixture was extracted with ethyl acetate (500 mL x 2), washed with a mixture of water (250 ml) and saturated saline (250 mL), and the oil phase was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (dichloromethane / hexane = 1 / 9 to 1 / 5), and 62.4 g of 2-chloro-4-neopentyl-6-phenyl-1,3,5-triazine was obtained as a white solid.

[0370] [ka]

[0371] In a 1L eggplant flask, 2-(7-ethyl-9,9-di(n-octyl)fluoren-2-yl)-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine (6.9 g), 2-chloro-4-neopentyl-6-phenyl-1,3,5-triazine (4.0 g), [tetrakis(triphenylphosphine)palladium(0)] (0.68 g), 2M tripotassium phosphate aqueous solution (20 mL), toluene (40 mL) and ethanol (20 mL) were added and stirred in an oil bath at 105 ° C. for 3 hours. After cooling to room temperature, the aqueous phase was removed, and the remaining liquid was concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, ethyl acetate / hexane = 15 / 85) to obtain 6.6 g of intermediate 15 as a white solid.

[0372] [ka]

[0373] In a 300 mL recovery flask, intermediate 15 (4.2 g), iridium(III) chloride n-hydrate (0.97 g), 2-ethoxyethanol (40 mL), and water (10 mL) were added, and the temperature of the oil bath was raised to 140-170°C while distilling, and the mixture was stirred for 16 hours. The residue obtained by vacuum concentration was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 6 / 4), and the intermediate 15 was obtained as a red solid. 16 9.6g was obtained.

[0374] [ka]

[0375] In a 1L recovery flask, intermediate 16 (1.4 g), intermediate 15 (2.4 g), silver(I) trifluoromethanesulfonate (0.22 g), and diglyme (3 mL) were added and stirred for 2 hours in an oil bath at 145°C. The residue obtained by vacuum concentration was analyzed by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 2 / 8 ~ 1 / 1) to obtain 1.7 g of compound D-8 as a red solid.

[0376] <Synthesis Example 9: Synthesis of Compound D-9>

[0377] [ka]

[0378] In a 1L eggplant flask, 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2-[9,9-di(n-octyl)fluoren-2-yl]pyridine (37.2 g), 2-tert-butyl-4-chloro-6-phenyl-1,3,5-triazine (18.7 g), [tetrakis(triphenylphosphine)palladium(0)] (2.9 g), 2M tripotassium phosphate aqueous solution (78 mL), toluene (200 mL) and tetrahydrofuran (100 mL) were added and stirred for 5 hours in an oil bath at 105 ° C. After cooling to room temperature, the aqueous phase was removed, and the remaining liquid was concentrated under reduced pressure to obtain a residue, which was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 1 / 1) to obtain 29.1 g of intermediate 17 as a yellow oil.

[0379] [ka]

[0380] In a 300 mL recovery flask, intermediate 17 (16.4 g), iridium (III) chloride n-hydrate (4.0 g), 2-ethoxyethanol (140 mL), and water (33 mL) were added, and the temperature of the oil bath was raised to 135-140°C while distilling, and the mixture was stirred for 6.5 hours. The residue obtained by vacuum concentration was then purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane = 6 / 4), and 17.4 g of intermediate 18 was obtained as a red solid.

[0381] [ka]

[0382] In a 1L recovery flask, intermediate 18 (17.4 g), intermediate 17 (6.5 g), silver(I) trifluoromethanesulfonate (2.8 g), and diglyme (58 mL) were added and stirred for 5 hours in an oil bath at 145° C. The residue obtained by vacuum concentration was purified by silica gel column chromatography (neutral silica gel, dichloromethane / hexane=2 / 8), obtaining 10.3 g of compound D-9 as a red solid.

[0383] <Comparative compound D-C1> According to the method described in Patent Document 1, a comparative compound D-C1 shown in the following formula was synthesized.

[0384] [ka]

[0385] <Comparative compound D-C2> Comparative compound D-C2 shown in the following formula was synthesized according to the method described in Patent Document 3 and the method described in the synthesis example of compound D-2.

[0386] [ka]

[0387] [Measurement of maximum emission wavelength and half-width] Compound 1 was dissolved in 2-methyltetrahydrofuran (manufactured by Aldrich, dehydrated, no stabilizer added) at room temperature and diluted to 1 × 10 -5 A solution of 1.0 mol / L was prepared. This solution was placed in a quartz cell equipped with a Teflon (registered trademark) cock, and after nitrogen bubbling for 20 minutes or more, the phosphorescence spectrum was measured at room temperature. The wavelength showing the maximum intensity of the obtained phosphorescence spectrum was taken as the maximum emission wavelength. The width of the spectrum intensity at half the maximum emission wavelength was taken as the half-width. cm -1 The half-width expressed in nm is calculated by reading the shorter wavelength exceeding a height of 0.5 and the longer wavelength below a height of 0.5 from the spectrum data normalized to a converted height of 1, and converting nm to cm -1 Convert the difference to cm -1 The half-width of the

[0388] The following equipment was used to measure the emission spectrum. Equipment: Hamamatsu Photonics Organic EL quantum yield measurement equipment C9920-02 Light source: Monochrome light source L9799-01 Detector: Multichannel detector PMA-11 Excitation light: 380 nm

[0389] [PL quantum yield measurement] The PL quantum yield was measured as the luminous efficiency. The PL quantum yield is an index showing the efficiency of luminescence with respect to the light (energy) absorbed by a material, and was measured using the following equipment as above. Apparatus: Hamamatsu Photonics Organic EL Quantum Yield Measurement Apparatus C9920-02 Light Source: Monochrome Light Source L9799-01 Detector: Multichannel Detector PMA-11 Excitation Light: 380 nm For Comparative Compound 1, the half width, maximum wavelength and PL quantum yield were similarly measured.

[0390] [Table 1]

[0391] From the above, it is clearly understood that the compound D-1 has a particularly narrow half-width compared to the comparative compound D-C1.

[0392] [Measurement of maximum emission wavelength and half-width 2] Compound D-1 was dissolved in toluene (Fujifilm Wako Pure Chemical Industries, Ltd., for spectroscopic analysis) at room temperature and diluted to 1 × 10 -5 A solution of 1.0 mol / L was prepared. This solution was placed in a quartz cell equipped with a Teflon (registered trademark) cock, and after nitrogen bubbling for 20 minutes or more, the phosphorescence spectrum was measured at room temperature. The wavelength showing the maximum intensity of the obtained phosphorescence spectrum was taken as the maximum emission wavelength. The width of the spectrum intensity at half the maximum emission wavelength was taken as the half-width. cm -1 The half-width expressed in nm is calculated by reading the shorter wavelength exceeding a height of 0.5 and the longer wavelength below a height of 0.5 from the spectrum data normalized to a converted height of 1, and converting nm to cm -1 Convert the difference to cm -1 The half-width of the

[0393] The following equipment was used to measure the emission spectrum. Equipment: Hamamatsu Photonics Organic EL quantum yield measurement equipment C9920-02 Light source: Monochrome light source L9799-01 Detector: Multichannel detector PMA-11 Excitation light: 380 nm

[0394] [PL quantum yield measurement] The PL quantum yield was measured as the luminous efficiency. The PL quantum yield is an index showing the efficiency of luminescence with respect to the light (energy) absorbed by a material, and was measured using the following equipment as above. Equipment: Hamamatsu Photonics Organic EL quantum yield measurement equipment C9920-02 Light source: Monochrome light source L9799-01 Detector: Multichannel detector PMA-11 Excitation light: 380 nm

[0395] Similarly, the half-width, maximum wavelength, and PL quantum yield were measured for compounds D-1, D-3 to D-5, D-8, and D-9, as well as comparative compounds D-C1 and D-C2.

[0396] [Table 2]

[0397] The PL quantum yield values ​​are considered to be almost the same except for compound D-4. Compound D-4 has a longer wavelength than the others, and is therefore considered to have shown a slightly lower quantum yield value due to the so-called energy gap law. It was found that the half-width values ​​of compounds D-1, D-3 to D-5, D-8, and D-9 were all equal to or narrower than that of comparative compound D-C1, and significantly narrower than that of comparative compound D-C2.

[0398] [Example 1] An organic electroluminescent device was fabricated in the following manner. A 50 nm thick indium tin oxide (ITO) transparent conductive film (Geomatec, sputtered film) was deposited on a glass substrate and patterned into 2 mm wide stripes using standard photolithography and hydrochloric acid etching to form the anode. The substrate with the ITO pattern formed in this way was ultrasonically cleaned with a surfactant solution, rinsed with ultrapure water, ultrasonically cleaned with ultrapure water, and rinsed with ultrapure water, in that order, then dried with compressed air and finally cleaned with ultraviolet ozone. As a composition for forming a hole injection layer, a composition was prepared by dissolving 3.0 wt % of a hole transporting polymer compound having a repeating structure of the following formula (P-1) and 0.6 wt % of an oxidizing agent (HI-1) in ethyl benzoate.

[0399] [ka]

[0400] This solution was spin-coated onto the substrate in the atmosphere and dried on a hot plate in the atmosphere at 240° C. for 30 minutes to form a uniform thin film with a thickness of 39 nm, which was used as a hole injection layer. Next, 100 parts by mass of a charge transporting polymer compound having the following structural formula (HT-1) was dissolved in cyclohexylbenzene to prepare a 3.0% by weight solution. This solution was spin-coated in a nitrogen glove box onto the substrate on which the hole injection layer had been formed, and then dried on a hot plate in the nitrogen glove box at 230°C for 30 minutes to form a uniform thin film with a thickness of 42 nm, which served as a hole transport layer.

[0401] [ka]

[0402] Next, as materials for the light-emitting layer, 50 parts by mass of the following structural formula (H-1), 50 parts by mass of the following structural formula (H-2), 15 parts by mass of the following structural formula (D-A1), and 15 parts by mass of the following structural formula (D-2) were each weighed out and dissolved in cyclohexylbenzene to prepare a 5.0 wt % solution.

[0403] [ka]

[0404] This solution was spin-coated in a nitrogen glove box onto the substrate on which the hole transport layer had been formed, and dried on a hot plate in the nitrogen glove box at 120°C for 20 minutes to form a uniform thin film with a thickness of 60 nm, which was used as the light-emitting layer. The substrate on which the light-emitting layer had been formed was placed in a vacuum deposition apparatus, and the inside of the apparatus was heated to 2 × 10 -4 The pressure was evacuated until the pressure was below 1 Pa. Next, the following structural formula (ET-1) and 8-hydroxyquinolinolatolithium were co-deposited on the light-emitting layer in a thickness ratio of 2:3 by vacuum deposition to form a hole blocking layer with a thickness of 30 nm.

[0405] [ka]

[0406] Next, a 2 mm wide striped shadow mask was attached to the substrate as a mask for cathode deposition so as to be perpendicular to the ITO stripes of the anode, and aluminum was heated in a molybdenum boat to form an aluminum layer with a thickness of 80 nm to form a cathode. In this manner, an organic electroluminescent device having a light-emitting area of ​​2 mm x 2 mm was obtained.

[0407] (Element evaluation) The obtained organic electroluminescent device was energized to emit light, and the peak wavelength and half-width of the emission spectrum were measured. In addition, this element is 1000cd / m 2 The external quantum efficiency (EQE (%)) was calculated when the device was made to emit light at a brightness of 100 nm. Furthermore, to evaluate the operating life of the element, a current of 60 mA / cm was applied to this element. 2 A current density of 1000 mA was continuously applied to each of the elements, and the time (LT95 (hr)) until the luminance of the element decreased to 95% of the initial luminance was measured. The LT95 lifespans of Examples 1 to 5 are shown in Table 4 as relative lifespans when the LT95 of Comparative Example 1 is taken as 1.

[0408] [Example 2] An organic electroluminescent device was produced in the same manner as in Example 1, except that the composition of the light-emitting layer was changed to the following structural formula (D-3) instead of the above structural formula (D-2).

[0409] [ka]

[0410] [Example 3] An organic electroluminescent device was produced in the same manner as in Example 1, except that the composition of the light-emitting layer was changed to the following structural formula (D-4) instead of the above structural formula (D-2).

[0411] [ka]

[0412] [Example 4] An organic electroluminescent device was produced in the same manner as in Example 1, except that the composition of the light-emitting layer was changed to the following structural formula (D-5) instead of the above structural formula (D-2).

[0413] [ka]

[0414] [Example 5] An organic electroluminescent device was produced in the same manner as in Example 1, except that the composition of the light-emitting layer was changed to the following structural formula (D-6) instead of the above structural formula (D-2).

[0415] [ka]

[0416] [Example 6] An organic electroluminescence device was produced in the same manner as in Example 1, except that the composition of the light-emitting layer was changed to the following structural formula (D-7) instead of the above structural formula (D-2).

[0417] [ka]

[0418] [Comparative Example 1] An organic electroluminescent device was produced in the same manner as in Example 1, except that the composition of the light-emitting layer was changed to the following structural formula (D-C1) instead of the above structural formula (D-2).

[0419] [ka]

[0420] [Solution spectrum] The maximum emission wavelength was determined from the solution spectrum of each light-emitting material. The compound was dissolved in toluene at room temperature at a concentration of 1×10 -5 A solution was prepared by dissolving the compound in mol / L, and after bubbling with nitrogen for 20 minutes or more, the photoluminescence spectrum was measured using a spectrophotometer (Organic EL quantum yield measurement device C9920-02 manufactured by Hamamatsu Photonics KK). The wavelength showing the maximum value of the obtained spectrum intensity was taken as the maximum emission wavelength and is shown in Table 3.

[0421] [Table 3]

[0422] [Element evaluation] From the results in Table 4, in the organic electroluminescent device according to this embodiment, the luminous efficiency was equivalent to that of the conventional device, and the half-value width was narrow and favorable. Moreover, the elements using the light-emitting materials including the organic electroluminescent element according to this embodiment had a long and favorable operating life.

[0423] [Table 4]

[0424] [Comparative Example 2] An organic electroluminescent device was produced in the same manner as in Example 1, except that the composition of the light-emitting layer was changed to the following structural formula (D-C2) instead of the above structural formula (D-2).

[0425] [ka]

[0426] When this element was caused to emit light, the peak wavelength and half-width of the emission spectrum were 617 nm and 61 nm, respectively, and the half-width was unsatisfactory because it was wide.

[0427] It was confirmed that the iridium complex compound represented by formula (1) can narrow the half-width. It was also confirmed that the half-width was narrowed and the lifetime was improved in structural formulas (D-2), (D-3), (D-5), and (D-6) in which fluorene has a substituent, and in structural formula (D-4) in which fluorene is condensed.

[0428] Although the present invention has been described in detail and with reference to specific embodiments, it is apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention. This application is based on a Japanese patent application (Patent Application No. 2020-021319) filed on February 12, 2020, the contents of which are incorporated herein by reference. [Explanation of symbols]

[0429] REFERENCE SIGNS LIST 1 substrate 2 anode 3 hole injection layer 4 hole transport layer 5 light emitting layer 6 hole blocking layer 7 electron transport layer 8 electron injection layer 9 cathode 10 organic electroluminescent device< / w>

Claims

1. An iridium complex compound represented by the following formula (1): 【Chemistry 1】 In formula (1), Ir represents an iridium atom. ５ ~R １４ , R ２１ and R ２２ each independently represents a hydrogen atom, D, F, Cl, Br, I, -N(R')2, -CN, -NO2, -OH, -COOR', -C(=O)R', -C(=O)NR', ​​-P(=O)(R')2, -S(=O)R', -S(=O)2R', -OS(=O)2R', a linear or branched alkyl group having 1 to 30 carbon atoms, a cyclic alkyl group having 3 to 30 carbon atoms, a linear or branched alkoxy group having 1 to 30 carbon atoms, a cyclic alkoxy group having 2 to 30 carbon atoms, a linear or branched alkylthio group having 1 to 30 carbon atoms, a cyclic alkylthio group having 2 to 30 carbon atoms, a linear or branched alkenyl group having 2 to 30 carbon atoms, a cyclic alkenyl group having 3 to 30 carbon atoms, or a linear or branched alkynyl group having 2 to 30 carbon atoms. , a cyclic alkynyl group having 3 to 30 carbon atoms, an aromatic group having 5 to 60 carbon atoms, a heteroaromatic group having 1 to 60 carbon atoms, an aryloxy group having 5 to 40 carbon atoms, an arylthio group having 5 to 40 carbon atoms, an aralkyl group having 5 to 60 carbon atoms, a heteroaralkyl group having 2 to 60 carbon atoms, a diarylamino group having 10 to 40 carbon atoms, an arylheteroarylamino group having 10 to 40 carbon atoms, or a diheteroarylamino group having 10 to 40 carbon atoms. In the alkyl group, alkoxy group, alkylthio group, alkenyl group and alkynyl group, at least one or more hydrogen atoms may be further substituted with R' (excluding hydrogen atoms), and one -CH 2 - group or two or more non-adjacent -CH 2 - groups in these groups may be substituted with -C(-R')=C(-R')-, -C≡C-, -Si(-R') 2 , -C(=O)-, -NR'-, -O-, -S-, -CONR'- or a divalent aromatic group. Also, one or more hydrogen atoms in these groups may be substituted with D, F, Cl, Br, I or -CN. In the aromatic group, the heteroaromatic group, the aryloxy group, the arylthio group, the aralkyl group, the heteroaralkyl group, the diarylamino group, the arylheteroarylamino group and the diheteroarylamino group, at least one hydrogen atom may be further substituted with R' (excluding hydrogen atoms). R' each independently represents a hydrogen atom, D, F, Cl, Br, I, -N(R'')2, -CN, -NO2, -Si(R'')3, -B(OR'')2, -C(=O)R'', -P(=O)(R'')2, -S(=O)2R'', -OSO2R'', a linear or branched alkyl group having 1 to 30 carbon atoms, a cyclic alkyl group having 3 to 30 carbon atoms, a linear or branched alkoxy group having 1 to 30 carbon atoms, a cyclic alkoxy group having 2 to 30 carbon atoms, a linear or branched alkylthio group having 1 to 30 carbon atoms, a cyclic alkylthio group having 2 to 30 carbon atoms, a linear or branched alkenyl group having 2 to 30 carbon atoms, a cyclic alkenyl group having 3 to 30 carbon atoms, a linear or branched alkynyl group having 2 to 30 carbon atoms. [0046] The aryl group is selected from the group consisting of an aryl group having from 3 to 30 carbon atoms, a cyclic alkynyl group having from 3 to 30 carbon atoms, an aromatic group having from 5 to 60 carbon atoms, a heteroaromatic group having from 1 to 60 carbon atoms, an aryloxy group having from 5 to 40 carbon atoms, an arylthio group having from 5 to 40 carbon atoms, an aralkyl group having from 5 to 60 carbon atoms, a heteroaralkyl group having from 2 to 60 carbon atoms, a diarylamino group having from 10 to 40 carbon atoms, an arylheteroarylamino group having from 10 to 40 carbon atoms, and a diheteroarylamino group having from 10 to 40 carbon atoms. In the alkyl group, the alkoxy group, the alkylthio group, the alkenyl group and the alkynyl group, at least one or more hydrogen atoms may be further substituted by R'' (excluding a hydrogen atom), and one -CH 2 - group or two or more non-adjacent -CH 2 - groups in these groups may be substituted by -C(-R'')=C(-R'')-, -C≡C, -Si(-R'') 2 -, -C(=O)-, -NR''-, -O-, -S-, -CONR''- or a divalent aromatic group. In addition, one or more hydrogen atoms in these groups may be substituted by D, F, Cl, Br, I or -CN. The aromatic group, the heteroaromatic group, the aryloxy group, the arylthio group, the aralkyl group, the heteroaralkyl group, the diarylamino group, the arylheteroarylamino group and the diheteroarylamino group may each independently have at least one hydrogen atom further substituted with R″ (excluding hydrogen atoms). Two or more adjacent R″ may be bonded to each other to form an aliphatic, aromatic or heteroaromatic monocyclic or condensed ring. Each R'' is independently selected from a hydrogen atom, D, F, -CN, an aliphatic hydrocarbon group having from 1 to 20 carbon atoms, an aromatic group having from 5 to 20 carbon atoms, or a heteroaromatic group having from 1 to 20 carbon atoms. Two or more adjacent R″ may be joined together to form an aliphatic or aromatic or heteroaromatic monocyclic or fused ring, provided that R １２ and R １３ Any one of the above is a substituent represented by the following formula (2). 【Chemistry 2】 [In formula (2), the dashed line represents a bond to formula (1). ３１ represents an alkyl group, R ３２ represents an alkyl group or an aromatic group. ３１ and R ３２ may be further substituted.

2. R in the formula (1) ２１ and R ２２ 2. The iridium complex compound according to claim 1, wherein at least one of the above is a linear or branched alkyl group having 1 to 30 carbon atoms.

3. R in the formula (1) １３ The iridium complex compound according to claim 1 or 2, wherein: is a substituent represented by formula (2).

4. R in the formula (1) ６ ~R ９ The iridium complex compound according to any one of claims 1 to 3, wherein at least one of the following has as a substituent a linear or branched alkyl group having from 1 to 30 carbon atoms, a cyclic alkyl group having from 3 to 30 carbon atoms, an aromatic group having from 5 to 60 carbon atoms, or an aralkyl group having from 5 to 60 carbon atoms.

5. R in the formula (1) ６ ~R ９ The iridium complex compound according to any one of claims 1 to 3, wherein adjacent groups among

6. 6. An iridium complex compound-containing composition comprising the iridium complex compound according to claim 1 and an organic solvent.

7. The iridium complex compound-containing composition according to claim 6 , further comprising a compound represented by the following formula (3) having a maximum emission wavelength shorter than that of the iridium complex compound: 【Chemistry 3】 [In the above formula (3), R ３５ is an alkyl group having 1 to 20 carbon atoms, a (hetero)aralkyl group having 7 to 40 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a (hetero)aryloxy group having 3 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, an arylsilyl group having 6 to 20 carbon atoms, an alkylcarbonyl group having 2 to 20 carbon atoms, an arylcarbonyl group having 7 to 20 carbon atoms, an alkylamino group having 1 to 20 carbon atoms, an arylamino group having 6 to 20 carbon atoms, or a (hetero)aryl group having 3 to 30 carbon atoms. These groups may further have a substituent. R ３５ When multiple are present, they may be the same or different. c is an integer of 0 to 4. Ring A is any one of a pyridine ring, a pyrazine ring, a pyrimidine ring, an imidazole ring, an oxazole ring, a thiazole ring, a quinoline ring, an isoquinoline ring, a quinazoline ring, a quinoxaline ring, an azatriphenylene ring, a carboline ring, a benzothiazole ring, and a benzoxazole ring. Ring A may have a substituent, and the substituent is F, Cl, Br, an alkyl group having 1 to 20 carbon atoms, a (hetero)aralkyl group having 7 to 40 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a (hetero)aryloxy group having 3 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, an arylsilyl group having 6 to 20 carbon atoms, an alkylcarbonyl group having 2 to 20 carbon atoms, an arylcarbonyl group having 7 to 20 carbon atoms, an alkylamino group having 2 to 20 carbon atoms, an arylamino group having 6 to 20 carbon atoms, or a (hetero)aryl group having 3 to 20 carbon atoms. In addition, adjacent substituents bonded to ring A may be bonded to each other to form a further ring. When there are multiple rings A, they may be the same or different. L ２ represents an organic ligand, and n is an integer of 1 to 3.

8. The iridium complex compound-containing composition according to claim 6 or 7, further comprising a compound represented by the following formula (20): 【Chemistry 4】 [In the above formula (20), Each W independently represents CH or N, and at least one W is N; Xa １ , Ya １ , and Za １ each independently represents a divalent aromatic hydrocarbon group having from 6 to 30 carbon atoms which may have a substituent, or a divalent aromatic heterocyclic group having from 3 to 30 carbon atoms which may have a substituent, Xa ２ , Ya ２ and Za ２ each independently represents a hydrogen atom, an aromatic hydrocarbon group having from 6 to 30 carbon atoms which may have a substituent, or an aromatic heterocyclic group having from 3 to 30 carbon atoms which may have a substituent, g11, h11, and j11 each independently represent an integer of 0 to 6; At least one of g11, h11, and j11 is an integer of 1 or more; When g11 is 2 or more, a plurality of Xa １ may be the same or different, When h11 is 2 or more, multiple Ya １ may be the same or different, When j11 is 2 or more, multiple Za １ may be the same or different, R ２３ represents a hydrogen atom or a substituent, and four R ２３ may be the same or different, However, when g11, h11, or j11 is 0, the corresponding Xa ２ , Ya ２ , or Za ２ is not a hydrogen atom.)

9. A method for manufacturing an organic electroluminescent device having an anode, a cathode, and at least one organic layer located between the anode and the cathode on a substrate, comprising the steps of: A method for producing an organic electroluminescence device, wherein at least one of the organic layers is formed by a wet film-forming method using the iridium complex compound-containing composition according to any one of claims 6 to 8.

10. An organic electroluminescent device comprising an anode, a cathode, and at least one organic layer located between the anode and the cathode on a substrate, wherein at least one of the organic layers is a light-emitting layer comprising the iridium complex compound according to any one of claims 1 to 5.

11. The organic electroluminescent device according to claim 10 , further comprising a compound represented by the following formula (3) having a maximum emission wavelength shorter than that of the iridium complex compound: 【Chemistry 5】 [In the above formula (3), R ３５ is an alkyl group having 1 to 20 carbon atoms, a (hetero)aralkyl group having 7 to 40 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a (hetero)aryloxy group having 3 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, an arylsilyl group having 6 to 20 carbon atoms, an alkylcarbonyl group having 2 to 20 carbon atoms, an arylcarbonyl group having 7 to 20 carbon atoms, an alkylamino group having 1 to 20 carbon atoms, an arylamino group having 6 to 20 carbon atoms, or a (hetero)aryl group having 3 to 30 carbon atoms. These groups may further have a substituent. R ３５ When multiple are present, they may be the same or different. c is an integer of 0 to 4. Ring A is any one of a pyridine ring, a pyrazine ring, a pyrimidine ring, an imidazole ring, an oxazole ring, a thiazole ring, a quinoline ring, an isoquinoline ring, a quinazoline ring, a quinoxaline ring, an azatriphenylene ring, a carboline ring, a benzothiazole ring, and a benzoxazole ring. Ring A may have a substituent, and the substituent is F, Cl, Br, an alkyl group having 1 to 20 carbon atoms, a (hetero)aralkyl group having 7 to 40 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a (hetero)aryloxy group having 3 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, an arylsilyl group having 6 to 20 carbon atoms, an alkylcarbonyl group having 2 to 20 carbon atoms, an arylcarbonyl group having 7 to 20 carbon atoms, an alkylamino group having 2 to 20 carbon atoms, an arylamino group having 6 to 20 carbon atoms, or a (hetero)aryl group having 3 to 20 carbon atoms. In addition, adjacent substituents bonded to ring A may be bonded to each other to form a further ring. When there are multiple rings A, they may be the same or different. L ２ represents an organic ligand, and n is an integer of 1 to 3.

12. The organic electroluminescent device according to claim 10 or 11, wherein the light-emitting layer further comprises a compound represented by the following formula (20): 【Chemistry 6】 [In the above formula (20), Each W independently represents CH or N, and at least one W is N; Xa １ , Ya １ , and Za １ each independently represents a divalent aromatic hydrocarbon group having from 6 to 30 carbon atoms which may have a substituent, or a divalent aromatic heterocyclic group having from 3 to 30 carbon atoms which may have a substituent, Xa ２ , Ya ２ and Za ２ each independently represents a hydrogen atom, an aromatic hydrocarbon group having from 6 to 30 carbon atoms which may have a substituent, or an aromatic heterocyclic group having from 3 to 30 carbon atoms which may have a substituent, g11, h11, and j11 each independently represent an integer of 0 to 6; At least one of g11, h11, and j11 is an integer of 1 or more; When g11 is 2 or more, a plurality of Xa １ may be the same or different, When h11 is 2 or more, multiple Ya １ may be the same or different, When j11 is 2 or more, multiple Za １ may be the same or different, R ２３ represents a hydrogen atom or a substituent, and four R ２３ may be the same or different, However, when g11, h11, or j11 is 0, the corresponding Xa ２ , Ya ２ , or Za ２ is not a hydrogen atom.)

13. An organic EL display device comprising the organic electroluminescent device according to any one of claims 10 to 12.

14. An organic EL lighting device comprising the organic electroluminescent element according to any one of claims 10 to 12.

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