JPWO2019074093A1 - Polycyclic aromatic dimer compounds - Google Patents

Abstract

An excellent material that can be used as a material for an organic EL device, for example, by a dimer compound composed of two partial structures represented by the following general formula (1) and a linking group L1 that connects the two partial structures. Provided are polycyclic aromatic dimer compounds. [Chemical formula 224] The A ring, B ring and C ring are aryl rings or heteroaryl rings, Y1 is B and the like, X1 and X2 are> O and the like, and the linking group L1 is a single bond, carbon. Arylene with 6 to 30, heteroarylene with 2 to 30 carbon atoms, alkylene with 1 to 24 carbon atoms, alkenylene with 1 to 24 carbon atoms, alkynylene with 1 to 24 carbon atoms, -O-, -S-,> N -R, or a combination thereof, wherein R of> N-R is an aryl having 6 to 16 carbon atoms, a heteroaryl having 2 to 20 carbon atoms, an alkyl having 1 to 12 carbon atoms, or an alkyl having 3 to 16 carbon atoms. It is a cycloalkyl, and at least one hydrogen in the linking group L1 is substituted with an aryl having 6 to 16 carbon atoms, a heteroaryl having 2 to 20 carbon atoms, an alkyl having 1 to 12 carbon atoms or a cycloalkyl having 3 to 16 carbon atoms. At least one hydrogen in the dimer compound may be substituted with cyano, halogens or heavy hydrogens.

Description

The present invention relates to a polycyclic aromatic dimer compound, an organic electroluminescent device using the polycyclic aromatic dimer compound, an organic field effect transistor and an organic thin-film solar cell, and a display device and a lighting device.

Conventionally, display devices using electroluminescent elements have been studied in various ways because they can reduce power consumption and thinness. Furthermore, organic electroluminescent elements made of organic materials can be easily reduced in weight and size. Therefore, it has been actively examined. In particular, the development of organic materials having emission characteristics such as blue, which is one of the three primary colors of light, and the development of organic materials having charge transporting ability such as holes and electrons (which have the potential to become semiconductors and superconductors). Development has been actively studied for both high molecular weight compounds and low molecular weight compounds.

The organic EL element has a structure composed of a pair of electrodes composed of an anode and a cathode, and one layer or a plurality of layers containing an organic compound, which is arranged between the pair of electrodes. Layers containing organic compounds include light emitting layers and charge transport / injection layers that transport or inject charges such as holes and electrons, and various organic materials suitable for these layers have been developed.

As a material for a light emitting layer, for example, a benzofluorene compound or the like has been developed (International Publication No. 2004/061047). Further, as a hole transport material, for example, a triphenylamine-based compound has been developed (Japanese Patent Laid-Open No. 2001-172232). Further, as an electron transport material, for example, an anthracene compound and the like have been developed (Japanese Patent Laid-Open No. 2005-170911).

Further, in recent years, a material obtained by improving a triphenylamine derivative has been reported as a material used for an organic EL element or an organic thin-film solar cell (International Publication No. 2012/118164). This material was prepared with reference to N, N'-diphenyl-N, N'-bis (3-methylphenyl) -1,1'-biphenyl-4,4'-diamine (TPD), which had already been put into practical use. It is a material characterized in that its flatness is improved by connecting aromatic rings constituting triphenylamine. Other examples of such compounds can be found (International Publication No. 2011/107186, International Publication No. 2015/102118). For example, a compound having a conjugated structure having a large triplet exciton energy (T1) is useful as a material for a blue light emitting layer because it can emit phosphorescence having a shorter wavelength. Further, as an electron transport material or a hole transport material that sandwiches the light emitting layer, a compound having a novel conjugated structure having a large T1 is required.

The host material of the organic EL element is generally a molecule in which a plurality of existing aromatic rings such as benzene and carbazole are linked by a single bond or a phosphorus atom or a silicon atom. This is because the large HOMO-LUMO gap (bandgap Eg in the thin film) required for the host material is secured by connecting a large number of relatively small aromatic rings of the conjugated system. In addition, the host material of the organic EL element using a phosphorescent material or a heat activated delayed fluorescent material, high triplet excitation energy (E _T) is also required, the donor or acceptor properties of the aromatic ring and substituents in the molecule by connecting, to localize the SOMO1 and SOMO2 triplet excited state (T1), by reducing the exchange interaction between the two trajectories, it is possible to improve the triplet excitation energy (E _T) It becomes. However, the small aromatic ring of the conjugated system does not have sufficient redox stability, and the device using the molecule connecting the existing aromatic ring as the host material does not have a sufficient life. On the other hand, polycyclic aromatic compounds having an extended π conjugated system, generally, but the redox stability is excellent, because HOMO-LUMO gap and triplet excitation energy (band gap Eg of the thin film) (E _T) is low, It has been considered unsuitable for host materials.

International Publication No. 2004/061047 Japanese Unexamined Patent Publication No. 2001-172232 Japanese Patent Application Laid-Open No. 2005-170911 International Publication No. 2012/118164 International Publication No. 2011/107186 International Publication No. 2015/102118

As described above, various compounds have been developed as materials used for organic EL devices, but in order to increase the choices of materials for organic EL devices, it is desired to develop a material composed of a compound different from the conventional one. There is.

As a result of diligent studies to solve the above problems, the present inventors have made a polycyclic aromatic compound in which a plurality of aromatic rings are linked by a boron atom and an oxygen atom into a dimer to make it more excellent organic. We have found that it can be a material for devices and completed the present invention. That is, the present invention provides the following polycyclic aromatic dimer compounds, and further materials for organic EL devices containing the dimer compounds.

Item 1.
It is a dimer compound composed of two partial structures represented by the following general formula (1) and a linking group L1 that connects the two partial structures.
(In the above formula (1),
Rings A, B and C are independently aryl rings or heteroaryl rings, and at least one hydrogen in these rings may be substituted.
Y ¹ is B, P, P = O, P = S, Al, Ga, As, Si-R or Ge-R, and R of the Si-R and Ge-R is aryl, alkyl or cycloalkyl. Yes,
X ¹ and X ² are independently>O,>N-R,> S or> Se, and the R of> N-R may be substituted aryl, which may be substituted. Heteroaryl, optionally substituted alkyl or optionally substituted cycloalkyl, wherein the> N-R R is attached to the A, B and / or C rings by a linking group L2. May be good. )
The substructures represented by the formula (1) may be the same structure or different structures, but in the two substructures, Y ¹ is both B, X ¹ and X ² are both>. The case of O is excluded, and the case where Y ¹ is both P = O and X ¹ and X ² are both> O is excluded.
The linking group L1 is a single bond, an arylene having 6 to 30 carbon atoms, a hetero arylene having 2 to 30 carbon atoms, an alkylene having 1 to 24 carbon atoms, an alkenylene having 1 to 24 carbon atoms, and an alkynylene having 1 to 24 carbon atoms. -O-, -S-,> N-R, or a combination thereof, and the R of> N-R is an aryl having 6 to 16 carbon atoms, a heteroaryl having 2 to 20 carbon atoms, and 1 to 1 carbon atoms. It is an alkyl of 12 or a cycloalkyl of 3 to 16 carbon atoms, and at least one hydrogen in the linking group L1 is an aryl having 6 to 16 carbon atoms and a heteroaryl having 2 to 20 carbon atoms and having an alkyl or carbon number of 1 to 12 carbon atoms. It may be substituted with 3 to 16 cycloalkyls.
A dimer compound in which at least one hydrogen in the dimer compound may be substituted with cyano, halogen or deuterium.

Item 2.
In the above formula (1),
Rings A, B, and C are independently aryl and heteroaryl rings, and at least one hydrogen in these rings is a substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or Unsubstituted diarylamino, substituted or unsubstituted diheteroarylamino, substituted or unsubstituted aryl heteroarylamino, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted alkoxy or substituted or It may be substituted with an unsubstituted aryloxy, and these rings are 5- or 6-membered rings that share a bond with the fused bicyclic structure in the center of the above formula composed of Y ¹ , X ¹ and X ^2. Has a ring and
Y ¹ is B, P, P = O, P = S, Al, Ga, As, Si-R or Ge-R, and R of the Si-R and Ge-R is aryl, alkyl or cycloalkyl. Yes,
X ¹ and X ² are independently>O,>N-R,> S or> Se, and the R of> N-R may be substituted with alkyl or cycloalkyl, respectively. Alternatively, it may be heteroaryl, alkyl or cycloalkyl substituted with cycloalkyl, and the R of> N-R is selected from -O-, -S-, -C (-R) _2- and single bond. The linking group L2 may be bonded to the A ring, the B ring and / or the C ring, and the R of −C (−R) ₂₋ is hydrogen, alkyl or cycloalkyl, and
The substructures represented by the formula (1) may be the same structure or different structures, but in the two substructures, Y ¹ is both B, X ¹ and X ² are both>. The case of O is excluded, and the case where Y ¹ is both P = O and X ¹ and X ² are both> O is excluded.
The linking group L1 is a single bond, an arylene having 6 to 16 carbon atoms, a hetero arylene having 2 to 20 carbon atoms, an alkylene having 1 to 12 carbon atoms, an alkenylene having 1 to 12 carbon atoms, and an alkynylene having 1 to 12 carbon atoms. -O-, -S-,> N-R, or a combination thereof, and the R of> N-R is an aryl having 6 to 12 carbon atoms, a heteroaryl having 2 to 15 carbon atoms, and 1 to 1 carbon atoms. It is an alkyl of 6 or a cycloalkyl of 3 to 14 carbon atoms, and at least one hydrogen in the linking group L1 is an aryl having 6 to 12 carbon atoms, a heteroaryl having 2 to 15 carbon atoms, an alkyl or carbon having 1 to 6 carbon atoms. It may be substituted with the number 3-14 cycloalkyl.
At least one hydrogen in the dimer compound may be substituted with cyano, halogen or deuterium.
Item 2. The dimer compound according to Item 1.

Item 3.
Item 2. The dimer compound according to Item 1, wherein the partial structure is represented by the following general formula (2).
In the above formula (2),
R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ and R ¹¹ are independently hydrogen, aryl, heteroaryl, diarylamino, and di. Heteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkoxy or aryloxy, in which at least one hydrogen may be substituted with aryl, heteroaryl, alkyl or cycloalkyl, and R ¹ to Adjacent groups of R ¹¹ may be bonded to each other to form an aryl ring or a heteroaryl ring together with an a ring, a b ring or a c ring, and at least one hydrogen in the formed ring is an aryl or heteroaryl. , Diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkoxy or aryloxy, at least one of which is substituted with aryl, heteroaryl, alkyl or cycloalkyl. May be
Y ¹ is B, P, P = O, P = S, Al, Ga, As, Si-R or Ge-R, and R of the Si-R and Ge-R is an aryl having 6 to 12 carbon atoms. , Alkyl with 1 to 6 carbon atoms or cycloalkyl with 3 to 14 carbon atoms.
X ¹ and X ² are independently>O,>N-R,> S or> Se, and the R of> N-R is an aryl having 6 to 12 carbon atoms and 2 to 15 carbon atoms. Heteroaryl, alkyl with 1 to 6 carbons or cycloalkyl with 3 to 14 carbons, with> N-R R from -O-, -S-, -C (-R) _2- and single bond. The a ring, b ring and / or c ring may be bonded to the a ring, the b ring and / or the c ring by the connecting group L2 selected, and the R of −C (−R) ₂₋ is an alkyl having 1 to 6 carbon atoms or 3 to 3 carbon atoms. 14 cycloalkyl, and
The substructures represented by the formula (2) may be the same structure or different structures, but in the two substructures, Y ¹ is both B, X ¹ and X ² are both>. The case of O is excluded, and the case where Y ¹ is both P = O and X ¹ and X ² are both> O is excluded.
The linking group L1 includes a single bond, an arylene having 6 to 12 carbon atoms, a heteroarylene having 2 to 15 carbon atoms, an alkylene having 1 to 6 carbon atoms, an alkenylene having 1 to 6 carbon atoms, and an alkynylene having 1 to 6 carbon atoms. -O-, -S-,> N-R, or a combination thereof, and the R of> N-R is an aryl having 6 to 12 carbon atoms, a heteroaryl having 2 to 15 carbon atoms, and 1 to 1 carbon atoms. It is an alkyl of 6 or a cycloalkyl of 3 to 14 carbon atoms.
At least one hydrogen in the dimer compound may be substituted with cyano, halogen or deuterium.

Item 4.
In the above formula (2),
R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ and R ¹¹ are independently hydrogen, aryl and carbon with 6 to 30 carbon atoms, respectively. number 2-30 heteroaryl, diarylamino (where aryl is aryl of 6 to 12 carbon atoms), cycloalkyl alkyl or 3-20 carbon atoms having 1 to 20 carbon atoms, ^also, of R 1 ^{to R 11} Adjacent groups thereof may be bonded to each other to form an aryl ring having 9 to 16 carbon atoms or a heteroaryl ring having 6 to 15 carbon atoms together with the a ring, b ring or c ring, and in the formed ring. At least one hydrogen may be substituted with an aryl having 6 to 10 carbon atoms, an alkyl having 1 to 6 carbon atoms, or a cycloalkyl having 3 to 14 carbon atoms.
Y ¹ is B, P, P = O, P = S or Si-R, and R of the Si-R is an aryl having 6 to 10 carbon atoms, an alkyl having 1 to 4 carbon atoms, or 5 to 10 carbon atoms. Cycloalkyl,
X ¹ and X ² are independently>O,> N-R or> S, and the R of> N-R is an aryl having 6 to 10 carbon atoms and an alkyl or carbon having 1 to 4 carbon atoms. It is a cycloalkyl of number 5-10, and
Two of the substructures represented by the formula (2) are the same structure, except when Y ¹ is both B and X ¹ and X ² are both> O in the ^two substructures, and Y Excludes cases where ¹ is both P = O and X ¹ and X ² are both> O.
The linking group L1 is a single bond, an arylene having 6 to 12 carbon atoms, an alkylene having 1 to 6 carbon atoms, an alkenylene having 1 to 6 carbon atoms, -O-, -S-,> N-R, or any of these. It is a combination, and R of> N-R is an aryl having 6 to 10 carbon atoms.
At least one hydrogen in the dimer compound may be substituted with cyano, halogen or deuterium.
Item 2. The dimer compound according to Item 3.

Item 5.
Item 2. The dimer compound according to Item 1, which is represented by any of the following chemical structural formulas.

Item 6.
A material for an organic device containing the dimer compound according to any one of Items 1 to 5.

Item 7.
Item 6. The material for an organic device according to Item 6, wherein the material for an organic device is a material for an organic electroluminescent device, a material for an organic field effect transistor, or a material for an organic thin film solar cell.

Item 8.
Item 6. The material for an organic electroluminescent device, which is a material for a light emitting layer.

Item 9.
An organic electroluminescent device having a pair of electrodes composed of an anode and a cathode, and a light emitting layer arranged between the pair of electrodes and containing the light emitting layer material according to Item 8.

Item 10.
It has an electron transport layer and / or an electron injection layer arranged between the cathode and the light emitting layer, and at least one of the electron transport layer and the electron injection layer is a quinolinol-based metal complex, a pyridine derivative, or a phenanthroline derivative. Item 9. The organic electroluminescent element according to Item 9, which contains at least one selected from the group consisting of a borane derivative and a benzimidazole derivative.

Item 11.
The electron transporting layer and / or electron injecting layer further comprises an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal oxide, an alkali metal halide, an alkaline earth metal oxide, and an alkaline earth metal. Item 10. Contains at least one selected from the group consisting of halides, oxides of rare earth metals, halides of rare earth metals, organic complexes of alkali metals, organic complexes of alkaline earth metals and organic complexes of rare earth metals. The organic electric field light emitting element according to.

Item 12.
A display device or a lighting device including the organic electroluminescent element according to any one of Items 9 to 11.

According to a preferred embodiment of the present invention, it is possible to provide an excellent polycyclic aromatic dimer compound that can be used as a material for an organic EL device, for example, and it is excellent to use this dimer compound. An organic device such as an organic EL element can be provided.

Specifically, the present inventors have found that a dimer of a polycyclic aromatic compound in which aromatic rings are linked by hetero elements such as boron, phosphorus, oxygen, nitrogen, and sulfur has a large HOMO-LUMO gap (band in a thin film). It was found to have a gap Eg) and high triplet excitation energy (E _T). This is because the 6-membered ring containing the hetero element has low aromaticity, so that the decrease in the HOMO-LUMO gap due to the expansion of the conjugated system is suppressed, and the triplet excited state (T1) is due to the electronic perturbation of the hetero element. It is considered that the cause is the localization of SOMO1 and SOMO2 in). Further, in the polycyclic aromatic dimer compound containing a hetero element according to the present invention, the exchange interaction between the two orbitals becomes small due to the localization of SOMO1 and SOMO2 in the triplet excited state (T1). Since the energy difference between the triplet excited state (T1) and the singlet excited state (S1) is small and exhibits thermally active delayed fluorescence, it is also useful as a fluorescent material for organic EL elements. Further, the material having high triplet excitation energy (E _T), is also useful as an electron transport layer and a hole transport layer of an organic EL element utilizing a phosphorescent organic EL device and heat activated delayed fluorescence. Furthermore, since these polycyclic aromatic dimer compounds can arbitrarily move the energies of HOMO and LUMO by introducing substituents, the ionization potential and electron affinity should be optimized according to the peripheral materials. Is possible.

Further, the dimer compound of the present invention can be expected to lower the melting point and sublimation temperature by introducing a cycloalkyl group. This means that in sublimation purification, which is almost indispensable as a method for purifying materials for organic devices such as organic EL devices that require high purity, it can be purified at a relatively low temperature, so that thermal decomposition of the material can be avoided. Means. This also applies to the vacuum vapor deposition process, which is a powerful means for manufacturing organic devices such as organic EL devices, and since the process can be carried out at a relatively low temperature, thermal decomposition of the material can be avoided. As a result, a high-performance organic device can be obtained. In addition, since the introduction of the cycloalkyl group improves the solubility in an organic solvent, it can be applied to device fabrication using a coating process. However, the present invention is not particularly limited to these principles.

It is a schematic sectional drawing which shows the organic EL element which concerns on this embodiment. Absorption, fluorescence and phosphorescence spectra of compound (1-201).

1. 1. Polycyclic Aromatic Dimer Compound The present invention is a dimer compound composed of two partial structures represented by the following general formula (1) and a linking group L1 that connects the two partial structures. The present invention is preferably a dimer compound composed of two partial structures represented by the following general formula (2) and a linking group L1 that connects the two partial structures. The definition of each code in all the structural formulas used in the following description is the same as the above-mentioned definition.

The A ring, B ring, and C ring in the general formula (1) are independently aryl rings or heteroaryl rings, and at least one hydrogen in these rings may be substituted with a substituent. This substituent is a substituted or unsubstituted aryl, a substituted or unsubstituted heteroaryl, a substituted or unsubstituted diarylamino, a substituted or unsubstituted diheteroarylamino, a substituted or unsubstituted aryl heteroarylamino (with aryl). Amino groups with heteroaryl), substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted alkoxy or substituted or unsubstituted aryloxy are preferred. Examples of the substituent when these groups have a substituent include aryl, heteroaryl, alkyl and cycloalkyl. Further, the above aryl ring or heteroaryl ring is bonded to a condensed bicyclic structure (hereinafter, this structure is also referred to as "D structure") in the center of the general formula (1) composed of Y ¹ , X ¹ and X ^2. It is preferred to have a shared 5- or 6-membered ring.

Here, the "condensed bicyclic structure (D structure)" means that two saturated hydrocarbon rings including Y ¹ , X ¹ and X ² shown in the center of the general formula (1) are condensed. Means structure. Further, the "6-membered ring sharing a bond with the condensed bicyclic structure" means, for example, an a ring (benzene ring (6-membered ring)) condensed with the D structure as shown by the general formula (2). .. Further, "the aryl ring (which is the A ring) or the heteroaryl ring has the 6-membered ring" means that the A-ring is formed only by the 6-membered ring or includes the 6-membered ring. This means that another ring or the like is condensed with this 6-membered ring to form an A ring. In other words, the "aryl ring having a 6-membered ring (which is an A ring) or a heteroaryl ring" as used herein means that a 6-membered ring constituting all or a part of the A ring is condensed with the D structure. Means to be. The same description applies to "B ring (b ring)", "C ring (c ring)", and "5-membered ring".

Ring A (or B ring, C ring) in Formula (1) has the general formula (2) a ring in its substituents ^R 1 to R ³ (or b ring and substituents thereof ^R 8 ^{to R} 11, c ring and corresponding to the substituent ^R 4 ^{~R 7).} That is, the general formula (2) corresponds to a structural formula in which "A to C rings having a 6-membered ring" is selected as the A to C rings of the general formula (1). In that sense, each ring of the general formula (2) is represented by lowercase letters a to c.

In general formula (2), a ring, a ring adjacent groups are bonded to one of the substituents R ¹ to R ¹¹ of b ring and c rings, with b ring or c ring aryl or heteroaryl ring It may be formed, and at least one hydrogen in the formed ring may be substituted with aryl, heteroaryl, diarylamino, diheteroarylamino, aryl heteroarylamino, alkyl, cycloalkyl, alkoxy or aryloxy. Often, at least one hydrogen in these may be substituted with aryl, heteroaryl, alkyl or cycloalkyl. Therefore, the partial structure represented by the general formula (2) is shown in the following formulas (2-1) and (2-2) depending on the mutual bonding form of the substituents in the a ring, b ring and c ring. In addition, the ring structure that constitutes the partial structure changes. The A'ring, B'ring and C'ring in each formula correspond to the A ring, B ring and C ring in the general formula (1), respectively.

The formula (2-1) and ring A ', B' in the formula (2-2) ring and C 'ring, will be described in the general formula (2), adjoining of the substituents ^R 1 ^{to R 11} It represents an aryl ring or a heteroaryl ring formed by bonding a ring, a b ring, and a c ring, respectively (a fused ring formed by condensing another ring structure on the a ring, b ring, or c ring). It can be said that). Although not shown in the formula, there is also a partial structure in which all of the a ring, b ring and c ring are changed to A'ring, B'ring and C'ring. Further, as can be seen from the above equations (2-1) and (2-2), for example, R ⁸ of b ring and R ⁷ of c ring, R ¹¹ of b ring and R ^{1 of} a ring, and c ring. R ⁴ and R ^{3 of the} a ring do not correspond to "adjacent groups", and they do not bond with each other. That is, the "adjacent group" means an adjacent group on the same ring.

The partial structures represented by the above formulas (2-1) and (2-2) are represented by, for example, formulas (1-9) and formulas (1-99) listed as specific compounds described later. Corresponds to the partial structure of various compounds. That is, the A'ring (or B') formed by condensing a benzene ring, an indol ring, a pyrrole ring, a benzofuran ring, a benzothiophene ring, or the like with a benzene ring which is, for example, a ring (or b ring or c ring). It is a partial structure having a ring or C'ring), and the formed fused ring A'(or fused ring B'or fused ring C') is a naphthalene ring, a carbazole ring, an indol ring, a dibenzofuran ring or a dibenzothiophene, respectively. Such as a ring.

Y ¹ in the general formula (1) is B, P, P = O, P = S, Al, Ga, As, Si-R or Ge-R, and R of the Si-R and Ge-R is aryl. , Alkyl or cycloalkyl. In the case of P = O, P = S, Si-R or Ge-R, the atom bonded to the A ring, B ring or C ring is P, Si or Ge. As Y ¹ , B, P, P = O, P = S or Si—R is preferable, and B is particularly preferable. This explanation is the same for Y ¹ in the general formula (2).

X ¹ and X ² in the general formula (1) are independently>O,>N-R,> S or> Se, and the R in> N-R may be substituted aryl. Heteroaryl which may be substituted, alkyl which may be substituted or cycloalkyl which may be substituted, and R of> N-R is the A ring, B ring and / or C of the linking group L2. It may be bonded to the ring, and the linking group L2 is preferably a single bond, −O−, −S− or −C (−R) _2- . In addition, R of the said "−C (−R) ₂₋ ” is hydrogen, alkyl or cycloalkyl. This explanation is the same for X ¹ and X ² in the general formula (2).

Here, the provision that "R of> N-R is bonded to the A ring, the B ring and / or the C ring by the connecting group L2" in the general formula (1) is described in the general formula (2) as "> N-R R is attached to the a, b and / or c rings by a linking group L2 selected from -O-, -S-, -C (-R) _2- and a single bond. Corresponds to the provision of.
This specification can be expressed by a partial structure represented by the following formula (2-3-1), in which X ¹ and X ² have a ring structure incorporated into the condensed ring B'and the condensed ring C'. That is, for example, the B'ring (or ring) formed by condensing other rings so as to incorporate X ¹ (or X ² ) into the benzene ring which is the b ring (or c ring) in the general formula (2). It is a compound having a C'ring). The formed fused ring B'(or fused ring C') is, for example, a phenoxazine ring, a phenothiazine ring, or an acridine ring.
Further, the above specification is a portion having a ring structure in which X ¹ and / or X ² is incorporated into the condensed ring A', which is represented by the following formula (2-3-2) or formula (2-3-3). It can also be expressed in structure. That is, for example, in a partial structure having an A'ring formed by condensing other rings so as to incorporate X ¹ (and / or X ² ) into the benzene ring which is the a ring in the general formula (2). is there. The formed fused ring A'is, for example, a phenoxazine ring, a phenothiazine ring, or an acridine ring.

Examples of the "aryl ring" which is the A ring, B ring, and C ring of the general formula (1) include an aryl ring having 6 to 30 carbon atoms, and an aryl ring having 6 to 16 carbon atoms is preferable. Aryl rings of 6 to 12 are more preferable, and aryl rings having 6 to 10 carbon atoms are particularly preferable. This "aryl ring" is defined by the general formula (2) as "an aryl ring formed by bonding adjacent groups among R ^{1 to} R ¹¹ together with an a ring, a b ring, or a c ring". In addition, since the a ring (or b ring, c ring) is already composed of a benzene ring having 6 carbon atoms, the carbon having a total carbon number of 9 is the lower limit of the fused ring in which a 5-membered ring is condensed. It becomes a number.

Specific examples of the "aryl ring" include a benzene ring which is a monocyclic system, a biphenyl ring which is a bicyclic system, a naphthalene ring which is a fused bicyclic system, and a terphenyl ring (m-terphenyl, o) which is a tricyclic system. -Terphenyl, p-terphenyl), fused tricyclics, acenaphthylene ring, fluorene ring, phenalene ring, phenanthrene ring, condensed tetracyclic triphenylene ring, pyrene ring, naphthalene ring, fused pentacyclic system. Examples include a perylene ring and a pentacene ring.

Examples of the "heteroaryl ring" which is the A ring, B ring, and C ring of the general formula (1) include a heteroaryl ring having 2 to 30 carbon atoms, and a heteroaryl ring having 2 to 25 carbon atoms is preferable. , A heteroaryl ring having 2 to 20 carbon atoms is more preferable, a heteroaryl ring having 2 to 15 carbon atoms is further preferable, and a heteroaryl ring having 2 to 10 carbon atoms is particularly preferable. Further, examples of the "heteroaryl ring" include a heterocycle containing 1 to 5 heteroatoms selected from oxygen, sulfur and nitrogen in addition to carbon as ring-constituting atoms. In addition, this "heteroaryl ring" is a heteroaryl formed by bonding adjacent groups among "R ^{1 to} R ¹¹ " defined by the general formula (2) together with an a ring, a b ring or a c ring. Since the a ring (or b ring, c ring) is already composed of a benzene ring having 6 carbon atoms, the total carbon number 6 of the fused ring in which a 5-membered ring is condensed is the lower limit. It becomes the carbon number of.

Specific "heteroaryl rings" include, for example, a pyrrole ring, an oxazole ring, an isooxazole ring, a thiazole ring, an isothiazole ring, an imidazole ring, an oxazole ring, a thiazazole ring, a triazole ring, a tetrazole ring, a pyrazole ring, and the like. Pyridin ring, pyrimidine ring, pyridazine ring, pyrazine ring, triazine ring, indole ring, isoindole ring, 1H-indazole ring, benzimidazole ring, benzoxazole ring, benzothiazole ring, 1H-benzotriazole ring, quinoline ring, isoquinoline ring , Synnoline ring, quinazoline ring, quinoxalin ring, phthalazine ring, naphthylidine ring, purine ring, pteridine ring, carbazole ring, aclysine ring, phenoxatiein ring, phenoxazine ring, phenothiazine ring, phenazine ring, indridin ring, furan ring, Examples thereof include a benzofuran ring, an isobenzofuran ring, a dibenzofuran ring, a thiophene ring, a benzothiophene ring, a dibenzothiophene ring, a flazan ring, and a thiantolen ring.

At least one hydrogen in the "aryl ring" or "heteroaryl ring" is the first substituent, a substituted or unsubstituted "aryl", a substituted or unsubstituted "heteroaryl", a substituted or unsubstituted. "Diarylamino", substituted or unsubstituted "diheteroarylamino", substituted or unsubstituted "arylheteroarylamino", substituted or unsubstituted "alkyl", substituted or unsubstituted "cycloalkyl", substituted or It may be substituted with an unsubstituted "alkoxy" or a substituted or unsubstituted "aryloxy", and the aryl of "aryl", "heteroaryl", or "diarylamino" as the first substituent is , "Diheteroarylamino" heteroaryl, "arylheteroarylamino" aryl and heteroaryl, and "aryloxy" aryl as the above-mentioned "aryl ring" or "heteroaryl ring" monovalent group. can give.

The "alkyl" as the first substituent may be either a straight chain or a branched chain, and examples thereof include a linear alkyl having 1 to 24 carbon atoms and a branched chain alkyl having 3 to 24 carbon atoms. An alkyl having 1 to 18 carbon atoms (branched chain alkyl having 3 to 18 carbon atoms) is preferable, an alkyl having 1 to 12 carbon atoms (branched chain alkyl having 3 to 12 carbon atoms) is more preferable, and an alkyl having 1 to 6 carbon atoms is more preferable. (Branched chain alkyl having 3 to 6 carbon atoms) is more preferable, and alkyl having 1 to 4 carbon atoms (branched chain alkyl having 3 to 4 carbon atoms) is particularly preferable.

Specific alkyls include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, isopentyl, neopentyl, t-pentyl, n-hexyl, 1-methyl. Pentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 1-methylhexyl, n-octyl, t-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propyl Pentyl, n-nonyl, 2,2-dimethylheptyl, 2,6-dimethyl-4-heptyl, 3,5,5-trimethylhexyl, n-decyl, n-undecyl, 1-methyldecyl, n-dodecyl, n- Examples thereof include tridecyl, 1-hexylheptyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl and n-eicosyl.

The "cycloalkyl" as the first substituent includes cycloalkyl having 3 to 24 carbon atoms, cycloalkyl having 3 to 20 carbon atoms, cycloalkyl having 3 to 16 carbon atoms, and cycloalkyl having 3 to 14 carbon atoms. , Cycloalkyl having 5 to 10 carbon atoms, cycloalkyl having 5 to 8 carbon atoms, cycloalkyl having 5 to 6 carbon atoms, cycloalkyl having 5 carbon atoms, and the like.

Specific cycloalkyls include cyclopropyl, methylcyclopropyl, cyclobutyl, methylcyclobutyl, cyclopentyl, methylcyclopentyl, cyclohexyl, methylcyclohexyl, cycloheptyl, methylcycloheptyl, cyclooctyl, methylcyclooctyl, cyclononyl, and methylcyclononyl. , Cyclodecyl, methylcyclodecyl, bicyclo [1.0.1] butyl, bicyclo [1.1.1] pentyl, bicyclo [2.0.1] pentyl, bicyclo [1.2.1] hexyl, bicyclo [3] .0.1] Hexyl, bicyclo [2.1.2] heptyl, bicyclo [2.2.2] octyl, adamantyl, diamantyl, decahydronaphthalenyl, decahydroazulenyl and the like.

Examples of the "alkoxy" as the first substituent include alkoxy having a linear chain having 1 to 24 carbon atoms or a branched chain having 3 to 24 carbon atoms. Alkoxy having 1 to 18 carbon atoms (alkoxy of branched chains having 3 to 18 carbon atoms) is preferable, and alkoxy having 1 to 12 carbon atoms (alkoxy of branched chains having 3 to 12 carbon atoms) is more preferable, and alkoxy having 1 to 6 carbon atoms is more preferable. Alkoxy (alkoxy of branched chains having 3 to 6 carbon atoms) is more preferable, and alkoxy having 1 to 4 carbon atoms (alkoxy of branched chains having 3 to 4 carbon atoms) is particularly preferable.

Specific examples of alkoxy include methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, s-butoxy, t-butoxy, pentyloxy, hexyloxy, heptyloxy, and octyloxy.

The first substituent, substituted or unsubstituted "aryl", substituted or unsubstituted "heteroaryl", substituted or unsubstituted "diarylamino", substituted or unsubstituted "diheteroarylamino", substituted Or unsubstituted "aryl heteroarylamino", substituted or unsubstituted "alkyl", substituted or unsubstituted "cycloalkyl", substituted or unsubstituted "alkoxy", or substituted or unsubstituted "aryloxy" May have at least one hydrogen in them substituted with a second substituent, as described as substituted or unsubstituted. Examples of the second substituent include aryl, heteroaryl, alkyl and cycloalkyl, and specific groups thereof are monovalent groups of the above-mentioned "aryl ring" or "heteroaryl ring". You can also refer to the description of "alkyl" or "cycloalkyl" as the first substituent. Further, in aryl and heteroaryl as the second substituent, at least one hydrogen in them is aryl such as phenyl (specific example is the group described above), alkyl such as methyl (specific example is the group described above), and cyclohexyl. A group substituted with a cycloalkyl (specific example is the group described above) such as, is also included in aryl or heteroaryl as the second substituent. As an example, when the second substituent is a carbazolyl group, the carbazolyl group in which at least one hydrogen at the 9-position is substituted with an aryl such as phenyl, an alkyl such as methyl, or a cycloalkyl group such as cyclohexyl is also the second. It is contained in heteroaryl as a substituent of.

Aryl, heteroaryl, dialylamino aryl, diheteroarylamino heteroaryl, aryl heteroarylamino aryl and heteroaryl, or aryloxy aryl in the general formula (2) R ^{1 to} R ¹¹ are general formulas. Examples thereof include monovalent groups of the "aryl ring" or "heteroaryl ring" described in (1). Further, as the alkyl, cycloalkyl or alkoxy in R ^{1 to} R ¹¹ , refer to the description of “alkyl”, “cycloalkyl” and “alkoxy” as the first substituent in the above-mentioned explanation of the general formula (1). can do. The same applies to aryl, heteroaryl, alkyl or cycloalkyl as substituents to these groups. Further, when adjacent groups of R ^{1 to} R ¹¹ are bonded to each other to form an aryl ring or a heteroaryl ring together with an a ring, a b ring or a c ring, a heteroaryl which is a substituent to these rings is obtained. , Diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkoxy or aryloxy, and the additional substituents aryl, heteroaryl, alkyl or cycloalkyl.

The R of Si-R and Ge-R in Y ¹ of the general formula (1) is aryl, alkyl or cycloalkyl, and examples of the aryl, alkyl or cycloalkyl include the above-mentioned groups. In particular, aryls having 6 to 10 carbon atoms (for example, phenyl, naphthyl, etc.) and alkyls having 1 to 4 carbon atoms (for example, methyl, ethyl, etc.) are preferable. This explanation is the same for Y ¹ in the general formula (2).

The R of> N-R in X ¹ and X ² of the general formula (1) is an aryl, heteroaryl, alkyl or cycloalkyl optionally substituted with the second substituent described above, and the aryl, heteroaryl, At least one hydrogen in alkyl or cycloalkyl may be substituted with, for example, alkyl or cycloalkyl. Examples of the aryl, heteroaryl, alkyl or cycloalkyl include the groups described above. In particular, aryls having 6 to 10 carbon atoms (for example, phenyl, naphthyl, etc.), heteroaryls having 2 to 15 carbon atoms (for example, carbazolyl), alkyls having 1 to 4 carbon atoms (for example, methyl, ethyl, etc.), carbon atoms 3 to 16 Cycloalkyl (eg, bicyclooctyl, adamantyl, etc.) is preferred. This explanation is the same for X ¹ and X ² in the general formula (2).

The R of the linking group L2 in the general formula (1) "-C (-R) _2- " is hydrogen, alkyl or cycloalkyl, and examples of the alkyl or cycloalkyl include the above-mentioned groups. In particular, alkyls having 1 to 4 carbon atoms (for example, methyl, ethyl, etc.) are preferable. This explanation is the same for "-C (-R) _2- " which is the connecting group L2 in the general formula (2).

The compound of the present invention is a compound in which the partial structures represented by the two formulas (1) are bonded by the linking group L1, and the two partial structures may have the same structure or different structures. , Preferably the same structure. However, in the two substructures, when Y ¹ is both B, X ¹ and X ² are both> O, it is excluded from the present invention, and Y ¹ is both P = O, X ¹ and X ² are both>. The case of O is also excluded from the present invention.

The linking group L1 is a single bond, an arylene having 6 to 30 carbon atoms, a heteroarylene having 2 to 30 carbon atoms, an alkylene having 1 to 24 carbon atoms, an alkenylene having 1 to 24 carbon atoms, an alkynylene having 1 to 24 carbon atoms, and − O-, -S-,> N-R, or a combination thereof. The R of> N-R is an aryl having 6 to 16 carbon atoms, a heteroaryl having 2 to 20 carbon atoms, an alkyl having 1 to 12 carbon atoms, or a cycloalkyl having 3 to 16 carbon atoms. At least one hydrogen in the linking group L1 may be substituted with an aryl having 6 to 16 carbon atoms, a heteroaryl having 2 to 20 carbon atoms, an alkyl having 1 to 12 carbon atoms or a cycloalkyl having 3 to 16 carbon atoms.

Regarding "arylene", "heteroarylene" and "alkylene" in the linking group L1, the description of "aryl", "heteroaryl" and "alkyl" in the partial structure of the formula (1) is used as a divalent group. It can be quoted instead of the explanation. Further, "alkenylene" is a group having one or more -C = C- groups in alkylene, and "alkynylene" has one or two or more -C≡C- groups in alkylene. As a group, one or two or more -CH ₂ -groups can be replaced with -C = C- group or -C≡C- group, respectively, in the above description of "alkylene".

"Aryl", "heteroaryl" and "alkyl", "cycloalkyl" as R> N-R in linking group L1, and "aryl", "heteroaryl" substituted with at least one hydrogen in linking group L1 , "Alkyl" and "Cycloalkyl", the description of "aryl", "heteroaryl", "alkyl" and "cycloalkyl" in the partial structure of formula (1) can be cited.

The linking group L1 is an arylene having 6 to 30 carbon atoms, a heteroarylene having 2 to 30 carbon atoms, an alkylene having 1 to 24 carbon atoms, an alkenylene having 1 to 24 carbon atoms, an alkynylene having 1 to 24 carbon atoms, −O−,. It may be a group formed by combining at least one group selected from the group consisting of —S— and> N—R. This specific example will be illustrated in the specific compound described later.

The bonding location between the connecting group L1 and the partial structure of the formula (1) or the formula (2) is arbitrary. Specific binding sites will be exemplified in specific compounds described later.

Further, at least one hydrogen in the dimer compound of the present invention may be substituted with cyano, halogen or deuterium. For example, in the formula (1), A ring, B ring, C ring (A to C rings are aryl rings or heteroaryl rings), substituents to A to C rings, Y ¹ is Si-R or Ge-R. Hydrogen in R (= alkyl, aryl, cycloalkyl) when is and R (= aryl, heteroaryl, alkyl, cycloalkyl) when X ¹ and X ² are> N-R can be substituted. However, among these, an embodiment in which all or a part of hydrogen in aryl or heteroaryl is substituted can be mentioned. Halogen is fluorine, chlorine, bromine or iodine.

In addition, the dimer compound according to the present invention can be used as a material for organic devices. Examples of the organic device include an organic electroluminescent device, an organic field effect transistor, and an organic thin film solar cell. In particular, in an organic electroluminescent device, as the dopant material of the light emitting layer, Y ¹ is B, X ¹ and X ² are partial structures of> N-R, Y ¹ is B, X ¹ is> O, and X ² are. A dimer compound having a partial structure of> N-R is preferable, and as a host material of the light emitting layer, a dimer having a partial structure of Y ¹ is B, X ¹ is> O, and X ² is> N-R. Body compounds are preferably used.

As a more specific example of the dimer compound of the present invention, for example, a compound represented by the following chemical structural formula can be mentioned. In the chemical structural formula, Me is a methyl group, tBu is a tert-butyl group, and Ph is a phenyl group.

2. 2. Method for Producing Polycyclic Aromatic Dimeric Compound The dimer compound of the present invention has two polycyclic aromatic compounds after producing a polycyclic aromatic compound corresponding to a partial structure represented by the general formulas (1) and (2). The polycyclic aromatic compound was bonded at the linking group L1 by a known method, or two intermediates for forming the polycyclic aromatic compound were bonded at the linking group L1 and bonded at the linking group L1. It can be produced by polycyclic aromaticizing the two intermediate portions.

A method for producing a polycyclic aromatic compound corresponding to a partial structure represented by the general formulas (1) and (2) is already known, and the method described in International Publication No. 2015/102118 (Patent Document 6) is used. It can be used as a reference. The basic manufacturing method will be described below. Basically, in a polycyclic aromatic compound, first, the A ring (a ring), the B ring (b ring), and the C ring (c ring) are bonded by a bonding group (a group containing X ¹ and X ² ). to produce intermediate by (first reaction), subsequently, a ring (a ring), B ring (b ring) and be coupled with C ring (c ring) a linking group (group including Y ¹⁾ The final product can be produced in (second reaction). In the first reaction, for example, in the case of an etherification reaction, a general reaction such as a nucleophilic substitution reaction or an Ullmann reaction can be used, and in the case of an amination reaction, a general reaction such as a Buchwald-Hartwig reaction can be used. Further, in the second reaction, a tandem hetero-Friedel-Crafts reaction (continuous aromatic electrophilic substitution reaction, the same applies hereinafter) can be used.

The second reaction, as shown in the following scheme (1) or (2), A ring (a ring), B ring (b ring) and C rings (c ring) be the reaction of introducing a ^{Y 1} to bind As an example, the case where Y ¹ is a boron atom and X ¹ and X ² are> N-R is shown below. First, the hydrogen atom between X ¹ and X ² is orthometalated with n-butyllithium, sec-butyllithium, t-butyllithium or the like. Next, boron trichloride, boron tribromide, etc. are added, the metal of lithium-boron is exchanged, and then Bronsted bases such as N, N-diisopropylethylamine are added to cause a tandem Bora Friedel-Crafts reaction. You can get things. In the second reaction, a Lewis acid such as aluminum trichloride may be added to accelerate the reaction.

By appropriately selecting the above-mentioned production method and appropriately selecting the raw material to be used, a polycyclic aromatic having a substituent at a desired position, Y ¹ being a boron atom, and X ¹ and X ² being> N-R. Group compounds can be produced. Further, the compound in which X ¹ and X ² are>O,> S or> Se can be similarly produced by appropriately changing the raw materials.

For compounds in which Y ¹ is phosphorus sulfide (P = S), phosphorus oxide (P = O) or phosphorus atom (P), in schemes (1) and (2), boron trichloride, boron tribromide, etc. Alternatively, by reacting phosphorus trichloride (PCl ₃ ) with sulfur (S ₈ ), a compound in which Y ¹ is phosphor sulfide can be obtained. The obtained Rinsurufido compound Y ¹ is able to obtain the compound is a phosphorus oxide by treatment with at m- chloroperbenzoic acid (m-CPBA), Y ¹ by treatment with triethyl phosphine phosphorus A compound that is an atom can be obtained.

Further, a compound in which Y ¹ is Al, Ga, As, Si-R or Ge-R can also be similarly produced by appropriately changing the raw materials.

As a method for binding the polycyclic aromatic compound corresponding to the partial structure represented by the general formulas (1) and (2) produced as described above with the linking group L1, a known method can be used. .. Further, a known method can also be used as a method of binding at the linking group L1 at the stage of the intermediate for forming a polycyclic aromatic compound.

The dimer compound of the present invention also includes a compound in which at least a part of hydrogen atoms is substituted with cyano, halogen or deuterium, but such a compound is cyanated or halogenated at a desired location. , Or by using a deuterated raw material, it can be produced in the same manner as described above.

3. 3. Organic device The dimer compound according to the present invention can be used as a material for an organic device. Examples of the organic device include an organic electroluminescent device, an organic field effect transistor, an organic thin film solar cell, and the like.

3-1. Organic electroluminescent device The dimer compound according to the present invention can be used, for example, as a material for an organic electroluminescent device. Hereinafter, the organic EL element according to the present embodiment will be described in detail with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an organic EL device according to the present embodiment.

<Structure of organic electroluminescent device>
The organic electroluminescent element 100 shown in FIG. 1 is above the substrate 101, the anode 102 provided on the substrate 101, the hole injection layer 103 provided on the anode 102, and the hole injection layer 103. The hole transport layer 104 provided in the hole transport layer 104, the light emitting layer 105 provided on the hole transport layer 104, the electron transport layer 106 provided on the light emitting layer 105, and the electron transport layer 106 provided on the electron transport layer 106. It has an electron injection layer 107 and a cathode 108 provided on the electron injection layer 107.

The organic electroluminescent element 100 is manufactured in the reverse order, for example, the substrate 101, the cathode 108 provided on the substrate 101, the electron injection layer 107 provided on the cathode 108, and the electron injection layer. The electron transport layer 106 provided on the 107, the light emitting layer 105 provided on the electron transport layer 106, the hole transport layer 104 provided on the light emitting layer 105, and the hole transport layer 104. The structure may include a hole injection layer 103 provided above and an anode 102 provided above the hole injection layer 103.

Not all of the above layers are required, and the minimum structural unit is composed of the anode 102, the light emitting layer 105, and the cathode 108, and the hole injection layer 103, the hole transport layer 104, the electron transport layer 106, and the electron injection. The layer 107 is an arbitrarily provided layer. Further, each of the above layers may be composed of a single layer or a plurality of layers.

As the mode of the layer constituting the organic electric field light emitting element, in addition to the above-described "board / anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode" configuration mode, "Substrate / anode / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode", "board / anode / hole injection layer / light emitting layer / electron transport layer / electron injection layer / cathode", "board / Anofect / hole injection layer / hole transport layer / light emitting layer / electron injection layer / cathode "," substrate / anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / cathode "," substrate / Anofect / light emitting layer / electron transport layer / electron injection layer / cathode "," substrate / anode / hole transport layer / light emitting layer / electron injection layer / cathode "," substrate / anode / hole transport layer / light emitting layer / "Electron transport layer / cathode", "Substrate / anode / hole injection layer / light emitting layer / electron injection layer / cathode", "board / anode / hole injection layer / light emitting layer / electron transport layer / cathode", "board / substrate / The configuration may be "anode / light emitting layer / electron transport layer / cathode" or "substrate / anode / light emitting layer / electron injection layer / cathode".

<Substrate in organic electroluminescent device>
The substrate 101 is a support for the organic electroluminescent element 100, and usually quartz, glass, metal, plastic, or the like is used. The substrate 101 is formed in a plate shape, a film shape, or a sheet shape depending on the purpose, and for example, a glass plate, a metal plate, a metal foil, a plastic film, a plastic sheet, or the like is used. Of these, a glass plate and a plate made of a transparent synthetic resin such as polyester, polymethacrylate, polycarbonate, and polysulfone are preferable. As for the glass substrate, soda lime glass, non-alkali glass, or the like is used, and the thickness may be sufficient to maintain the mechanical strength. Therefore, for example, 0.2 mm or more may be used. The upper limit of the thickness is, for example, 2 mm or less, preferably 1 mm or less. As for the material of the glass, non-alkali glass is preferable because it is better that there are few elution ions from the glass, but soda lime glass with a barrier coat such as SiO ₂ is also commercially available, so it is possible to use this. it can. Further, in order to enhance the gas barrier property, the substrate 101 may be provided with a gas barrier film such as a dense silicon oxide film on at least one side, and a synthetic resin plate, film or sheet having a particularly low gas barrier property may be used as the substrate 101. When used, it is preferable to provide a gas barrier film.

<Anode in organic electroluminescent device>
The anode 102 serves to inject holes into the light emitting layer 105. When the hole injection layer 103 and / or the hole transport layer 104 is provided between the anode 102 and the light emitting layer 105, holes are injected into the light emitting layer 105 through these. ..

Examples of the material forming the anode 102 include an inorganic compound and an organic compound. Examples of the inorganic compound include metals (aluminum, gold, silver, nickel, palladium, chromium, etc.), metal oxides (indium oxide, tin oxide, indium-tin oxide (ITO), indium-zinc oxidation, etc.). (IZO, etc.), metals halide (copper iodide, etc.), copper sulfide, carbon black, ITO glass, nesa glass, etc. Examples of the organic compound include polythiophene such as poly (3-methylthiophene) and conductive polymers such as polypyrrole and polyaniline. In addition, it can be appropriately selected and used from the substances used as the anode of the organic electroluminescent device.

The resistance of the transparent electrode is not limited as long as a sufficient current can be supplied to emit light from the light emitting element, but it is desirable that the resistance is low from the viewpoint of power consumption of the light emitting element. For example, an ITO substrate of 300 Ω / □ or less functions as an element electrode, but since it is now possible to supply a substrate of about 10 Ω / □, for example, 100 to 5 Ω / □, preferably 50 to 5 Ω. It is especially desirable to use a low resistance product of / □. The thickness of ITO can be arbitrarily selected according to the resistance value, but it is usually used in the range of 50 to 300 nm.

<Hole injection layer and hole transport layer in organic electroluminescent devices>
The hole injection layer 103 plays a role of efficiently injecting holes moving from the anode 102 into the light emitting layer 105 or the hole transport layer 104. The hole transport layer 104 plays a role of efficiently transporting holes injected from the anode 102 or holes injected from the anode 102 via the hole injection layer 103 to the light emitting layer 105. The hole injection layer 103 and the hole transport layer 104 are formed by laminating and mixing one or more of the hole injection / transport materials or a mixture of the hole injection / transport material and the polymer binder, respectively. Will be done. Further, an inorganic salt such as iron (III) chloride may be added to the hole injection / transport material to form a layer.

As a hole injection / transporting substance, it is necessary to efficiently inject / transport holes from the positive electrode between electrodes to which an electric field is applied, and the hole injection efficiency is high, and the injected holes are efficiently transported. It is desirable to do. For that purpose, it is preferable that the substance has a small ionization potential, a large hole mobility, excellent stability, and is less likely to generate trap impurities during production and use.

As the material for forming the hole injection layer 103 and the hole transport layer 104, the dimer compound according to the present invention can be used. Further, among photoconductive materials, among known compounds used in compounds conventionally used as hole charge transport materials, p-type semiconductors, hole injection layers and hole transport layers of organic electroluminescent devices. Any compound can be selected and used from. Specific examples thereof include carbazole derivatives (N-phenylcarbazole, polyvinylcarbazole, etc.), biscarbazole derivatives such as bis (N-arylcarbazole) or bis (N-alkylcarbazole), and triarylamine derivatives (aromatic tertiary). Polymers with amino in the main or side chains, 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane, N, N'-diphenyl-N, N'-di (3-methylphenyl) -4 , 4'-diaminobiphenyl, N, N'-diphenyl-N, N'-dinaphthyl-4,4'-diaminobiphenyl, N, N'-diphenyl-N, N'-di (3-methylphenyl) -4 , 4'-diphenyl-1,1'-diamine, N, N'-dinaphthyl -N, ^{N'-diphenyl-4,4'-diphenyl-1,1'-diamine, N} 4, N ^{4 '-} diphenyl - N ^4, N ^{4 '-} bis (9-phenyl -9H- carbazol-3-yl) - [1,1'-biphenyl] ^{-4,4'-diamine, N 4, N 4, N} 4', N 4 ^' -Tetra [1,1'-biphenyl] -4-yl)-[1,1'-biphenyl] -4,4'-diamine, 4,4', 4 "-tris (3-methylphenyl (phenyl) Triphenylamine derivatives such as amino) triphenylamine, starburstamine derivatives, etc.), stillben derivatives, phthalocyanine derivatives (metal-free, copper phthalocyanine, etc.), pyrazoline derivatives, hydrazone compounds, benzofuran derivatives, thiophene derivatives, oxadiazole derivatives , Kinoxalin derivatives (eg, 1,4,5,8,9,12-hexazatriphenylene-2,3,6,7,10,11-hexacarbonitrile, etc.), heterocyclic compounds such as porphyrin derivatives, polysilanes, etc. In the polymer system, polycarbonate or styrene derivative having the monomer as a side chain, polyvinylcarbazole, polysilane, or the like is preferable, but a thin film necessary for producing a light emitting element can be formed and holes can be injected from the anode. Further, the compound is not particularly limited as long as it can transport holes.

It is also known that the conductivity of organic semiconductors is strongly affected by its doping. Such an organic semiconductor matrix substance is composed of a compound having a good electron donating property or a compound having a good electron accepting property. Strong electron acceptors such as tetracyanoquinone dimethane (TCNQ) or 2,3,5,6-tetrafluorotetracyano-1,4-benzoquinone dimethane (F4TCNQ) are known for doping electron donors. (For example, the document "M.Pfeiffer, A.Beyer, T.Fritz, K.Leo, Appl.Phys.Lett., 73 (22), 3202-3204 (1998)" and the document "J. Blochwitz, M." See .Pheiffer, T.Fritz, K.Leo, Appl.Phys.Lett., 73 (6), 729-731 (1998) "). They generate so-called holes by an electron transfer process in an electron donating base material (hole transport material). Depending on the number of holes and the mobility, the conductivity of the base material changes considerably. As the matrix substance having hole transporting properties, for example, a benzidine derivative (TPD or the like) or a starburst amine derivative (TDATA or the like), or a specific metal phthalocyanine (particularly, zinc phthalocyanine (ZnPc) or the like) is known (such as zinc phthalocyanine). Japanese Unexamined Patent Publication No. 2005-167175).

<Light emitting layer in organic electroluminescent device>
The light emitting layer 105 is a layer that emits light by recombining the holes injected from the anode 102 and the electrons injected from the cathode 108 between the electrodes to which an electric field is applied. The material for forming the light emitting layer 105 may be a compound (light emitting compound) that is excited by recombination of holes and electrons to emit light, and can form a stable thin film shape and is in a solid state. It is preferable that the compound exhibits a strong emission (fluorescence) efficiency. In the present invention, the dimer compound according to the present invention can be used as the material for the light emitting layer.

The light emitting layer may be either a single layer or a plurality of layers, and each is formed of a light emitting layer material (host material, dopant material). The host material and the dopant material may be one type or a plurality of combinations. The dopant material may be included entirely, partially, or partially in the host material. As a doping method, it can be formed by a co-evaporation method with a host material, but it may be mixed with the host material in advance and then vapor-deposited at the same time.

The amount of the host material used depends on the type of host material and may be determined according to the characteristics of the host material. The guideline for the amount of the host material used is preferably 50 to 99.99% by weight, more preferably 80 to 99.95% by weight, and further preferably 90 to 99.9% by weight of the entire light emitting layer material. Is. The dimer compound according to the present invention can also be used as a host material.

The amount of the dopant material used varies depending on the type of the dopant material, and may be determined according to the characteristics of the dopant material. The guideline for the amount of the dopant used is preferably 0.001 to 50% by weight, more preferably 0.05 to 20% by weight, still more preferably 0.1 to 10% by weight of the entire light emitting layer material. is there. The above range is preferable in that, for example, the density quenching phenomenon can be prevented. The dimer compound according to the present invention can also be used as a dopant material.

Host materials that can be used in combination with the dimer compound according to the present invention include fused ring derivatives such as anthracene and pyrene, which have long been known as luminescent materials, and bisstyryl derivatives such as bisstyrylanthracene derivatives and distyrylbenzene derivatives. , Tetraphenylbutadiene derivative, cyclopentadiene derivative, fluorene derivative, benzofluorene derivative and the like.

Further, the dopant material that can be used in combination with the dimer compound according to the present invention is not particularly limited, and a known compound can be used, and it is selected from various materials according to a desired emission color. be able to. Specifically, for example, fused ring derivatives such as phenanthrene, anthracene, pyrene, tetracene, pentacene, perylene, naphthopylene, dibenzopyrene, rubrene and chrysen, benzoxazole derivatives, benzothiazole derivatives, benzoimidazole derivatives, benzotriazole derivatives, oxazoles. Bistylyl derivatives such as derivatives, oxadiazol derivatives, thiazole derivatives, imidazole derivatives, thiadiazol derivatives, triazole derivatives, pyrazoline derivatives, stillben derivatives, thiophene derivatives, tetraphenylbutadiene derivatives, cyclopentadiene derivatives, bisstyrylanthracene derivatives and distyrylbenzene derivatives. (Japanese Patent Laid-Open No. 1-245087), bisstyrylallylene derivative (Japanese Patent Laid-Open No. 2-247278), diazaindacene derivative, furan derivative, benzofuran derivative, phenylisobenzofuran, dimesitylisobenzofuran, di (2-methylphenyl) Isobenzofuran derivatives such as isobenzofuran, di (2-trifluoromethylphenyl) isobenzofuran, phenylisobenzofuran, dibenzofuran derivatives, 7-dialkylaminocoumarin derivatives, 7-piperidinocoumarin derivatives, 7-hydroxycoumarin derivatives, 7- Cumarin derivatives such as methoxycoumarin derivatives, 7-acetoxycoumarin derivatives, 3-benzothiazolylcoumarin derivatives, 3-benzoimidazolylcoumarin derivatives, 3-benzoxazolylcoumarin derivatives, dicyanomethylenepyran derivatives, dicyanomethylenethiopyran derivatives, polymethine Derivatives, cyanine derivatives, oxobenzoanthracene derivatives, xanthene derivatives, rhodamine derivatives, fluorescein derivatives, pyrylium derivatives, carbostyryl derivatives, acrydin derivatives, oxazine derivatives, phenylene oxide derivatives, quinacridone derivatives, quinazoline derivatives, pyrolopyridine derivatives, flopyridine derivatives, Examples thereof include 1,2,5-thiadiazolopylene derivatives, pyromethene derivatives, perinone derivatives, pyrolopyrrole derivatives, squarylium derivatives, biolantron derivatives, phenazine derivatives, acridone derivatives, deazaflavin derivatives, fluorene derivatives and benzofluorene derivatives.

For example, as blue to blue-green dopant materials for each coloring light, aromatic hydrocarbon compounds such as naphthalene, anthracene, phenanthrene, pyrene, triphenylene, perylene, fluorene, inden, and chrysen and their derivatives, furan, pyrrole, thiophene, etc. Aromatic complexes such as silol, 9-silafluolene, 9,9'-spirobicilafluorene, benzothiophene, benzofuran, indol, dibenzothiophene, dibenzofuran, imidazopyridine, phenanthroline, pyrazine, naphthylidine, quinoxalin, pyrolopyridine, thioxanthene. Ring compounds and their derivatives, distyrylbenzene derivatives, tetraphenylbutadiene derivatives, stillben derivatives, aldazine derivatives, coumarin derivatives, imidazole, thiazole, thiadiazol, carbazole, oxazole, oxadiazol, triazole and other azole derivatives and their metal complexes and N , N'-diphenyl-N, N'-di (3-methylphenyl) -4,4'-diphenyl-1,1'-diamine and other aromatic amine derivatives.

Examples of the green to yellow dopant material include coumarin derivatives, phthalimide derivatives, naphthalimide derivatives, perinone derivatives, pyrrolopyrrole derivatives, cyclopentadiene derivatives, acridone derivatives, quinacridone derivatives, naphthacene derivatives such as rubrene, and the above blue. A preferable example is a compound in which a substituent capable of lengthening the wavelength, such as aryl, heteroaryl, arylvinyl, amino, and cyano, is introduced into the compound exemplified as the blue-green dopant material.

Further, as the orange to red dopant material, naphthalimide derivatives such as bis (diisopropylphenyl) perylenetetracarboxylic acid imide, perinone derivatives, rare earth complexes such as Eu complex having acetylacetone, benzoylacetone and phenanthroline as ligands, 4 -(Dicyanomethylene) -2-methyl-6- (p-dimethylaminostyryl) -4H-pyran and its analogs, metal phthalocyanine derivatives such as magnesium phthalocyanine and aluminum chlorophthalocyanine, rhodamine compounds, deazaflavin derivatives, coumarin derivatives, quinacridone Derivatives, phenoxazine derivatives, oxazine derivatives, quinazoline derivatives, pyrolopyridine derivatives, squarylium derivatives, biolantron derivatives, phenazine derivatives, phenoxazone derivatives, thiadiazolopyrene derivatives and the like, and further exemplified as the above-mentioned blue-blue-green and green-yellow dopant materials. A preferable example is a compound in which a substituent capable of lengthening the wavelength, such as aryl, heteroaryl, arylvinyl, amino, and cyano, is introduced into the above-mentioned compound.

In addition, as the dopant, it can be appropriately selected and used from the compounds described in the June 2004 issue of Chemical Industry, page 13, and the references mentioned therein.

Among the above-mentioned dopant materials, amines, perylene derivatives, borane derivatives, aromatic amine derivatives, coumarin derivatives, pyrane derivatives or pyrene derivatives having a stillben structure are particularly preferable.

An amine having a stilbene structure is represented by, for example, the following formula.
In the formula, Ar ¹ is an m-valent group derived from an aryl having 6 to 30 carbon atoms, and Ar ² and Ar ³ are independently aryls having 6 to 30 carbon atoms, but Ar ^{1 to} Ar. ^At least one of ³ has a stillben structure, Ar ^{1 to} Ar ³ may be substituted, and m is an integer of 1 to 4.

The amine having a stilbene structure is more preferably diaminostilbene represented by the following formula.
In the formula, Ar ² and Ar ³ are independently aryls having 6 to 30 carbon atoms, and Ar ² and Ar ³ may be substituted.

Specific examples of aryls having 6 to 30 carbon atoms are benzene, naphthalene, acenaphthylene, fluorene, phenalene, phenanthrene, anthracene, fluorene, triphenylene, pyrene, chrysene, naphthalene, perylene, stilben, distyrylbenzene, distyrylbiphenyl, and distyryl. Fluorene and the like can be mentioned.

Specific examples of amines having a stilbene structure are N, N, N', N'-tetra (4-biphenylyl) -4,4'-diaminostilbene, N, N, N', N'-tetra (1-naphthyl). ) -4,4'-diaminostilbene, N, N, N', N'-tetra (2-naphthyl) -4,4'-diaminostilbene, N, N'-di (2-naphthyl) -N, N '-Diphenyl-4,4'-diaminostilbene, N, N'-di (9-phenanthryl) -N, N'-diphenyl-4,4'-diaminostilbene, 4,4'-bis [4 "-bis (Diphenylamino) stilbene] -biphenyl, 1,4-bis [4'-bis (diphenylamino) stilbene] -benzene, 2,7-bis [4'-bis (diphenylamino) stilbene] -9,9-dimethyl Examples thereof include fluorene, 4,4'-bis (9-ethyl-3-carbazobinylene) -biphenyl, 4,4'-bis (9-phenyl-3-carbazovinylene) -biphenyl and the like.
Further, amines having a stilbene structure described in JP-A-2003-347056 and JP-A-2001-307884 may be used.

Examples of the perylene derivative include 3,10-bis (2,6-dimethylphenyl) perylene, 3,10-bis (2,4,6-trimethylphenyl) perylene, 3,10-diphenylperylene, and 3,4-. Diphenylperylene, 2,5,8,11-tetra-t-butylperylene, 3,4,9,10-tetraphenylperylene, 3- (1'-pyrenyl) -8,11-di (t-butyl) perylene , 3- (9'-anthril) -8,11-di (t-butyl) perylene, 3,3'-bis (8,11-di (t-butyl) perylenel) and the like.
In addition, JP-A-11-97178, JP-A-2000-133457, JP-A-2000-26324, JP-A-2001-267079, JP-A-2001-267078, JP-A-2001-267076, Perylene derivatives described in JP-A-2000-34234, JP-A-2001-267075, JP-A-2001-217077, and the like may be used.

Examples of the borane derivative include 1,8-diphenyl-10- (dimethylboryl) anthracene, 9-phenyl-10- (dimethylboryl) anthracene, 4- (9'-anthril) dimethylborylnaphthalene, 4- (10'). -Phenyl-9'-anthryl) dimesitylborylnaphthalene, 9- (dimesitylboryl) anthracene, 9- (4'-biphenylyl) -10- (dimesitylboryl) anthracene, 9- (4'-(N-carbazolyl) phenyl) -10- (Dimethylboryl) Anthracene and the like can be mentioned.
Further, the borane derivative described in International Publication No. 2000/40586 pamphlet or the like may be used.

The aromatic amine derivative is represented by, for example, the following formula.
In the formula, Ar ⁴ is an n-valent group derived from a aryl having 6 to 30 carbon atoms, Ar ⁵ and Ar ⁶ are each independently an aryl having 6 to 30 carbon ^atoms, Ar 4 to Ar ⁶ is It may be substituted and n is an integer of 1-4.

In particular, a divalent group Ar ⁴ is derived from anthracene, chrysene, fluorene, benzo fluorene or pyrene, Ar ⁵ and Ar ⁶ are each independently an aryl having 6 to 30 carbon ^atoms, Ar 4 to Ar ⁶ May be substituted, and n is 2, aromatic amine derivatives are more preferred.

Specific examples of aryls having 6 to 30 carbon atoms include benzene, naphthalene, acenaphthylene, fluorene, phenalene, phenanthrene, anthracene, fluoranthene, triphenylene, pyrene, chrysen, naphthalene, perylene and pentacene.

As the aromatic amine derivative, as a chrysen system, for example, N, N, N', N'-tetraphenylcrisen-6,12-diamine, N, N, N', N'-tetra (p-tolyl) Chrysen-6,12-diamine, N, N, N', N'-tetra (m-tolyl) Chrysen-6,12-diamine, N, N, N', N'-tetrakis (4-isopropylphenyl) chrysen -6,12-diamine, N, N, N', N'-tetra (naphthalen-2-yl) chrysen-6,12-diamine, N, N'-diphenyl-N, N'-di (p-tolyl) ) Chrysen-6,12-diamine, N, N'-diphenyl-N, N'-bis (4-ethylphenyl) Chrysen-6,12-diamine, N, N'-diphenyl-N, N'-bis ( 4-Ethylphenyl) chrysene-6,12-diamine, N, N'-diphenyl-N, N'-bis (4-isopropylphenyl) chrysen-6,12-diamine, N, N'-diphenyl-N, N '-Bis (4-t-butylphenyl) chrysen-6,12-diamine, N, N'-bis (4-isopropylphenyl) -N, N'-di (p-tolyl) chrysen-6,12-diamine And so on.

As the pyrene system, for example, N, N, N', N'-tetraphenylpyrene-1,6-diamine, N, N, N', N'-tetra (p-tolyl) pyrene-1,6 -Diamine, N, N, N', N'-tetra (m-tolyl) pyrene-1,6-diamine, N, N, N', N'-tetrakis (4-isopropylphenyl) pyrene-1,6- Diamine, N, N, N', N'-tetrakis (3,4-dimethylphenyl) pyrene-1,6-diamine, N, N'-diphenyl-N, N'-di (p-tolyl) pyrene-1 , 6-Diamine, N, N'-diphenyl-N, N'-bis (4-ethylphenyl) pyrene-1,6-diamine, N, N'-diphenyl-N, N'-bis (4-ethylphenyl) ) Pyrene-1,6-diamine, N, N'-diphenyl-N, N'-bis (4-isopropylphenyl) Pyrene-1,6-diamine, N, N'-diphenyl-N, N'-bis ( 4-t-butylphenyl) pyrene-1,6-diamine, N, N'-bis (4-isopropylphenyl) -N, N'-di (p-tolyl) pyrene-1,6-diamine, N, N , N', N'-tetrakis (3,4-dimethylphenyl) -3,8-diphenylpyrene-1,6-diamine, N, N, N, N-tetraphenylpyrene-1,8-diamine, N, N'-bis (biphenyl-4-yl) -N, N'-diphenylpyrene-1,8-diamine, N ¹ , N ⁶ -diphenyl-N ¹ , N ⁶ -bis- (4-trimethylsilanyl-phenyl) ) -1H, 8H-pyrene-1,6-diamine and the like.

The anthracene system includes, for example, N, N, N, N-tetraphenylanthracene-9,10-diamine, N, N, N', N'-tetra (p-tolyl) anthracene-9,10-diamine. , N, N, N', N'-tetra (m-tolyl) anthracene-9,10-diamine, N, N, N', N'-tetrakis (4-isopropylphenyl) anthracene-9,10-diamine, N, N'-diphenyl-N, N'-di (p-tolyl) anthracene-9,10-diamine, N, N'-diphenyl-N, N'-di (m-tolyl) anthracene-9,10- Diamine, N, N'-diphenyl-N, N'-bis (4-ethylphenyl) anthracene-9,10-diamine, N, N'-diphenyl-N, N'-bis (4-ethylphenyl) anthracene- 9,10-diamine, N, N'-diphenyl-N, N'-bis (4-isopropylphenyl) anthracene-9,10-diamine, N, N'-diphenyl-N, N'-bis (4-t) -Butylphenyl) anthracene-9,10-diamine, N, N'-bis (4-isopropylphenyl) -N, N'-di (p-tolyl) anthracene-9,10-diamine, 2,6-di- t-butyl-N, N, N', N'-tetra (p-tolyl) anthracene-9,10-diamine, 2,6-di-t-butyl-N, N'-diphenyl-N, N'- Bis (4-isopropylphenyl) anthracene-9,10-diamine, 2,6-di-t-butyl-N, N'-bis (4-isopropylphenyl) -N, N'-di (p-tolyl) anthracene -9,10-diamine, 2,6-dicyclohexyl-N, N'-bis (4-isopropylphenyl) -N, N'-di (p-tolyl) anthracene-9,10-diamine, 2,6-dicyclohexyl -N, N'-bis (4-isopropylphenyl) -N, N'-bis (4-t-butylphenyl) anthracene-9,10-diamine, 9,10-bis (4-diphenylamino-phenyl) anthracene , 9,10-bis (4-di (1-naphthylamino) phenyl) anthracene, 9,10-bis (4-di (2-naphthylamino) phenyl) anthracene, 10-di-p-tolylamino-9-( 4-di-p-tolylamino-1-naphthyl) anthracene, 10-diphenylamino-9- (4-diphenylamino-1-naphthyl) anthracene, 10-diphenylamino- Examples thereof include 9- (6-diphenylamino-2-naphthyl) anthracene.

In addition, [4- (4-diphenylamino-phenyl) naphthalene-1-yl] -diphenylamine, [6- (4-diphenylamino-phenyl) naphthalene-2-yl] -diphenylamine, 4,4'. -Bis [4-diphenylaminonaphthalene-1-yl] biphenyl, 4,4'-bis [6-diphenylaminonaphthalen-2-yl] biphenyl, 4,4 "-bis [4-diphenylaminonaphthalen-1-yl] ] -P-Terphenyl, 4,4 "-bis [6-diphenylaminonaphthalen-2-yl] -p-terphenyl and the like.
Further, the aromatic amine derivative described in JP-A-2006-156888 may be used.

Examples of the coumarin derivative include coumarin-6 and coumarin-334.
Further, the coumarin derivatives described in JP-A-2004-43646, JP-A-2001-76876, JP-A-6-298758 and the like may be used.

Examples of the pyran derivative include the following DCM and DCJTB.
Further, JP-A-2005-126399, JP-A-2005-097283, JP-A-2002-234892, JP-A-2001-220577, JP-A-2001-081090, and JP-A-2001-052869. The pyran derivative described in the above may be used.

<Electronic injection layer and electron transport layer in organic electroluminescent device>
The electron injection layer 107 plays a role of efficiently injecting electrons moving from the cathode 108 into the light emitting layer 105 or the electron transport layer 106. The electron transport layer 106 plays a role of efficiently transporting the electrons injected from the cathode 108 or the electrons injected from the cathode 108 via the electron injection layer 107 to the light emitting layer 105. The electron transport layer 106 and the electron injection layer 107 are formed by laminating and mixing one or more kinds of electron transport / injection materials or a mixture of the electron transport / injection material and the polymer binder, respectively.

The electron injection / transport layer is a layer in which electrons are injected from the cathode and is in charge of transporting the electrons, and it is desirable that the electron injection efficiency is high and the injected electrons are efficiently transported. For that purpose, it is preferable that the substance has a large electron affinity, a high electron mobility, excellent stability, and is less likely to generate impurities as traps during production and use. However, when considering the transport balance between holes and electrons, the electron transport capacity is so high when it mainly plays a role of efficiently blocking the holes from the anode from flowing to the cathode side without recombination. Even if it is not high, it has the same effect of improving luminous efficiency as a material having high electron transport capacity. Therefore, the electron injection / transport layer in the present embodiment may also include the function of a layer capable of efficiently blocking the movement of holes.

As the material (electron transport material) for forming the electron transport layer 106 or the electron injection layer 107, the dimer compound according to the present invention can be used. Further, it can be arbitrarily selected and used from a compound conventionally used as an electron transfer compound in a photoconductive material, a known compound used for an electron injection layer and an electron transport layer of an organic electroluminescent element. ..

Materials used for the electron transport layer or electron injection layer are compounds composed of aromatic rings or heteroaromatic rings composed of one or more atoms selected from carbon, hydrogen, oxygen, sulfur, silicon and phosphorus, and pyrrole derivatives. It is preferable to contain at least one selected from the condensed ring derivative thereof and a metal complex having an electron-accepting nitrogen. Specifically, fused ring-based aromatic ring derivatives such as naphthalene and anthracene, styryl-based aromatic ring derivatives typified by 4,4'-bis (diphenylethenyl) biphenyl, perinone derivatives, coumarin derivatives, naphthalimide derivatives, anthraquinones. And quinone derivatives such as diphenoquinone, phosphoroxide derivatives, carbazole derivatives and indole derivatives. Examples of the metal complex having electron-accepting nitrogen include hydroxyazole complexes such as hydroxyphenyloxazole complex, azomethine complex, tropolone metal complex, flavonol metal complex and benzoquinoline metal complex. These materials may be used alone, but may be mixed with different materials.

Specific examples of other electron transfer compounds include pyridine derivatives, naphthalene derivatives, anthracene derivatives, phenanthroline derivatives, perinone derivatives, coumarin derivatives, naphthalimide derivatives, anthraquinone derivatives, diphenoquinone derivatives, diphenylquinone derivatives, perylene derivatives, and oxadiasols. Derivatives (1,3-bis [(4-t-butylphenyl) 1,3,4-oxadiazolyl] phenylene, etc.), thiophene derivatives, triazole derivatives (N-naphthyl-2,5-diphenyl-1,3,4- Triazole, etc.), thiazazole derivatives, oxine derivative metal complexes, quinolinol-based metal complexes, quinoxalin derivatives, quinoxalin derivative polymers, benzazole compounds, gallium complexes, pyrazole derivatives, perfluorophenylene derivatives, triazine derivatives, pyrazine derivatives, benzoquinoline Derivatives (2,2'-bis (benzo [h] quinoline-2-yl) -9,9'-spirobifluorene, etc.), imidazole pyridine derivatives, borane derivatives, benzoimidazole derivatives (tris (N-phenylbenzoimidazole-) 2-yl) benzene, etc.), benzoxazole derivatives, benzothiazole derivatives, quinoline derivatives, oligopyridine derivatives such as telpyridine, bipyridine derivatives, telpyridine derivatives (1,3-bis (4'-(2,2': 6'2)) "-Terpyridinyl)) benzene, etc.), naphthylidine derivatives (bis (1-naphthyl) -4- (1,8-naphthylidine-2-yl) phenylphosphine oxide, etc.), aldazine derivatives, carbazole derivatives, indol derivatives, phosphoroxide derivatives , Bistylyl derivatives and the like.

Further, a metal complex having electron-accepting nitrogen can also be used. For example, hydroxyazole complexes such as quinolinol-based metal complexes and hydroxyphenyloxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes and benzoquinoline metal complexes can be used. can give.

The above-mentioned materials may be used alone, but may be mixed with different materials.

Among the above-mentioned materials, quinolinol-based metal complexes, bipyridine derivatives, phenanthroline derivatives or borane derivatives are preferable.

The quinolinol-based metal complex is a compound represented by the following general formula (E-1).
In the formula, R ^{1 to} R ⁶ are hydrogens or substituents, M is Li, Al, Ga, Be or Zn, and n is an integer of 1-3.

Specific examples of the quinolinol-based metal complex include 8-quinolinol lithium, tris (8-quinolinolate) aluminum, tris (4-methyl-8-quinolinolate) aluminum, tris (5-methyl-8-quinolinolate) aluminum, and tris (3). , 4-Dimethyl-8-quinolinolate) aluminum, tris (4,5-dimethyl-8-quinolinolate) aluminum, tris (4,5-dimethyl-8-quinolinolate) aluminum, bis (2-methyl-8-quinolinolate) ( Phenolate) Aluminum, bis (2-methyl-8-quinolinolate) (2-methylphenolate) aluminum, bis (2-methyl-8-quinolinolate) (3-methylphenorate) aluminum, bis (2-methyl-8- Kinolinolate) (4-methylphenorate) aluminum, bis (2-methyl-8-quinolinolate) (2-phenylphenolate) aluminum, bis (2-methyl-8-quinolinolate) (3-phenylphenolate) aluminum, bis (2-Methyl-8-quinolinolate) (4-phenylphenolate) aluminum, bis (2-methyl-8-quinolinolate) (2,3-dimethylphenolate) aluminum, bis (2-methyl-8-quinolinolate) ( 2,6-Dimethylphenolate) Aluminum, bis (2-methyl-8-quinolinolate) (3,4-dimethylphenolate) Aluminum, bis (2-methyl-8-quinolinolate) (3,5-dimethylphenolate) Aluminum, bis (2-methyl-8-quinolinolate) (3,5-di-t-butylphenolate) Aluminum, bis (2-methyl-8-quinolinolate) (2,6-diphenylphenolate) Aluminum, bis ( 2-Methyl-8-quinolinolate) (2,4,6-triphenylphenolate) aluminum, bis (2-methyl-8-quinolinolate) (2,4,6-trimethylphenolate) aluminum, bis (2-methyl -8-quinolinolate) (2,4,5,6-tetramethylphenorate) aluminum, bis (2-methyl-8-quinolinolate) (1-naphtholate) aluminum, bis (2-methyl-8-quinolinolate) (2) -Naftrat) Aluminum, bis (2,4-dimethyl-8-quinolinolate) (2-phenylphenylate) Aluminum, bis (2,4-dimethyl-8-quinolinolate) ) (3-phenylphenolate) aluminum, bis (2,4-dimethyl-8-quinolinolate) (4-phenylphenolate) aluminum, bis (2,4-dimethyl-8-quinolinolate) (3,5-dimethylphenolate) Lat) Aluminum, bis (2,4-dimethyl-8-quinolinolate) (3,5-di-t-butylphenolate) aluminum, bis (2-methyl-8-quinolinolate) aluminum-μ-oxo-bis (2) -Methyl-8-quinolinolate) aluminum, bis (2,4-dimethyl-8-quinolinolate) aluminum-μ-oxo-bis (2,4-dimethyl-8-quinolinolate) aluminum, bis (2-methyl-4-ethyl) -8-Kinolinolate) Aluminum-μ-oxo-bis (2-methyl-4-ethyl-8-quinolinolate) Aluminum, bis (2-methyl-4-methoxy-8-quinolinolate) Aluminum-μ-oxo-bis (2) -Methyl-4-methoxy-8-quinolinolate) aluminum, bis (2-methyl-5-cyano-8-quinolinolate) aluminum-μ-oxo-bis (2-methyl-5-cyano-8-quinolinolate) aluminum, bis (2-Methyl-5-trifluoromethyl-8-quinolinolate) Aluminum-μ-oxo-bis (2-methyl-5-trifluoromethyl-8-quinolinolate) Aluminum, bis (10-hydroxybenzo [h] quinolinate) Berylium and the like can be mentioned.

The bipyridine derivative is a compound represented by the following general formula (E-2).
In the formula, G represents a mere bond or n-valent linking group, and n is an integer of 2-8. Further, carbons not used for the bond of pyridine-pyridine or pyridine-G may be substituted.

Examples of G in the general formula (E-2) include the following structural formulas. In addition, R in the following structural formula is independently hydrogen, methyl, ethyl, isopropyl, cyclohexyl, phenyl, 1-naphthyl, 2-naphthyl, biphenylyl or terphenylyl.

Specific examples of the pyridine derivative include 2,5-bis (2,2'-pyridine-6-yl) -1,1-dimethyl-3,4-diphenylsilol and 2,5-bis (2,2'-). Pyridine-6-yl) -1,1-dimethyl-3,4-dimesitylcilol, 2,5-bis (2,2'-pyridin-5-yl) -1,1-dimethyl-3,4- Diphenylsilol, 2,5-bis (2,2'-pyridin-5-yl) -1,1-dimethyl-3,4-dimesitylcilol, 9,10-di (2,2'-pyridin-6) -Il) anthracene, 9,10-di (2,2'-pyridin-5-yl) anthracene, 9,10-di (2,3'-pyridin-6-yl) anthracene, 9,10-di (2) , 3'-Pyridine-5-yl) anthracene, 9,10-di (2,3'-pyridin-6-yl) -2-phenylanthracene, 9,10-di (2,3'-pyridin-5-yl) Il) -2-phenylanthracene, 9,10-di (2,2'-pyridin-6-yl) -2-phenylanthracene, 9,10-di (2,2'-pyridin-5-yl) -2 -Phenylanthracene, 9,10-di (2,4'-pyridin-6-yl) -2-phenylanthracene, 9,10-di (2,4'-pyridin-5-yl) -2-phenylanthracene, 9,10-di (3,4'-pyridin-6-yl) -2-phenylanthracene, 9,10-di (3,4'-pyridin-5-yl) -2-phenylanthracene, 3,4- Diphenyl-2,5-di (2,2'-pyridin-6-yl) thiophene, 3,4-diphenyl-2,5-di (2,3'-pyridin-5-yl) thiophene, 6', 6 Examples thereof include "-di (2-pyridyl) 2,2': 4', 4": 2 ", 2"'-quaterpyridine and the like.

The phenanthroline derivative is a compound represented by the following general formula (E-3-1) or (E-3-2).
In the formula, R ^{1 to} R ⁸ are hydrogen or substituents, adjacent groups may bond to each other to form a condensation ring, G represents a simple bond or n-valent linking group, and n is 2. It is an integer of ~ 8. Further, as G of the general formula (E-3-2), for example, the same structural formula as G described in the column of bipyridine derivative can be mentioned.

Specific examples of the phenanthroline derivative include 4,7-diphenyl-1,10-phenanthroline, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, 9,10-di (1,10-phenanthroline-). 2-yl) anthracene, 2,6-di (1,10-phenanthroline-5-yl) pyridine, 1,3,5-tri (1,10-phenanthroline-5-yl) benzene, 9,9'-difluol Examples thereof include −bis (1,10-phenanthroline-5-yl), vasocproin and 1,3-bis (2-phenyl-1,10-phenanthroline-9-yl) benzene.

In particular, a case where the phenanthroline derivative is used for the electron transport layer and the electron injection layer will be described. In order to obtain stable light emission over a long period of time, a material having excellent thermal stability and thin film forming property is desired. Among the phenanthroline derivatives, the substituent itself has a three-dimensional three-dimensional structure, or the phenanthroline skeleton or A derivative having a three-dimensional three-dimensional structure due to steric repulsion with an adjacent substituent or a derivative in which a plurality of phenanthroline skeletons are linked is preferable. Furthermore, when connecting a plurality of phenanthroline skeletons, a compound containing a conjugated bond, a substituted or unsubstituted aromatic hydrocarbon, or a substituted or unsubstituted aromatic heterocycle in the linking unit is more preferable.

The borane derivative is a compound represented by the following general formula (E-4), and is disclosed in detail in JP-A-2007-27587.
In the formula, R ¹¹ and R ¹² are independently hydrogen, alkyl, cycloalkyl, optionally substituted aryl, substituted silyl, optionally substituted nitrogen-containing heterocycle, or cyano. At least one, R ^{13 to} R ¹⁶ are independently optionally substituted alkyl, optionally substituted cycloalkyl or optionally substituted aryl, and X is substituted. It is an arylene which may be optionally, Y is an aryl which may be substituted with 16 or less carbon atoms, a boron which is substituted, or a carbazolyl which may be substituted, and n is 0 independently of each other. It is an integer of ~ 3.

Among the compounds represented by the above general formula (E-4), the compounds represented by the following general formula (E-4-1), and further the following general formulas (E-4-1-1) to (E-4). The compound represented by -1--4) is preferable. Specific examples include 9- [4- (4-dimecitylborylnaphthalen-1-yl) phenyl] carbazole and 9- [4- (4-dimeshtylborylnaphthalen-1-yl) naphthalene-1-yl). ] Carbazole and the like can be mentioned.
In the formula, R ¹¹ and R ¹² are independently hydrogen, alkyl, cycloalkyl, optionally substituted aryl, substituted silyl, optionally substituted nitrogen-containing heterocycle, or cyano. At least one, R ^{13 to} R ¹⁶ are independently optionally substituted alkyl, optionally substituted cycloalkyl or optionally substituted aryl, R ²¹ and R ^{22 respectively.} Are each independently at least one of hydrogen, alkyl, cycloalkyl, optionally substituted aryl, substituted silyl, optionally substituted nitrogen-containing heterocycle, or cyano, X ¹ Is an arylene having 20 or less carbon atoms which may be substituted, n is an integer of 0 to 3 independently, and m is an integer of 0 to 4 independently.

In each formula, R ^{31 to} R ³⁴ are independently either methyl, isopropyl or phenyl, and R ³⁵ and R ³⁶ are independently either hydrogen, methyl, isopropyl or phenyl, respectively. Is it?

Among the compounds represented by the above general formula (E-4), the compound represented by the following general formula (E-4-2) and the compound represented by the following general formula (E-4-2-1). Is preferable.
In the formula, R ¹¹ and R ¹² are independently hydrogen, alkyl, cycloalkyl, optionally substituted aryl, substituted silyl, optionally substituted nitrogen-containing heterocycle, or cyano. At least one, R ^{13 to} R ¹⁶ are independently optionally substituted alkyl, optionally substituted cycloalkyl or optionally substituted aryl, and X ¹ is substituted. It is an arylene having 20 or less carbon atoms which may be used, and n is an independently integer of 0 to 3.

In the formula, R ^{31 to} R ³⁴ are independently either methyl, isopropyl or phenyl, and R ³⁵ and R ³⁶ are independently either hydrogen, methyl, isopropyl or phenyl, respectively. Is.

Among the compounds represented by the above general formula (E-4), the compound represented by the following general formula (E-4-3), and further the following general formula (E-4-3-1) or (E-4). The compound represented by -3-2) is preferable.
In the formula, R ¹¹ and R ¹² are independently hydrogen, alkyl, cycloalkyl, optionally substituted aryl, substituted silyl, optionally substituted nitrogen-containing heterocycle, or cyano. At least one, R ^{13 to} R ¹⁶ are independently optionally substituted alkyl, optionally substituted cycloalkyl or optionally substituted aryl, and X ¹ is substituted. arylene which may number 10 or fewer carbon have been, Y ¹ is an aryl follows carbon atoms 14 substituted, and, n represents each independently represents an integer of 0 to 3.

In each formula, R ^{31 to} R ³⁴ are independently either methyl, isopropyl or phenyl, and R ³⁵ and R ³⁶ are independently either hydrogen, methyl, isopropyl or phenyl, respectively. Is it?

The benzimidazole derivative is a compound represented by the following general formula (E-5).
In the formula, Ar ^{1 to} Ar ³ are each independently hydrogen or an aryl having 6 to 30 carbon atoms which may be substituted. In particular, a benzimidazole derivative, which is an anthril in which Ar ¹ may be substituted, is preferable.

Specific examples of aryls having 6 to 30 carbon atoms are phenyl, 1-naphthyl, 2-naphthyl, acenaphthylene-1-yl, acenaphthylene-3-yl, acenaphthylene-4-yl, acenaphthylene-5-yl, fluoranthene-1-yl. Il, fluoren-2-yl, fluoren-3-yl, fluoren-4-yl, fluoren-9-yl, phenalen-1-yl, phenalen-2-yl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-Phenantril, 9-Phenantril, 1-Anthril, 2-Anthril, 9-Anthril, Fluoranthene-1-yl, Fluoranthen-2-yl, Fluoranthene-3-yl, Fluoranthen-7-yl, Fluoranthene-8-yl, Triphenylene-1-yl, triphenylene-2-yl, pyrene-1-yl, pyrene-2-yl, pyrene-4-yl, chrysene-1-yl, chrysene-2-yl, chrysene-3-yl, chrysene- 4-yl, chrysene-5-yl, chrysene-6-yl, naphthacene-1-yl, naphthacene-2-yl, naphthacene-5-yl, perylene-1-yl, perylene-2-yl, perylene-3-yl Il, pentasen-1-yl, pentasen-2-yl, pentasen-5-yl, pentasen-6-yl.

Specific examples of the benzoimidazole derivative include 1-phenyl-2- (4- (10-phenylanthracene-9-yl) phenyl) -1H-benzo [d] imidazole, 2- (4- (10- (naphthalen-2) phenyl). -Il) anthracene-9-yl) phenyl) -1-phenyl-1H-benzo [d] imidazole, 2- (3- (10- (naphthalen-2-yl) anthracene-9-yl) phenyl) -1- Phenyl-1H-benzo [d] imidazole, 5- (10- (naphthalen-2-yl) anthracene-9-yl) -1,2-diphenyl-1H-benzo [d] imidazole, 1- (4- (10) -(Naphthalen-2-yl) anthracene-9-yl) phenyl) -2-phenyl-1H-benzo [d] imidazole, 2- (4- (9,10-di (naphthalen-2-yl) anthracene-2) -Il) phenyl) -1-phenyl-1H-benzo [d] imidazole, 1-(4- (9,10-di (naphthalen-2-yl) anthracene-2-yl) phenyl) -2-phenyl-1H -Benzo [d] imidazole, 5- (9,10-di (naphthalen-2-yl) anthracene-2-yl) -1,2-diphenyl-1H-benzo [d] imidazole.

The electron transport layer or the electron injection layer may further contain a substance capable of reducing the material forming the electron transport layer or the electron injection layer. As the reducing substance, various materials are used as long as they have a certain reducing property. For example, alkali metal, alkaline earth metal, rare earth metal, alkali metal oxide, alkali metal halide, alkali. From the group consisting of oxides of earth metals, halides of alkaline earth metals, oxides of rare earth metals, halides of rare earth metals, organic complexes of alkali metals, organic complexes of alkaline earth metals and organic complexes of rare earth metals. At least one selected can be preferably used.

Preferred reducing substances include alkali metals such as Na (work function 2.36 eV), K (2.28 eV), Rb (2.16 eV) or Cs (1.95 eV), and Ca (2.95 eV). Alkaline earth metals such as 9 eV), Sr (2.0 to 2.5 eV) or Ba (2.52 eV) are mentioned, and materials having a work function of 2.9 eV or less are particularly preferable. Of these, the more preferable reducing substance is an alkali metal of K, Rb or Cs, more preferably Rb or Cs, and most preferably Cs. These alkali metals have a particularly high reducing ability, and by adding a relatively small amount to the material forming the electron transport layer or the electron injection layer, the emission brightness and the life of the organic EL device can be extended. Further, as a reducing substance having a work function of 2.9 eV or less, a combination of these two or more kinds of alkali metals is also preferable, and in particular, a combination containing Cs, for example, Cs and Na, Cs and K, Cs and Rb, or A combination of Cs, Na and K is preferred. By containing Cs, the reducing ability can be efficiently exhibited, and by adding to the material forming the electron transport layer or the electron injection layer, the emission brightness and the life of the organic EL device can be improved.

<Cathode in organic electroluminescent device>
The cathode 108 serves to inject electrons into the light emitting layer 105 via the electron injecting layer 107 and the electron transporting layer 106.

The material for forming the cathode 108 is not particularly limited as long as it is a substance capable of efficiently injecting electrons into the organic layer, but a material similar to the material for forming the anode 102 can be used. Among them, metals such as tin, indium, calcium, aluminum, silver, copper, nickel, chromium, gold, platinum, iron, zinc, lithium, sodium, potassium, cesium and magnesium or their alloys (magnesium-silver alloy, magnesium). -Indium alloys, aluminum-lithium alloys such as lithium fluoride / aluminum, etc.) are preferred. Alloys containing lithium, sodium, potassium, cesium, calcium, magnesium or these low work function metals are effective for increasing electron injection efficiency and improving device characteristics. However, these low work function metals are generally often unstable in the atmosphere. In order to improve this point, for example, a method of doping an organic layer with a trace amount of lithium, cesium or magnesium and using a highly stable electrode is known. Inorganic salts such as lithium fluoride, cesium fluoride, lithium oxide and cesium oxide can also be used as other dopants. However, it is not limited to these.

In addition, metals such as platinum, gold, silver, copper, iron, tin, aluminum and indium for electrode protection, or alloys using these metals, and inorganic substances such as silica, titania and silicon nitride, polyvinyl alcohol, vinyl chloride. , Laminating a hydrocarbon-based polymer compound or the like is a preferable example. The method for producing these electrodes is also not particularly limited as long as conduction can be achieved, such as resistance heating vapor deposition, electron beam beam deposition, sputtering, ion plating and coating.

<Binder that may be used in each layer>
The materials used for the above-mentioned hole injection layer, hole transport layer, light emitting layer, electron transport layer and electron injection layer can form each layer independently, but as a polymer binder, polyvinyl chloride, polycarbonate, etc. Polystyrene, poly (N-vinylcarbazole), polymethylmethacrylate, polybutylmethacrylate, polyester, polysulfone, polyphenylene oxide, polybutadiene, hydrocarbon resin, ketone resin, phenoxy resin, polyamide, ethyl cellulose, vinyl acetate resin, ABS resin, polyurethane resin It is also possible to disperse and use it in solvent-soluble resins such as phenol resin, xylene resin, petroleum resin, urea resin, melamine resin, unsaturated polyester resin, alkyd resin, epoxy resin, and curable resin such as silicone resin. is there.

<Method of manufacturing organic electroluminescent device>
For each layer constituting the organic electroluminescent device, the material to be composed of each layer is subjected to a thin-film deposition method, resistance heating vapor deposition, electron beam vapor deposition, sputtering, molecular lamination method, printing method, spin coating method or casting method, coating method, or the like. It can be formed by forming a thin film. The film thickness of each layer formed in this manner is not particularly limited and can be appropriately set according to the properties of the material, but is usually in the range of 2 nm to 5000 nm. The film thickness can usually be measured with a crystal oscillation type film thickness measuring device or the like. When a thin film is formed by using a thin film deposition method, the vapor deposition conditions differ depending on the type of material, the target crystal structure and association structure of the film, and the like. The vapor deposition conditions are generally: boat heating temperature +50 to + 400 ° C., vacuum degree ^10-6 to ^10-3 Pa, vapor deposition rate 0.01 to 50 nm / sec, substrate temperature -150 to + 300 ° C., film thickness 2 nm to 5 μm. It is preferable to set appropriately within the range.

Next, as an example of a method for producing an organic electroluminescent device, an organic electroluminescence layer composed of an anode / hole injection layer / hole transport layer / host material and a dopant material / electron transport layer / electron injection layer / cathode A method of manufacturing a light emitting element will be described. A thin film of an anode material is formed on an appropriate substrate by a vapor deposition method or the like to prepare an anode, and then a thin film of a hole injection layer and a hole transport layer is formed on the anode. A host material and a dopant material are co-deposited on this to form a thin film to form a light emitting layer, an electron transport layer and an electron injection layer are formed on the light emitting layer, and a thin film made of a cathode material is formed by a vapor deposition method or the like. By forming it into a cathode, the desired organic electroluminescent device can be obtained. In the above-mentioned production of the organic electroluminescent device, the production order may be reversed, and the cathode, the electron injection layer, the electron transport layer, the light emitting layer, the hole transport layer, the hole injection layer, and the anode may be manufactured in this order. It is possible.

When a DC voltage is applied to the organic electroluminescent element thus obtained, the anode may be applied with + and the cathode as negative polarities, and when a voltage of about 2 to 40 V is applied, it becomes transparent or translucent. Emission can be observed from the electrode side (anode or cathode, or both). The organic electroluminescent device also emits light when a pulse current or an alternating current is applied. The waveform of the applied alternating current may be arbitrary.

<Application example of organic electroluminescent device>
The present invention can also be applied to a display device provided with an organic electroluminescent element, a lighting device provided with an organic electroluminescent element, and the like. A display device or a lighting device provided with an organic electroluminescent element can be manufactured by a known method such as connecting an organic electroluminescent element according to the present embodiment to a known driving device, and can be manufactured by a known method such as direct current driving, pulse driving, or alternating current. It can be driven by appropriately using a known driving method such as driving.

Examples of the display device include a panel display such as a color flat panel display and a flexible display such as a flexible color organic electroluminescent (EL) display (for example, JP-A-10-335066, JP-A-2003-321546). See JP-A-2004-281086, etc.). Further, as the display method of the display, for example, a matrix and / or a segment method can be mentioned. The matrix display and the segment display may coexist in the same panel.

In the matrix, pixels for display are arranged two-dimensionally in a grid pattern or a mosaic pattern, and characters and images are displayed as a set of pixels. The shape and size of the pixels are determined by the application. For example, for displaying images and characters on a personal computer, monitor, or television, quadrangular pixels with a side of 300 μm or less are usually used, and in the case of a large display such as a display panel, pixels with a side on the order of mm should be used. become. In the case of monochrome display, pixels of the same color may be arranged, but in the case of color display, red, green, and blue pixels are displayed side by side. In this case, there are typically a delta type and a stripe type. Then, as the driving method of this matrix, either a line sequential driving method or an active matrix may be used. Line sequential drive has the advantage of having a simpler structure, but considering the operating characteristics, the active matrix may be superior, so it is also necessary to use it properly depending on the application.

In the segment method (type), a pattern is formed so as to display predetermined information, and a predetermined area is made to emit light. For example, time and temperature displays on digital clocks and thermometers, operating status displays of audio equipment and electromagnetic cookers, and panel displays of automobiles can be mentioned.

Examples of the lighting device include a lighting device such as an indoor lighting device, a backlight of a liquid crystal display device, and the like (for example, JP-A-2003-257621, JP-A-2003-277741, JP-A-2004-119211). Etc.). The backlight is mainly used for the purpose of improving the visibility of a display device that does not emit light by itself, and is used for a liquid crystal display device, a clock, an audio device, an automobile panel, a display board, a sign, and the like. In particular, as a backlight for a liquid crystal display device, especially for a personal computer for which thinning is an issue, considering that it is difficult to thin the backlight because the conventional method consists of a fluorescent lamp and a light guide plate, the present embodiment The backlight using the light emitting element according to the above is characterized by being thin and lightweight.

3-2. Other Organic Devices The dimer compound according to the present invention can be used for producing an organic field effect transistor, an organic thin-film solar cell, or the like, in addition to the above-mentioned organic electroluminescent device.

The organic field effect transistor is a transistor that controls a current by an electric field generated by a voltage input, and is provided with a gate electrode in addition to a source electrode and a drain electrode. When a voltage is applied to the gate electrode, an electric field is generated, and the flow of electrons (or holes) flowing between the source electrode and the drain electrode can be arbitrarily dammed to control the current. The field effect transistor is easier to miniaturize than a simple transistor (bipolar transistor), and is often used as an element constituting an integrated circuit or the like.

The structure of the organic field effect transistor is usually provided with a source electrode and a drain electrode in contact with the organic semiconductor active layer formed by using the dimer compound according to the present invention, and further in contact with the organic semiconductor active layer. A gate electrode may be provided with an insulating layer (dielectric layer) interposed therebetween. Examples of the element structure include the following structures.
(1) Substrate / Gate electrode / Insulator layer / Source electrode / Drain electrode / Organic semiconductor active layer (2) Substrate / Gate electrode / Insulator layer / Organic semiconductor active layer / Source electrode / Drain electrode (3) Substrate / Organic Semiconductor active layer / source electrode / drain electrode / insulator layer / gate electrode (4) Substrate / source electrode / drain electrode / organic semiconductor active layer / insulator layer / gate electrode The organic electric field effect transistor configured in this way is It can be applied as a pixel-driven switching element of an active matrix-driven liquid crystal display or an organic electroluminescence display.

The organic thin-film solar cell has a structure in which an anode such as ITO, a hole transport layer, a photoelectric conversion layer, an electron transport layer, and a cathode are laminated on a transparent substrate such as glass. The photoelectric conversion layer has a p-type semiconductor layer on the anode side and an n-type semiconductor layer on the cathode side. The dimer compound according to the present invention can be used as a material for a hole transport layer, a p-type semiconductor layer, an n-type semiconductor layer, and an electron transport layer, depending on its physical properties. The dimer compound according to the present invention can function as a hole transport material or an electron transport material in an organic thin film solar cell. In addition to the above, the organic thin-film solar cell may appropriately include a hole block layer, an electron block layer, an electron injection layer, a hole injection layer, a smoothing layer, and the like. For the organic thin-film solar cell, known materials used for the organic thin-film solar cell can be appropriately selected and used in combination.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto. First, an example of synthesizing a polycyclic aromatic dimer compound will be described below.

Synthesis example (1)
Compound (1-201): 1,3-bis (5,9-diphenyl-5,9-dihydro-5,9-diaza-13b boranaft [3,2,1-de] anthracene-7-yl) thio) Synthesis of benzene

[First stage]
Under a nitrogen atmosphere, 1,3-diiodobenzene (4.48 g, 14 mmol), 3,5-dibromobenzenethiol (5.50 g, 31 mmol) and potassium carbonate (4.27 g, 31 mmol) were added to N, N-dimethylformamide. (DMF) is dissolved in 150 mL, copper iodide (0.286 g, 1.5 mmol) is added thereto, and the mixture is stirred at 100 ° C. for 4 hours, the reaction solution is cooled, the solvent is distilled off under reduced pressure, and the crude product is prepared. Obtained. The crude product obtained using silica gel is filtered (eluent: hexane), and then the residue is washed with hexane using an ultrasonic pulverizer to obtain the desired product 1,3-bis ((3, 3). 5-Dichlorophenyl) thio) benzene (4.73 g, 81% yield) was obtained as a white solid.

The structure of the compound obtained by the NMR spectrum was confirmed.
^{1 1} H-NMR (400 MHz, CDCl ₃ ): δ = 7.11 (d, 4H), 7.21 (t, 2H), 7.34-7.37 (m, 3H), 7.39 (s, 2H).

[Second stage]
Under a nitrogen atmosphere, 1,3-bis ((3,5-dichlorophenyl) thio) benzene (3.56 g, 8.1 mmol), diphenylamine (7.66 g, 45 mmol), Pd ₂ (dba) ₃ (0.456 mg, 0.50 mmol), tritertbutylphosphine (0.215 g, 1.1 mmol) and NaOtBu (6.77 g, 70 mmol) were dissolved in toluene (300 ml) and heated and stirred at 110 ° C. for 18 hours. The reaction mixture was cooled to room temperature, filtered through silica gel (eluent: toluene), and the solvent was evaporated under reduced pressure to give a crude product. The crude product obtained using an ultrasonic crusher was washed with methanol, and the target product, 5,5- (1,3-phenylene bis (sulfandyl)) bis (N ¹ , N ¹ , N ^3). , N ³ -tetraphenylbenzene-1,3-diamine) (7.46 g, yield 86%) was obtained as a white solid.

The structure of the compound obtained by the NMR spectrum was confirmed.
^{1 1} H-NMR (400 MHz, CDCl ₃ ): δ = 6.56 (d, 4H), 6.68 (t, 2H), 6.94 (t, 8H), 7.01-7.02 (m, 18H), 7.10 (s, 1H), 7.15-7.19 (m, 17H).

[Third stage]
5,5- (1,3-phenylene bis (sulfandyl)) bis (N ¹ , N ¹ , N ³ , N ³ -tetraphenylbenzene-1,3-diamine) (0.29 g, 0.30 mmol) Boron tribromide (0.471 g, 1.2 mmol) was added to a flask containing orthodichlorobenzene (10 ml) at room temperature under a nitrogen atmosphere. After completion of the dropping, the temperature was raised to 150 ° C., and the mixture was stirred for 4 hours. Then, the mixture was cooled to room temperature again, N-diisopropylethylamine (0.63 ml, 3.6 mmol) was added, and the mixture was stirred until the exotherm subsided. Then, the reaction solution was distilled off under reduced pressure to obtain a crude product. The crude product obtained using Floridil is filtered (eluent: toluene), the solvent of the filtrate is distilled off, and the mixture is washed with acetonitrile using an ultrasonic pulverizer, and the target product, 1,3-bis. (5,9-diphenyl-5,9-dihydro-5,9-diaza-13b boranaft [3,2,1-de] anthracene-7-yl) thio) benzene (30.3 mg, yield 10%) Obtained as a yellow solid.

The structure of the compound obtained by the NMR spectrum was confirmed.
^{1 1} H-NMR (400 MHz, CDCl ₃ ): δ = 5.76 (s, 4H), 6.70 (d, 4H), 7.06 (t, 1H), 7.06-7.08 (m, 3H), 7.20-7.27 (m, 14H), 7.38-7.47 (m, 8H), 7.54 (t, 8H), 8.91 (d, 4H).

¹³ C-NMR (101MHz, CDCl ₃ ): 104.3 (4C), 117.1 (4C), 120.1 (4C), 128.6 (4C), 129.6 (1C), 130.2 ( 8C), 130.9 (4C), 131.0 (8C), 132.9 (2C), 133.6 (2C), 134.9 (4C), 138.0 (1C), 141.7 (4C) ), 142.3 (2C), 147.1 (2C), 147.4 (4C).

Synthesis example (2)
Compound (1-5400): 1,3-bis (5,9-diphenyl-5,9-dihydro-5,9-diaza-13b boranaft [3,2,1-de] anthracene-7-yl) oxy) Synthesis of benzene

[First stage]
Under a nitrogen atmosphere, resorcinol (11.6 g, 105 mmol), 1-bromo-3,5-dichlorobenzene (55.0 g, 221 mmol), potassium carbonate (4.27 g, 31 mmol) were added to N-methyl-2-pyrrolidone (NMP). ) Dissolve in 180 mL, into which copper iodide (4.01 g, 21.1 mmol), tris (2,4-pentanedionato) iron (III) (7.44 g, 21.1 mmol), triphenylphosphine (22). .1 g, 84.3 mmol) was added, and the mixture was stirred at 180 ° C. for 4 hours, the reaction solution was cooled, and the mixture was filtered through Celite. The filtrate was washed 3 times with water and dried over anhydrous sodium sulfate. The obtained solution is concentrated to obtain a composition organism, and the obtained composition organism is purified by silica gel chromatography (toluene) and then concentrated to obtain 1,3-bis (3,5-dichlorophenoxy). Benzene (15.5 g, yield 37%) was obtained as a colorless liquid.

The structure of the compound obtained by the NMR spectrum was confirmed.
^{1 1} H-NMR (400 MHz, CDCl ₃ ): δ = 6.71 (t, 1H), 6.83 (dd, 2H), 6.91 (d, 4H), 7.11 (t, 2H), 7 .37 (t, 1H).

[Second stage]
Under a nitrogen atmosphere, 1,3-bis (3,5-dichlorophenoxy) benzene (14.5 g, 36.2 mmol), diphenylamine (29.4 g, 174 mmol), Pd ₂ (dba) ₃ (1.66 mg, 1. 81 mmol), tri-tert-butylphosphine tetrafluoroborate (1.05 g, 3.62 mmol) and NaOtBu (20.9 g, 217 mmol) were dissolved in 300 mL of toluene and heated and stirred at 110 ° C. for 8 hours. The reaction mixture was cooled to room temperature, filtered through silica gel (eluent: toluene), and the solvent was evaporated under reduced pressure to give a crude product. The obtained crude product was recrystallized from a mixed solvent (toluene / heptane = 2/1 (volume ratio)), and 5,5- (1,3-phenylene bis (oxy)) bis (N ¹ , N ¹ , N ³ , N ³ -tetraphenylbenzene-1,3-diamine) (18.8 g, yield 56%) was obtained as a white solid.

The structure of the compound obtained by the NMR spectrum was confirmed.
^{1 1} H-NMR (400 MHz, CDCl ₃ ): δ = 6.30 (d, 4H), 6.51-55 (m, 3H), 6.58 (t, 2H), 6.95 (t, 8H) , 7.07 (d, 16H), 7.19 (t, 16H), 7.27 (t, 1H).

[Third stage]
5,5- (1,3-phenylene bis (oxy)) bis (N ¹ , N ¹ , N ³ , N ³ -tetraphenylbenzene-1,3-diamine) (1 g, 1.07 mmol) and ortodichlorobenzene A solution of boron tribromide dichlorobenzene (2.15 mL, 2.0 mol / L) was added to a flask containing (30 ml) at room temperature under a nitrogen atmosphere. After completion of the dropping, the temperature was raised to 150 ° C., and the mixture was stirred for 4 hours. Then, the mixture was cooled to 0 ° C., an aqueous sodium hydrogen carbonate solution was added, and the mixture was stirred until the heat generation subsided. Then, the reaction solution was distilled off under reduced pressure to obtain a crude product. The obtained crude product is filtered with Floridil (eluent: toluene), the solvent of the filtrate is distilled off, and the mixture is washed with acetonitrile using an ultrasonic pulverizer to make the compound (1-5400) a yellow solid. Obtained as.

By appropriately changing the raw material compound, the other dimer compound of the present invention can be synthesized by a method similar to the above-mentioned synthesis example. Next, an evaluation of the basic physical properties of the dimer compound and an example of manufacturing an organic EL device will be described.

(1) Evaluation method of basic physical properties
<Preparation of sample>
As a method for evaluating the absorption property and the light emission property (fluorescence and phosphorescence) of the compound, there are a case where the compound is dissolved in a solvent and evaluated in the solvent, and a case where the compound is evaluated in a thin film state. Further, in the case of evaluation in a thin film state, depending on the usage mode of the compound to be evaluated in the organic EL element, only the compound to be evaluated is thinned and evaluated, and the compound to be evaluated is dispersed in an appropriate matrix material. It may be thinned and evaluated.

As the matrix material, commercially available PMMA (polymethylmethacrylate) or the like can be used. A thin film sample dispersed in PMMA is prepared, for example, by dissolving PMMA and a compound to be evaluated in toluene, and then forming a thin film on a transparent support substrate (10 mm × 10 mm) made of quartz by a spin coating method. Can be done.

Further, a method for producing a thin film sample when the matrix material is a host material will be described below. A transparent quartz support substrate (10 mm x 10 mm x 1.0 mm) is fixed to a substrate holder of a commercially available vapor deposition equipment (manufactured by Showa Vacuum Co., Ltd.), and a molybdenum vapor deposition boat containing a host material and a dopant material are inserted. Install a molybdenum vapor deposition boat. Next, the vacuum chamber is depressurized to 5 × 10 ^-4 Pa, and the vapor deposition boat containing the host material and the vapor deposition boat containing the dopant material are heated at the same time to vapor deposit to an appropriate film thickness and host. A mixed thin film of material and dopant material is formed. The deposition rate is controlled according to the set weight ratio of the host material and the dopant material.

<Evaluation of absorption characteristics and light emission characteristics>
The absorption spectrum was measured using an ultraviolet-visible near-infrared spectrophotometer (Shimadzu Corporation, UV-2600). The fluorescence spectrum or phosphorescence spectrum was measured using a spectrofluorescence meter (F-7000, manufactured by Hitachi High-Tech Co., Ltd.).

For the measurement of the fluorescence spectrum, photoluminescence was measured by exciting at an appropriate excitation wavelength at room temperature. For the measurement of the phosphorescence spectrum, the sample was measured in a state of being immersed in liquid nitrogen (temperature 77K) using the attached cooling unit. In order to observe the phosphorescence spectrum, an optical chopper was used to adjust the delay time from the excitation light irradiation to the start of measurement. The sample was excited at an appropriate excitation wavelength and photoluminescence was measured.

Further, the fluorescence quantum yield is measured using an absolute PL quantum yield measuring device (C9920-02G, manufactured by Hamamatsu Photonics Co., Ltd.).

<Evaluation of fluorescence lifetime (delayed fluorescence)>
The fluorescence lifetime is measured at 300 K using a fluorescence lifetime measuring device (C11367-01, manufactured by Hamamatsu Photonics Co., Ltd.). Observe components with fast and slow fluorescence lifetimes at the maximum emission wavelength measured at the appropriate excitation wavelength. In the measurement of the fluorescence lifetime of a general organic EL material that emits fluorescence at room temperature, a slow component involving a triplet component derived from phosphorescence is rarely observed due to the deactivation of the triplet component due to heat. .. When a slow component is observed in the compound to be evaluated, it means that the triplet energy having a long excitation lifetime is transferred to the singlet energy by thermal activation and observed as delayed fluorescence.

<Calculation of energy gap (Eg)>
It is calculated from the long wavelength end A (nm) of the absorption spectrum at Eg = 1240 / A.

_<E S, the calculation of the _{E T} and ΔEST>
Singlet excitation energy _{(E S)} is calculated by Es = 1240 / B from the maximum emission wavelength B of the fluorescence spectrum (nm). Further, the triplet excitation energy _{(E T)} is calculated from the phosphorescence spectrum maximum emission wavelength C (nm) at _E T = 1240 / C.

DerutaEST is defined as the energy difference _{E S} and _{E T ΔEST = E S -E T} . ΔEST is, for example, "Purely organic electroluminescent material realizing 100% conversion from electricity to light", H. Kaji, H. Suzuki, T. Fukushima, K. Shizu, K. Katsuaki, S. Kubo, T. Komino, It can also be calculated by the method described in H. Oiwa, F. Suzuki, A. Wakamiya, Y. Murata, C. Adachi, Nat. Commun. 2015, 6, 8476.

(2) Evaluation of Basic Physical Properties of Compound (1-201) The absorption spectrum was measured by preparing a thin film-forming substrate (made of quartz) in which compound (1-201) was dispersed in PMMA at a concentration of 1% by weight. It was.
For the measurement of the fluorescence spectrum, a thin film-forming substrate (made of quartz) in which the compound (1-201) was dispersed in PMMA at a concentration of 1% by weight was prepared and excited at an excitation wavelength of 340 nm to measure photoluminescence. As a result, the maximum emission wavelength was 451 nm, _{E S} was calculated to 2.75 eV. Further, when the same substrate was prepared and excited at an excitation wavelength of 400 nm and the fluorescence quantum yield was measured, it was as high as 79%.
For the measurement of the phosphorescence spectrum, a thin film-forming substrate (made of quartz) in which the compound (1-201) was dispersed in PMMA at a concentration of 1% by weight was prepared and excited at an excitation wavelength of 340 nm to measure photoluminescence. As a result, the maximum emission wavelength was 492 nm, _{E T} was calculated to 2.52 eV.
Each of the above spectra is shown in FIG.

As described above, the compound (1-201) is deep blue fluorescence spectra, high fluorescence quantum yield and a suitable energy (Es, E _T) because it has can be expected particularly applicable to the light-emitting layer ..

(3) Evaluation method of organic EL element The evaluation items of the organic EL element include drive voltage (V), emission wavelength (nm), CIE chromaticity (x, y), external quantum efficiency (%), and maximum emission spectrum. There are wavelength (nm) and half width (nm). For these evaluation items, values at an appropriate emission brightness can be used.

The quantum efficiency of the organic EL element includes the internal quantum efficiency and the external quantum efficiency. The internal quantum efficiency is the ratio at which the external energy injected as electrons (or holes) into the light emitting layer is converted into pure photons. Is shown. On the other hand, the external quantum efficiency is calculated based on the amount of these photons emitted to the outside of the element, and some of the photons generated in the light emitting layer are absorbed or continuously reflected inside the element. Therefore, the external quantum efficiency is lower than the internal quantum efficiency because it is not emitted to the outside of the element.

The method for measuring the spectral radiance (emission spectrum) and the external quantum efficiency is as follows. A voltage / current generator R6144 manufactured by Advantest Co., Ltd. is used to make the element emit light by applying a voltage. A spectral radiance meter SR-3AR manufactured by TOPCON is used to measure the spectral radiance in the visible light region from the direction perpendicular to the light emitting surface. Assuming that the light emitting surface is a perfect diffusion surface, the value obtained by dividing the measured spectral radiance value of each wavelength component by the wavelength energy and multiplying by π is the number of photons at each wavelength. Next, the number of photons is integrated in the entire observed wavelength region to obtain the total number of photons emitted from the device. The value obtained by dividing the applied current value by the elementary charge is the number of carriers injected into the device, and the value obtained by dividing the total number of photons emitted from the device by the number of carriers injected into the device is the external quantum efficiency. The full width at half maximum of the emission spectrum is obtained as the width between the upper and lower wavelengths at which the intensity becomes 50% centering on the maximum emission wavelength.

Examples of the layer structure of the organic EL element include the layer structure shown in Table 1. The application of the dimer compound of the present invention is not limited to the following layer structure, and the film thickness and constituent material of each layer can be appropriately changed depending on the basic physical properties of the dimer compound of the present invention.

In Table 1, "HI-1" (hole injection layer material) is N ⁴ , N ^4' -diphenyl-N ⁴ , N ^4' -bis (9-phenyl-9H-carbazole-3-yl)-[1. , 1'-biphenyl] -4,4'-diamine, and "HAT-CN" (hole injection layer material) is 1,4,5,8,9,12-hexaazatriphenylene hexacarbonitrile. "HT-1" (hole transport layer material) is N- ([1,1'-biphenyl] -4-yl) -9,9-dimethyl-N- (4- (9-phenyl-9H-carbazole-) 3-Il) Phenyl) -9H-Fluoren-2-amine, "HT-2" (hole transport layer material) is N, N-bis (4- (dibenzo [b, d] furan-4-yl) ) Phenyl)-[1,1': 4', 1 "-terphenyl] -4-amine, and "EMH1" (light emitting layer host material) is 9-phenyl-10- (4-phenylnaphthalene-1-). Il) anthracene, "ET-1" (electron transport layer material) is 4,6,8,10-tetraphenyl [1,4] benzoxabolinino [2,3,4-kl] phenoxabolinine. "ET-2" (electron transport layer material) is 3,3'-((2-phenylanthracene-9,10-diyl) bis (4,1-phenylene)) bis (4-methylpyridine), and " The chemical structure is shown below together with "Liq".

(4) Evaluation of Organic EL Device Using Compound (1-201) as Dopant An organic EL device having the layer structure shown in Table 1 can be produced by the following procedure. First, a 26 mm × 28 mm × 0.7 mm glass substrate (manufactured by Atsugi Micro Co., Ltd.) having an ITO film formed to a thickness of 150 nm by sputtering is used as a transparent support substrate. This transparent support substrate is fixed to a substrate holder of a commercially available thin film deposition apparatus (manufactured by Choshu Sangyo Co., Ltd.), and HI-1 (hole injection layer material), HAT-CN (hole injection layer material), HT-1 ( Hole transport layer material), HT-2 (hole transport layer material), EMH1 (host material), compound (1-201) (dopant material), ET-1 (electron transport layer material), ET-2 (electron) (Transport layer material), a molybdenum vapor deposition boat containing Liq, a SiC jar containing magnesium, and a SiC jar containing silver are installed.

The following layers are sequentially formed on the ITO film of the transparent support substrate. The vacuum chamber is depressurized to 1 × 10 ^-4 Pa, and HI-1 is first heated to be vapor-deposited to a film thickness of 40 nm, and then HAT-CN is heated to be vapor-deposited to a film thickness of 5 nm. A hole injection layer composed of two layers is formed. Next, HT-1 is heated to be vapor-deposited to a film thickness of 15 nm, and HT-2 is further heated to be vapor-deposited to a film thickness of 10 nm to form a hole transport layer composed of two layers. Next, EMH1 and compound (1-201) are simultaneously heated and vapor-deposited to a film thickness of 25 nm to form a light emitting layer. The deposition rate is adjusted so that the weight ratio of EMH1 to compound (1-201) is approximately 98: 2. Next, ET-1 is heated and vapor-deposited to a film thickness of 5 nm, and ET-2 and Liq are simultaneously heated and vapor-deposited to a film thickness of 25 nm to form an electron transport layer composed of two layers. To do. The deposition rate is adjusted so that the weight ratio of ET-2 and Liq is approximately 50:50. The vapor deposition rate of each layer is 0.01 to 1 nm / sec. After that, Liq is heated and vapor-deposited at a vapor deposition rate of 0.01 to 0.1 nm / sec so as to have a film thickness of 1 nm, and then magnesium and silver are simultaneously heated and vapor-deposited to a film thickness of 100 nm. Form a cathode. The vapor deposition rate is adjusted between 0.1 nm and 10 nm / sec so that the atomic number ratio of magnesium and silver is 10: 1. In this way, the organic EL element is obtained.

In order to evaluate the obtained organic EL device, brightness, chromaticity, external quantum efficiency, and the like can be measured by applying a DC voltage with the ITO electrode as an anode and the MgAg electrode as a cathode.

(5) Evaluation of Organic EL Device Using Compound (1-5400) as Dopant By replacing compound (1-201) with compound (1-5400), an organic EL device can be obtained in the same manner as above, and each evaluation Can be done.

The dimer compound of the present invention can be evaluated as an organic EL device by evaluating basic physical properties in the same manner as the compound (1-201) and the compound (1-5400). However, depending on the basic physical properties, it can be used as a material for other layers such as a material for a charge transport layer in addition to the host material.

In the present invention, by providing an excellent polycyclic aromatic dimer compound that can be used as a material for an organic EL device, for example, the choice of a material for a device such as a material for an organic EL device can be increased. .. Further, by using this dimer compound, it is possible to provide an excellent organic EL element, a display device provided with the same, a lighting device provided with the same, and the like.

100 Organic electroluminescent device 101 Substrate 102 Anode 103 Hole injection layer 104 Hole transport layer 105 Light emitting layer 106 Electron transport layer 107 Electron injection layer 108 Cathode

Claims (12)

It is a dimer compound composed of two partial structures represented by the following general formula (1) and a linking group L1 that connects the two partial structures.
(In the above formula (1),
Rings A, B and C are independently aryl rings or heteroaryl rings, and at least one hydrogen in these rings may be substituted.
Y ¹ is B, P, P = O, P = S, Al, Ga, As, Si-R or Ge-R, and R of the Si-R and Ge-R is aryl, alkyl or cycloalkyl. Yes,
X ¹ and X ² are independently>O,>N-R,> S or> Se, and the R of> N-R may be substituted aryl, which may be substituted. Heteroaryl, optionally substituted alkyl or optionally substituted cycloalkyl, wherein the> N-R R is attached to the A, B and / or C rings by a linking group L2. May be good. )
The substructures represented by the formula (1) may be the same structure or different structures, but in the two substructures, Y ¹ is both B, X ¹ and X ² are both>. The case of O is excluded, and the case where Y ¹ is both P = O and X ¹ and X ² are both> O is excluded.
The linking group L1 is a single bond, an arylene having 6 to 30 carbon atoms, a hetero arylene having 2 to 30 carbon atoms, an alkylene having 1 to 24 carbon atoms, an alkenylene having 1 to 24 carbon atoms, and an alkynylene having 1 to 24 carbon atoms. -O-, -S-,> N-R, or a combination thereof, and the R of> N-R is an aryl having 6 to 16 carbon atoms, a heteroaryl having 2 to 20 carbon atoms, and 1 to 1 carbon atoms. It is an alkyl of 12 or a cycloalkyl of 3 to 16 carbon atoms, and at least one hydrogen in the linking group L1 is an aryl having 6 to 16 carbon atoms and a heteroaryl having 2 to 20 carbon atoms and having an alkyl or carbon number of 1 to 12 carbon atoms. It may be substituted with 3 to 16 cycloalkyls.
A dimer compound in which at least one hydrogen in the dimer compound may be substituted with cyano, halogen or deuterium. In the above formula (1),
Rings A, B, and C are independently aryl and heteroaryl rings, and at least one hydrogen in these rings is a substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or Unsubstituted diarylamino, substituted or unsubstituted diheteroarylamino, substituted or unsubstituted aryl heteroarylamino, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted alkoxy or substituted or It may be substituted with an unsubstituted aryloxy, and these rings are 5- or 6-membered rings that share a bond with the fused bicyclic structure in the center of the above formula composed of Y ¹ , X ¹ and X ^2. Has a ring and
Y ¹ is B, P, P = O, P = S, Al, Ga, As, Si-R or Ge-R, and R of the Si-R and Ge-R is aryl, alkyl or cycloalkyl. Yes,
X ¹ and X ² are independently>O,>N-R,> S or> Se, and the R of> N-R may be substituted with alkyl or cycloalkyl, respectively. Alternatively, it may be heteroaryl, alkyl or cycloalkyl substituted with cycloalkyl, and the R of> N-R is selected from -O-, -S-, -C (-R) _2- and single bond. The linking group L2 may be bonded to the A ring, the B ring and / or the C ring, and the R of −C (−R) ₂₋ is hydrogen, alkyl or cycloalkyl, and
The substructures represented by the formula (1) may be the same structure or different structures, but in the two substructures, Y ¹ is both B, X ¹ and X ² are both>. The case of O is excluded, and the case where Y ¹ is both P = O and X ¹ and X ² are both> O is excluded.
The linking group L1 is a single bond, an arylene having 6 to 16 carbon atoms, a hetero arylene having 2 to 20 carbon atoms, an alkylene having 1 to 12 carbon atoms, an alkenylene having 1 to 12 carbon atoms, and an alkynylene having 1 to 12 carbon atoms. -O-, -S-,> N-R, or a combination thereof, and the R of> N-R is an aryl having 6 to 12 carbon atoms, a heteroaryl having 2 to 15 carbon atoms, and 1 to 1 carbon atoms. It is an alkyl of 6 or a cycloalkyl of 3 to 14 carbon atoms, and at least one hydrogen in the linking group L1 is an aryl having 6 to 12 carbon atoms, a heteroaryl having 2 to 15 carbon atoms, an alkyl or carbon having 1 to 6 carbon atoms. It may be substituted with the number 3-14 cycloalkyl.
At least one hydrogen in the dimer compound may be substituted with cyano, halogen or deuterium.
The dimer compound according to claim 1. The dimer compound according to claim 1, wherein the partial structure is represented by the following general formula (2).
In the above formula (2),
R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ and R ¹¹ are independently hydrogen, aryl, heteroaryl, diarylamino, and di. Heteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkoxy or aryloxy, in which at least one hydrogen may be substituted with aryl, heteroaryl, alkyl or cycloalkyl, and R ¹ to Adjacent groups of R ¹¹ may be bonded to each other to form an aryl ring or a heteroaryl ring together with an a ring, a b ring or a c ring, and at least one hydrogen in the formed ring is an aryl or heteroaryl. , Diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkoxy or aryloxy, at least one of which is substituted with aryl, heteroaryl, alkyl or cycloalkyl. May be
Y ¹ is B, P, P = O, P = S, Al, Ga, As, Si-R or Ge-R, and R of the Si-R and Ge-R is an aryl having 6 to 12 carbon atoms. , Alkyl with 1 to 6 carbon atoms or cycloalkyl with 3 to 14 carbon atoms.
X ¹ and X ² are independently>O,>N-R,> S or> Se, and the R of> N-R is an aryl having 6 to 12 carbon atoms and 2 to 15 carbon atoms. Heteroaryl, alkyl with 1 to 6 carbons or cycloalkyl with 3 to 14 carbons, with> N-R R from -O-, -S-, -C (-R) _2- and single bond. The a ring, b ring and / or c ring may be bonded to the a ring, the b ring and / or the c ring by the connecting group L2 selected, and the R of −C (−R) ₂₋ is an alkyl having 1 to 6 carbon atoms or 3 to 3 carbon atoms. 14 cycloalkyl, and
The substructures represented by the formula (2) may be the same structure or different structures, but in the two substructures, Y ¹ is both B, X ¹ and X ² are both>. The case of O is excluded, and the case where Y ¹ is both P = O and X ¹ and X ² are both> O is excluded.
The linking group L1 includes a single bond, an arylene having 6 to 12 carbon atoms, a heteroarylene having 2 to 15 carbon atoms, an alkylene having 1 to 6 carbon atoms, an alkenylene having 1 to 6 carbon atoms, and an alkynylene having 1 to 6 carbon atoms. -O-, -S-,> N-R, or a combination thereof, and the R of> N-R is an aryl having 6 to 12 carbon atoms, a heteroaryl having 2 to 15 carbon atoms, and 1 to 1 carbon atoms. It is an alkyl of 6 or a cycloalkyl of 3 to 14 carbon atoms.
At least one hydrogen in the dimer compound may be substituted with cyano, halogen or deuterium. In the above formula (2),
R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ and R ¹¹ are independently hydrogen, aryl and carbon with 6 to 30 carbon atoms, respectively. number 2-30 heteroaryl, diarylamino (where aryl is aryl of 6 to 12 carbon atoms), cycloalkyl alkyl or 3-20 carbon atoms having 1 to 20 carbon atoms, ^also, of R 1 ^{to R 11} Adjacent groups thereof may be bonded to each other to form an aryl ring having 9 to 16 carbon atoms or a heteroaryl ring having 6 to 15 carbon atoms together with the a ring, b ring or c ring, and in the formed ring. At least one hydrogen may be substituted with an aryl having 6 to 10 carbon atoms, an alkyl having 1 to 6 carbon atoms, or a cycloalkyl having 3 to 14 carbon atoms.
Y ¹ is B, P, P = O, P = S or Si-R, and R of the Si-R is an aryl having 6 to 10 carbon atoms, an alkyl having 1 to 4 carbon atoms, or 5 to 10 carbon atoms. Cycloalkyl,
X ¹ and X ² are independently>O,> N-R or> S, and the R of> N-R is an aryl having 6 to 10 carbon atoms and an alkyl or carbon having 1 to 4 carbon atoms. It is a cycloalkyl of number 5-10, and
Two of the substructures represented by the formula (2) are the same structure, except when Y ¹ is both B and X ¹ and X ² are both> O in the ^two substructures, and Y Excludes cases where ¹ is both P = O and X ¹ and X ² are both> O.
The linking group L1 is a single bond, an arylene having 6 to 12 carbon atoms, an alkylene having 1 to 6 carbon atoms, an alkenylene having 1 to 6 carbon atoms, -O-, -S-,> N-R, or any of these. It is a combination, and R of> N-R is an aryl having 6 to 10 carbon atoms.
At least one hydrogen in the dimer compound may be substituted with cyano, halogen or deuterium.
The dimer compound according to claim 3. The dimer compound according to claim 1, which is represented by any of the following chemical structural formulas.
A material for an organic device containing the dimer compound according to any one of claims 1 to 5. The material for an organic device according to claim 6, wherein the material for an organic device is a material for an organic electroluminescent device, a material for an organic field effect transistor, or a material for an organic thin film solar cell. The material for an organic electroluminescent device according to claim 7, which is a material for a light emitting layer. An organic electroluminescent device having a pair of electrodes composed of an anode and a cathode, and a light emitting layer arranged between the pair of electrodes and containing the light emitting layer material according to claim 8. It has an electron transport layer and / or an electron injection layer arranged between the cathode and the light emitting layer, and at least one of the electron transport layer and the electron injection layer is a quinolinol-based metal complex, a pyridine derivative, or a phenanthroline derivative. The organic electroluminescent device according to claim 9, which comprises at least one selected from the group consisting of a borane derivative and a benzimidazole derivative. The electron transporting layer and / or electron injecting layer further comprises an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal oxide, an alkali metal halide, an alkaline earth metal oxide, and an alkaline earth metal. Claim that it contains at least one selected from the group consisting of halides, oxides of rare earth metals, halides of rare earth metals, organic complexes of alkali metals, organic complexes of alkaline earth metals and organic complexes of rare earth metals. 10. The organic electric field light emitting element according to 10. A display device or a lighting device including the organic electroluminescent element according to any one of claims 9 to 11.