Patent Application
20240389459
The present invention relates to specific compounds, a material, preferably an emitter material, for an organic electroluminescence device comprising said specific compounds, an organic electroluminescence device comprising said specific compounds, an electronic equipment comprising said organic electroluminescence device, a light emitting layer comprising at least one host and at least one dopant, wherein the dopant comprises at least one of said specific compounds, and the use of said compounds in an organic electroluminescence device.
When a voltage is applied to an organic electroluminescence device (hereinafter may be referred to as an organic EL device), holes are injected to an emitting layer from an anode and electrons are injected to an emitting layer from a cathode. In the emitting layer, injected holes and electrons are re-combined and excitons are formed.
An organic EL device comprises an emitting layer between the anode and the cathode. Further, there may be a case where it has a stacked layer structure comprising an organic layer such as a hole-injecting layer, a hole-transporting layer, an electron-injecting layer, an electron-transporting layer, etc.
WO2019132040 A1 relates to a compound of the following formula (I) and an organic electroluminescent device using the same.
provided that at least one of R1 to Ra is a group represented by the following formula (2)
-L1-HAr (2)
In formula (2), L1 represents a single bond, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic ring having 5 to 30 ring atoms and HAr is a substituted or unsubstituted monovalent heterocyclic group having 5 to 50 ring atoms.
WO2021020931 A1 relates to a compound represented by formula (I) and an organic light emitting device comprising same.
wherein one or more from among the substitution groups of A and B, and R1-R3 are groups expressed by formula (2)
WO2019132028 A1 relates to a compound represented by formula (I) and an organic electroluminescent device using the same.
JP2021014446 A relates to a multimer of a polycyclic aromatic compound represented by the following general formula (I) or a polycyclic aromatic compound having a plurality of structures represented by the following general formula (I).
wherein at least one hydrogen in at least one ring of the C ring is substituted with a group represented by the above formula (Am),
in which Ar1 and Ar2 are independently aryl or hetero, respectively.
KR102225908 B1 relates to a heterocyclic compound of the following formula (I) and an organic light emitting device including the same.
wherein at least one of two adjacent substituent groups of a substituted or unsubstituted ring formed by bonding of adjacent substituents among R11 to R14, R21 to R24, R31 to R35, R41 to R43, and R51 to R55 is represented by Formula (2)
The specific structure and substitution pattern of polycyclic compounds has a significant impact on the performance of the polycyclic compounds in organic electronic devices.
Notwithstanding the developments described above, there remains a need for organic electroluminescence devices comprising new materials, especially dopant (=emitter) materials, to provide improved performance of electroluminescence devices.
Accordingly, it is an object of the present invention, with respect to the aforementioned related art, to provide materials suitable for providing organic electroluminescence devices which ensure good performance of the organic electroluminescence devices, especially good EQEs and/or a long lifetime. More particularly, it should be possible to provide dopant (=emitter) materials, especially blue light emitting dopant materials having a narrow spectrum (smaller FWHM), i.e. good color purity when used as dopant in organic electroluminescence devices.
Said object is according to one aspect of the present invention solved by a compound represented by formula (I):
The compounds of formula (I) can be in principal used in any layer of an EL device. Preferably, the compound of formula (I) is a dopant (=emitter) in organic EL elements, especially in the light-emitting layer, more preferably a fluorescent dopant. Particularly, the compounds of formula (I) are used as fluorescent dopants in organic EL devices, especially in the light-emitting layer.
The term organic EL device (organic electroluminescence device) is used interchangeably with the term organic light-emitting diode (OLED) in the present application.
It has been found that the specific compounds of formula (I) show a narrow emission characteristic, preferably a narrow fluorescence, more preferably a narrow blue fluorescence. Such a narrow emission characteristic is suitable to prevent energy losses by outcoupling. The compounds of formula (I) according to the present invention preferably have a Full width at half maximum (FWHM) of lower than 30 nm, more preferably lower than 25 nm.
It has further been found that organic EL devices comprising the compounds of the present invention are generally characterized by high external quantum efficiencies (EQE) and long lifetimes, especially when the specific compounds of formula (I) are used as dopants (light emitting material), especially fluorescent dopants in organic electroluminescence devices.
Examples of the optional substituent(s) indicated by “substituted or unsubstituted” and “may be substituted” referred to above or hereinafter include an aryl group having from 6 to 60, preferably from 6 to 30, more preferably from 6 to 18 ring carbon atoms which is in turn unsubstituted or substituted, a heteroaryl group having from 5 to 60, preferably 5 to 30, more preferably 5 to 18 ring atoms which is in turn unsubstituted or substituted, an alkyl group having 1 to 20, preferably 1 to 8 carbon atoms, a cycloalkyl group having 3 to 20, preferably 3 to 6 carbon atoms, a group OR20, an alkylhalide group having 1 to 20, preferably 1 to 8 carbon atoms, a halogen atom (fluorine, chlorine, bromine, iodine), CN, C(═O)R22, COOR23, a carboxamidalkyl group having 1 to 20 carbon atoms, preferably 1 to 8 carbon atoms, a silyl group SiR24R25R26, B(R21)2, a group SR21, NO2 and a carboxamidaryl group having 6 to 18 ring carbon atoms in the aryl residue;
The terms hydrogen, halogen, an alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted, an alkylhalide group having from 1 to 20 carbon atoms which is unsubstituted or substituted, a cycloalkyl group having from 3 to 20 ring carbon atoms which is unsubstituted or substituted, a substituted or unsubstituted aryl group having 6 to 60, preferably from 6 to 30, more preferably from 6 to 18 ring carbon atoms; a substituted or unsubstituted heteroaryl group having 5 to 60, preferably 5 to 30, more preferably 5 to 18 ring atoms, C(═O)R22, a carboxamidalkyl group having 1 to 20 carbon atoms, preferably 1 to 8 carbon atoms, a carboxamidaryl group having 6 to 18 ring carbon atoms in the aryl residue, OR20, SR21, C(═O)R22, COOR23, SiR24R25R26, an aralkyl group having from 7 to 60 carbon atoms which is unsubstituted or substituted, an alkenyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted and an alkynyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted are known in the art and generally have the following meaning, if said groups are not further specified in specific embodiments mentioned below:
In the invention, hydrogen includes isotopes differing in the number of neutrons, i.e. protium, deuterium and tritium.
In this specification, at a bondable position in a chemical formula where a symbol such as “R”, or “D” representing a deuterium atom is not indicated, a hydrogen atom, that is, a protium atom, a deuterium atom or a tritium atom is bonded.
The presence of deuterium atoms in a compound is confirmed by mass spectrometry or 1HNMR spectrometry. The position where a deuterium atom is bonded to the compound is determined by 1H-NMR analysis. Specifically, the following method can be used.
A compound to be measured is subjected to mass spectrometry. If the molecular weight is increased by 1 compared to that of the corresponding compound in which all hydrogen atoms are protium atoms, it can be confirmed that the compound contains one deuterium atom. In addition, the number of deuterium atoms in the molecule can be confirmed by the integral value obtained by 1H-NMR analysis of the compound to be measured, since a deuterium atom gives no signal in 1H-NMR analysis. In addition, the position in the compound where the deuterium atom is bonded can be identified by carrying out 1H-NMR analysis of the compound to be measured, and assigning the obtained signals.
The substituted or unsubstituted aryl group having 6 to 60, preferably from 6 to 30, more preferably from 6 to 18 ring carbon atoms most preferably having from 6 to 13 ring carbon atoms, may be a non-condensed aromatic group or a condensed aromatic group. Specific examples thereof include phenyl group, naphthyl group, phenanthryl group, biphenyl group, terphenyl group, fluoranthenyl group, triphenylenyl group, phenanthrenyl group, fluorenyl group, indenyl group, anthracenyl, chrysenyl, spirofluorenyl group, benzo[c]phenanthrenyl group, with phenyl group, naphthyl group, biphenyl group, terphenyl group, phenanthryl group, triphenylenyl group, fluorenyl group, indenyl group and fluoranthenyl group being preferred, phenyl group, 1-naphthyl group, 2-naphthyl group, biphenyl-2-yl group, biphenyl-3-yl group, biphenyl-4-yl group, phenanthrene-9-yl group, phenanthrene-3-yl group, phenanthrene-2-yl group, triphenylene-2-yl group, fluorene-2-yl group, especially a 9,9-di-C1-20alkylfluorene-2-yl group, like a 9,9-dimethylfluorene2-yl group, a 9,9-di-C6-18arylfluorene-2-yl group, like a 9,9-diphenylfluorene-2-yl group, or a 9,9-di-C5-18heteroarylfluorene-2-yl group, 1,1-dimethylindenyl group, fluoranthene-3-yl group, fluoranthene-2-yl group and fluoranthene-8-yl group being more preferred, and phenyl group being most preferred.
The substituted or unsubstituted heteroaryl group having 5 to 60, preferably 5 to 30, more preferably 5 to 18 ring atoms, most preferably having from 5 to 13 ring atoms, may be a non-condensed heteroaromatic group or a condensed heteroaromatic group. Specific examples thereof include the residues of pyrrole ring, isoindole ring, benzofuran ring, isobenzofuran ring, benzothiophene, dibenzothiophene ring, isoquinoline ring, quinoxaline ring, quinazoline, phenanthridine ring, phenanthroline ring, pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring, indole ring, quinoline.ring, acridine ring, carbazole ring, furan ring, thiophene ring, benzoxazole ring, benzothiazole ring, benzimidazole ring, dibenzofuran ring, triazine ring, oxazole ring, oxadiazole ring, thiazole ring, thiadiazole ring, triazole ring, imidazole ring, indolidine ring, imidazopyridine ring, 4-imidazo[1,2-a]benzimidazoyl, 5-benzimidazo[1,2-a]benzimidazoyl, and benzimidazolo[2,1-b][1,3]benzothiazolyl, with the residues of benzofuran ring, indole ring, benzothiophene ring, dibenzofuran ring, carbazole ring, and dibenzothiophene ring being preferred, and the residues of benzofuran ring, 1-phenylindol ring, benzothiophene ring, dibenzofuran-1-yl group, dibenzofuran-3-yl group, dibenzofuran-2-yl group, dibenzofuran-4-yl group, 9-phenylcarbazole-3-yl group, 9-phenylcarbazole-2-yl group, 9-phenylcarbazole-4-yl group, dibenzothiophene-2-yl group, and dibenzothiophene-4-yl, dibenzothiophene-1-yl group, and dibenzothiophene-3-yl group being more preferred.
Examples of the alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, s-butyl group, isobutyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, neopentyl group, 1-methylpentyl group, with methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, s-butyl group, isobutyl group, t-butyl group being preferred. Preferred are alkyl groups having 1 to 8 carbon atoms, more preferably 1 to 4 carbon atoms. Suitable examples for alkyl groups having 1 to 8 carbon atoms respectively 1 to 4 carbon atoms are mentioned before.
Examples of the alkylhalide group having from 1 to 20 carbon atoms which is unsubstituted or substituted include those disclosed as alkyl groups wherein the hydrogen atoms thereof are partly or entirely substituted by halogen atoms. Preferred alkylhalide groups are fluoroalkyl groups having 1 to 20 carbon atoms including the alkyl groups mentioned above wherein the hydrogen atoms thereof are partly or entirely substituted by fluorine atoms, for example CF3.
Examples of the alkenyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted include ethene group, n-propene group, isopropene group, n-butene group, isobutene group, n-pentene group, n-hexene group, n-heptene group, n-octene group, n-nonene group, n-decene group, n-undecene group, n-dodecene group, n-tridecene group, n-tetradecene group, n-pentadecene group, n-hexadecene group, n-heptadecene group, n-octadecene group, with ethene group, n-propene group, isopropene group, n-butene group, isobutene group being preferred. Preferred are alkenyl groups having 2 to 8 carbon atoms, more preferably 2 to 4 carbon atoms. Suitable examples for alkenyl groups having 2 to 8 carbon atoms respectively 2 to 4 carbon atoms are mentioned before.
Examples of the alkynyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted include ethynyl group, n-propynyl group, n-butynyl group, n-pentynyl group, n-hexynyl group, n-heptynyl group, n-octynyl group, with ethynyl group, n-propynyl group, n-butynyl group being preferred. Preferred are alkynyl groups having 2 to 8 carbon atoms, more preferably 2 to 4 carbon atoms. Suitable examples for alkynyl groups having 2 to 8 carbon atoms respectively 2 to 4 carbon atoms are mentioned before.
Examples of the cycloalkyl group having from 3 to 20 ring carbon atoms which is unsubstituted or substituted include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cyclooctyl group, and adamantyl group, with cyclopentyl group, and cyclohexyl group being preferred. Preferred are cycloalkyl groups having 3 to 6 carbon atoms. Suitable examples for cycloalkyl groups having 3 to 6 carbon atoms are mentioned before.
An example for an aralkyl group having from 7 to 60 carbon atoms which is unsubstituted or substituted includes a benzyl group.
Examples of halogen atoms include fluorine, chlorine, bromine, and iodine, with fluorine being preferred.
The group OR20 is preferably a C1-20alkoxy group or a C6-18aryloxy group. Examples of an alkoxy group having 1 to 20 carbon atoms, preferably 1 to 8 carbon atoms, include those having an alkyl portion selected from the alkyl groups mentioned above. Examples of an aryloxy group having 6 to 18 ring carbon atoms include those having an aryl portion selected from the aryl groups mentioned above, for example —OPh.
The group SR21 is preferably a C1-20alkylthio group or a C6-18arylthio group. Examples of an alkylthio group having 1 to 20 carbon atoms, preferably 1 to 8 carbon atoms, include those having an alkyl portion selected from the alkyl groups mentioned above. Examples of an arylthio group having 6 to 18 ring carbon atoms include those having an aryl portion selected from the aryl groups mentioned above, for example —SPh.
The group SiR24R25R26 is preferably a C2-20alkyl and/or C6-18aryl substituted silyl group. Preferred examples of C1-20alkyl and/or C6-18aryl substituted silyl groups include alkylsilyl groups having 1 to 8 carbon atoms in each alkyl residue, preferably 1 to 4 carbon atoms, including trimethylsilyl group, triethylsilyl group, tributylsilyl group, dimethylethylsilyl group, t-butyldimethylsilyl group, propyldimethylsilyl group, dimethylisopropylsilyl group, dimethylpropylsilyl group, dimethylbutylsilyl group, dimethyltertiarybutylsilyl group, diethylisopropylsilyl group, and arylsilyl groups having 6 to 18 ring carbon atoms in each aryl residue, preferably triphenylsilyl group, and alkyl/arylsilyl groups, preferably phenyldimethylsilyl group, diphenylmethylsilyl group, and diphenyltertiarybutylsilyl group, with diphenyltertiarybutylsilyl group and t-butyldimethylsilyl group being preferred.
Examples of a carboxamidalkyl group (alkyl substituted amide group) having 1 to 20 carbon atoms, preferably 1 to 8 carbon atoms include those having an alkyl portion selected from the alkyl groups mentioned above.
Examples of a carboxamidaryl group (aryl substituted amide group) having 6 to 18 carbon atoms, preferably 6 to 13 carbon atoms, include those having an aryl portion selected from the aryl groups mentioned above.
The optional substituents preferably each independently represents an aryl group having from 6 to 18 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 18 ring atoms which is unsubstituted or substituted; an alkyl group having from 1 to 20 carbon atoms which is-unsubstituted or substituted; a cycloalkyl group having from 3 to 20 ring carbon atoms which is unsubstituted or substituted; CN; SiR24R25R26, SR21 or OR20;
More preferably, the optional substituents each independently represents an aryl group having from 6 to 18 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 18 ring atoms which is unsubstituted or substituted; an alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted; a cycloalkyl group having from 3 to 20 ring carbon atoms which is unsubstituted or substituted; or CN;
Most preferably, the optional substituents each independently represents an alkyl group having 1 to 4 carbon atoms which is unsubstituted or substituted; a cycloalkyl group having from 3 to 6 ring carbon atoms which is unsubstituted or substituted; an aryl group having 6 to 13 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 13 ring atoms which is unsubstituted or substituted; or CN.
R20, R21 and R22 each independently represents an aryl group having from 6 to 18 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 18 ring atoms which is unsubstituted or substituted and which is linked via a carbon atom to N or O or S; an alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted; or a cycloalkyl group having from 3 to 20 ring carbon atoms which is unsubstituted or substituted, preferably an aryl group having from 6 to 18 ring carbon atoms which is unsubstituted or substituted; or an alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted.
R24, R25 and R26 represents an aryl group having from 6 to 18 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 18 ring atoms which is unsubstituted or substituted; an alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted; a cycloalkyl group having from 3 to 20 ring carbon atoms which is unsubstituted or substituted.
The optional substituents mentioned above may be further substituted by one or more of the optional substituents mentioned above.
The number of the optional substituents depends on the group which is substituted by said substituent(s). The maximum number of possible substituents is defined by the number of hydrogen atoms present. Preferred are 1, 2, 3, 5, 6, 7, 8 or 9 optional substituents per group which is substituted, more preferred are 1, 2, 3, 5, 5, 6 or 7 optional substituents, most preferred are 1, 2, 3, 4 or 5 optional substituents, further most preferred are 1, 2, 3, 4 or 5 optional substituents, even further most preferred are 1, 2, 3 or 4 optional substituents and even more further most preferred are 1 or 2 optional substituents per group which is substituted. In a further preferred embodiment, some or all of the groups mentioned above are unsubstituted.
In a further preferred embodiment, the total number of substituents in the compound of formula (I) is 0, 1, 2, 3, 4, 5, 6, 7 or 8, preferably 0, 1, 2, 3, 4, 5, or 6, i.e. the remaining residues are hydrogen.
The “carbon number of a to b” in the expression of “substituted or unsubstituted X group having a to b carbon atoms” is the carbon number of the unsubstituted X group and does not include the carbon atom(s) of an optional substituent.
The term “unsubstituted” referred to by “unsubstituted or substituted” means that a hydrogen atom is not substituted by one the groups mentioned above.
An index of 0 in the definition in any formula mentioned above and below means that a hydrogen atom is present at the position defined by said index.
Examples for ring structures formed by two adjacent substituents are shown below:
Preferred examples for ring structures formed by two adjacent substituents are the ring structures (A), (D) and (G), more preferred ring structures formed by two adjacent substituents are
In the heterocyclic compounds represented by formula (I)
In the amino group NAr2Ar3:
More preferably, the the amino group NAr2Ar3 is represented by the following formula (II):
Preferably, 0, 1 or 2 of R27, R28, R29, R30 and R31 and/or 0, 1 or 2 of R32, R33, R34, R35 and R36 each independently represents an aryl group having from 6 to 60 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 60 ring atoms which is unsubstituted or substituted; an alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted, preferably an aryl group having from 6 to 10 ring carbon atoms which is unsubstituted or substituted or an alkyl group having from 1 to 4 carbon atoms,
More preferably, R27, R26, R29, R30, R31, R32, R33, R34, R35 and R36 are hydrogen, an aryl group having from 6 to 10 ring carbon atoms which is unsubstituted or substituted or an alkyl group having from 1 to 4 carbon atoms,
L1 represents a direct bond, an unsubstituted or substituted divalent aromatic hydrocarbon group containing 6 to 30 ring atoms, an unsubstituted or substituted divalent alkyl group having 1 to 20 carbon atoms or an unsubstituted or substituted divalent heteroaromatic group containing 3 to 30 ring atoms;
Ar1 represents an aryl group having from 6 to 60 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 60 ring atoms which is unsubstituted or substituted or an alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted; preferably an aryl group having from 6 to 60 ring carbon atoms which is unsubstituted or substituted or a heteroaryl group having from 5 to 60 ring atoms which is unsubstituted or substituted; more preferably an aryl group having from 6 to 60 ring carbon atoms which is unsubstituted or substituted.
Most preferably, Ar1 represents a group of formula (III)
Preferably, R37, R38, R39, R40 and R41 each independently represents hydrogen, an aryl group having from 6 to 13 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 13 ring atoms which is unsubstituted or substituted; an alkyl group having from 1 to 8 carbon atoms which is unsubstituted or substituted.
In a preferred embodiment of the present invention the group-L1-Ar1 is therefore
wherein L1 is a direct bond and Ar1 is a group of formula (III).
More preferably, 0, 1, 2 or 3, preferably 0, 1 or 2 residues R37, R38, R39, R40 and R41 represents an aryl group having from 6 to 60 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 60 ring atoms which is unsubstituted or substituted; an alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted,
Most preferably, Ar1 represents a group of formula (IIIA)
L2 represents a direct bond, an unsubstituted or substituted divalent aromatic hydrocarbon group containing 6 to 30 ring atoms, an unsubstituted or substituted divalent alkyl group having 1 to 20 carbon atoms or an unsubstituted or substituted divalent heteroaromatic group containing 3 to 30 ring atoms;
R1, R2, R3, R4, R5, R6, R7, R8, R9, R10 and R11 each independently represents hydrogen; an aryl group having from 6 to 60 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 60 ring atoms which is unsubstituted or substituted; an aralkyl group having from 7 to 60 carbon atoms which is unsubstituted or substituted; an alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted; an alkylhalide group having from 1 to 20 carbon atoms which is unsubstituted or substituted; an alkenyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted; an alkynyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted; a cycloalkyl group having from 3 to 20 ring carbon atoms which is unsubstituted or substituted; CN; NO2; OR20; SR21; C(═O)R22; COOR23; SiR24R25R26, NAr2Ar3 or halogen;
Preferably, R1, R2, R3, R4, R5, R6, R7, R8, R9, R10 and R11 each independently represents hydrogen; an aryl group having from 6 to 18 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 18 ring atoms which is unsubstituted or substituted; an aralkyl group having from 7 to 19 carbon atoms which is unsubstituted or substituted; an alkyl group having from 1 to 8 carbon atoms which is unsubstituted or substituted; an alkylhalide group having from 1 to 8 carbon atoms which is unsubstituted or substituted; a cycloalkyl group having from 3 to 18 ring carbon atoms which is unsubstituted or substituted; CN; OR20; SR21; SiR24R25R26, NAr2Ar3 or halogen;
More preferably, R1, R2, R3, R4, R5, R6, R7, R8, R9, R10 and R11 each independently represents hydrogen; an aryl group having from 6 to 18 ring carbon atoms which is unsubstituted or substituted; an alkyl group having from 1 to 8 carbon atoms which is unsubstituted or substituted; a cycloalkyl group having from 3 to 18 ring carbon atoms which is unsubstituted or substituted, NAr2Ar3 or SiR24R25R26;
Preferably, 0, 1, 2, 3 or 4, more preferably 0, 1 or 2 of R1, R2, R3, R4, R5, R6, R7, R8, R9, R10 and R11 each independently represents an aryl group having from 6 to 60 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 60 ring atoms which is unsubstituted or substituted; an aralkyl group having from 7 to 60 carbon atoms which is unsubstituted or substituted; an alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted; an alkylhalide group having from 1 to 20 carbon atoms which is unsubstituted or substituted; an alkenyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted; an alkynyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted; a cycloalkyl group having from 3 to 20 ring carbon atoms which is unsubstituted or substituted; CN; NO2; OR20; SR20; C(═O)R21; COOR22; SiR24R25R26 or halogen;
In one preferred embodiment, R6 and/or R10 each independently represents hydrogen, an aryl group having from 6 to 60 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 60 ring atoms which is unsubstituted or substituted; an aralkyl group having from 7 to 60 carbon atoms which is unsubstituted or substituted; an alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted; an alkylhalide group having from 1 to 20 carbon atoms which is unsubstituted or substituted; an alkenyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted; an alkynyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted; a cycloalkyl group having from 3 to 20 ring carbon atoms which is unsubstituted or substituted; CN; NO2; OR20; SR20; C(═O)R21; COOR22; SiR24R25R26 or halogen;
Most preferably R1, R2, R3, R4, R5, R6, R7, R8, R9, R10 and R11 are hydrogen,
R12, R13, R14, R15, R16, R17, R18 and R19 each independently represents hydrogen; an aryl group having from 6 to 60 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 60 ring atoms which is unsubstituted or substituted; an aralkyl group having from 7 to 60 carbon atoms which is unsubstituted or substituted; an alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted; an alkylhalide group having from 1 to 20 carbon atoms which is unsubstituted or substituted; an alkenyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted; an alkynyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted; a cycloalkyl group having from 3 to 20 ring carbon atoms which is unsubstituted or substituted; CN; NO2; OR20; SR21; C(═O)R22; COOR23; SiR24R25R26 or halogen;
Preferably, R12, R13, R14, R15, R16, R17, R18 and R19 each independently represents hydrogen; an aryl group having from 6 to 18 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 18 ring atoms which is unsubstituted or substituted; an aralkyl group having from 7 to 19 carbon atoms which is unsubstituted or substituted; an alkyl group having from 1 to 8 carbon atoms which is unsubstituted or substituted; an alkylhalide group having from 1 to 8 carbon atoms which is unsubstituted or substituted; a cycloalkyl group having from 3 to 18 ring carbon atoms which is unsubstituted or substituted; CN; OR20; SR21; SiR24R25R26 or halogen;
More preferably, R12, R13, R14, R15, R16, R17, R18 and R19 each independently represents hydrogen; an aryl group having from 6 to 18 ring carbon atoms which is unsubstituted or substituted; an alkyl group having from 1 to 8 carbon atoms which is unsubstituted or substituted; a cycloalkyl group having from 3 to 18 ring carbon atoms which is unsubstituted or substituted or SiR24R25R26;
Preferably, 0, 1 or 2, more preferably 0 or 1 of R12, R13, R14, R15, R16, R17, R18 and R19 each independently represents an aryl group having from 6 to 60 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 60 ring atoms which is unsubstituted or substituted; an aralkyl group having from 7 to 60 carbon atoms which is unsubstituted or substituted; an alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted; an alkylhalide group having from 1 to 20 carbon atoms which is unsubstituted or substituted; an alkenyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted; an alkynyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted; a cycloalkyl group having from 3 to 20 ring carbon atoms which is unsubstituted or substituted; CN; NO2; OR20; SR20; C(═O)R21; COOR22; SiR24R25R26 or halogen;
In one preferred embodiment, R13 represents hydrogen, an aryl group having from 6 to 60 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 60 ring atoms which is unsubstituted or substituted; an aralkyl group having from 7 to 60 carbon atoms which is unsubstituted or substituted; an alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted; an alkylhalide group having from 1 to 20 carbon atoms which is unsubstituted or substituted; an alkenyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted; an alkynyl group having from 2 to 20 carbon atoms which is unsubstituted or substituted; a cycloalkyl group having from 3 to 20 ring carbon atoms which is unsubstituted or substituted; CN; NO2; OR20; SR20; C(═O)R21; COOR22; SiR24R25R26 or halogen; and the remaining residues of R12, R13, R14, R15, R16, R17, R18 and R19 are hydrogen. Preferred residues R12, R13, R14, R15, R16, R17, R18 and R19 which are not hydrogen are mentioned above.
Most preferably R12, R13, R14, R15, R16, R17, R18 and R19 are hydrogen, wherein one of R12, R13, R14, R15, R16, R17, R18 and R19, preferably one of R16, R17, R18 and R19 is a bonding site to L2.
Ra and Rb each independently represents hydrogen; an aryl group having from 6 to 60 ring carbon atoms which is unsubstituted or substituted; a heteroaryl group having from 5 to 60 ring atoms which is unsubstituted or substituted or an alkyl group having from 1 to 20 carbon atoms which is unsubstituted or substituted; preferably an aryl group having from 6 to 13 ring carbon atoms which is unsubstituted or substituted; or an alkyl group having from 1 to 8 carbon atoms which is unsubstituted or substituted; more preferably methyl or phenyl;
wherein the dotted lines are bonding sites.
Most preferred groups
wherein one of R12, R13, R14, R15, R16, R17, R18 and R19 is a bonding site to L2, are represented by the following formula
Preferred compounds of formula (I) are shown in the following, wherein the residues are defined above
More preferred compounds of formula (I) are the following compounds, wherein the residues are defined above
In one embodiment, the compound represented by formula (I) has at least one deuterium atom. For example, one or more hydrogen atoms selected from the group consisting of the following are deuterium atoms:
Any one of the compound explained above may have at least one deuterium atom. In any one of the compound explained above, at least one hydrogen atom in Ar2 or Ar3 may be a deuterium atom.
In any one of the compound explained above, at least one of R27 to R36 may be a deuterium atom.
In any one of the compound explained above, all of R27 to R36 may be deuterium atoms.
Below, examples for compounds of formula (I) are given. In the following specific examples, “D” represents a deuterium atom.
The compounds represented by formula (I) can be synthesized in accordance with the reactions conducted in the examples of the present application, and by using alternative reactions or raw materials suited to an intended product, in analogy to reactions and raw materials known in the art.
The compounds of formula (I) are for example prepared by the following step: Addition of BHaI′3 to the intermediate (IV) whereby the compound of formula (I) is obtained:
The intermediate (IV) is for example prepared by the following steps:
Suitable Pd catalysts are for example Pd(0) complexes with bidentate ligands like dba (dibenzylideneacetone), or Pd(II) salts like PdCl2 or Pd(OAc)2 in combination with bidentate phosphine ligands such as dppf ((diphenylphosphino)ferrocene), dppp ((diphenylphosphino)propane), BINAP (2,2′-Bis(diphenylphosphino)-1,1′-binaphthyl), Xantphos (4,5-Bis(diphenylphosphino)9,9-dimethylxanthene), DPEphos (Bis[(2-diphenylphosphino)phenyl] ether) or Josiphos, or in combination with monodentate phosphine-ligands like di-tert.-butyl-(4-dimethylaminophenyl)phosphine (Amphos), triphenylphosphine, tri-ortho-tolyl phosphine, tri-tertbutylphosphine, tricyclohexylphosphine, 2-Dicyclohexylphosphino-2′,6′-dimethoxybiphenyl (SPhos), 2-Dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (XPhos), or N-heterocyclic carbenes such as 1,3-Bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IPr), 1,3-Dimesitylimidazol-2-ylidene (Imes).
wherein R and R′ are generally substituted or unsubstituted phenyl.
Suitable reaction conditions are known by a person skilled in the art.
Details of all reaction steps and process conditions are mentioned in the examples of the present application.
According to one aspect of the present invention a material for an organic electroluminescence device comprising at least one compound of formula (I) is provided.
According to another aspect of the present invention, an organic electroluminescence device comprising at least one compound of formula (I) is provided.
According to another aspect of the invention, the following organic electroluminescence device is provided: An organic electroluminescence device comprising a cathode, an anode, and one or more organic thin film layers comprising a light emitting layer disposed between the cathode and the anode, wherein at least one layer of the organic thin film layers comprises at least one compound of formula (I).
According to another aspect of the invention an organic electroluminescence device is provided, wherein the light emitting layer comprises at least one compound of formula (I).
According to another aspect of the invention an organic electroluminescence device is provided, wherein the light emitting layer comprises at least one compound of formula (I) as a dopant material and an anthracene compound as a host material.
According to another aspect of the invention an electronic equipment provided with the organic electroluminescence device according to the present invention is provided.
According to another aspect of the invention an emitter material is provided comprising at least one compound of formula (I).
According to another aspect of the invention a light emitting layer is provided comprising at least one host and at least one dopant, wherein the dopant comprises at least one compound of formula (I).
According to another aspect of the invention the use of a compound of formula (I) according to the present invention in an organic electroluminescence device is provided.
In one embodiment, the organic EL device comprises a hole-transporting layer between the anode and the emitting layer.
In one embodiment, the organic EL device comprises an electron-transporting layer between the cathode and the emitting layer.
In the present specification, regarding the “one or more organic thin film layers between the emitting layer and the anode”, if only one organic layer is present between the emitting layer and the anode, it means that layer, and if plural organic layers are present, it means at least one layer thereof. For example, if two or more organic layers are present between the emitting layer and the anode, an organic layer nearer to the emitting layer is called the “hole-transporting layer”, and an organic layer nearer to the anode is called the “hole-injecting layer”. Each of the “hole-transporting layer” and the “hole-injecting layer” may be a single layer or may be formed of two or more layers. One of these layers may be a single layer and the other may be formed of two or more layers.
Similarly, regarding the “one or more organic thin film layers between the emitting layer and the cathode”, if only one organic layer is present between the emitting layer and the cathode, it means that layer, and if plural organic layers are present, it means at least one layer thereof. For example, if two or more organic layers are present between the emitting layer and the cathode, an organic layer nearer to the emitting layer is called the “electron-transporting layer”, and an organic layer nearer to the cathode is called the “electron-injecting layer”. Each of the “electron-transporting layer” and the “electron-injecting layer” may be a single layer or may be formed of two or more layers. One of these layers may be a single layer and the other may be formed of two or more layers.
The “one or more organic thin film layers comprising an emitting layer” mentioned above, preferably the emitting layer, comprises a compound represented by formula (I). The compound represented by formula (I) preferably functions as an emitter material, more preferably as a fluorescent emitter material, most preferably as a blue fluorescent emitter material. By the presence of a compound of formula (I) in the organic EL device, preferably in the emitting layer, organic EL devices characterized by high external quantum efficiencies (EQE) and long lifetimes are provided.
According to another aspect of the invention, an emitting layer of the organic electroluminescence device is provided which comprises at least one compound of formula (I).
Preferably, the emitting layer comprises at least one emitting material (dopant material) and at least one host material, wherein the emitting material is at least one compound of formula (I).
In one embodiment, the host is not selected from CBP (4,4′-Bis-(N-carbazolyl)-biphenyl), mCP, mCBP Sif87 (dibenzo[b,d]thiophen-2-yltriphenylsilane), CzSi, Sif88 (dibenzo[b,d]thiophen-2-yl)diphenylsilane), DPEPO (bis[2-(diphenylphosphino)phenylj ether oxide), 9-[3-(dibenzofuran2-yl)phenyl]-9H-carbazole, 9-[3-(dibenzofuran-2-yl)phenyl]-9H-carbazole, 9-[3-(dibenzothiophen-2-yl)phenyl]-9H-carbazole, 9-[3,5-bis(2-dibenzofuranyl)phenyl]-9H-carbazole, 9-[3,5-bis(2-dibenzothiophenyl)phenyl]-9H-carbazole, T2T (2,4,6-tris(biphenyl-3-yl)-1,3,5-triazine), T3T (2,4,6-tris(triphenyl-3-yl)-1,3,5-triazine) and/or TST (2,4,6-tris(9,9′-spirobifluorene-2-yl)-1,3,5-triazine).
Preferred host materials are substituted or unsubstituted polyaromatic hydrocarbon (PAH) compounds, substituted or unsubstituted polyheteroaromatic compounds, substituted or unsubstituted anthracene compounds, or substituted or unsubstituted pyrene compounds.
More preferably, the organic electroluminescence device according to the present invention comprises in the emitting layer at least one compound of formula (I) as a dopant material and at least one host material selected from the group consisting of substituted or unsubstituted polyaromatic hydrocarbon (PAH) compounds, substituted or unsubstituted polyheteroaromatic compounds, substituted or unsubstituted anthracene compounds, and substituted or unsubstituted pyrene compounds. Preferably, the at least one host is at least one substituted or unsubstituted anthracene compound.
In a further preferred embodiment, the organic electroluminescence device according to the present invention comprises in the emitting layer at least one compound of formula (I) as a dopant material and at least one host material selected from the group consisting of substituted or unsubstituted polyaromatic hydrocarbon (PAH) compounds, substituted or unsubstituted anthracene compounds, and substituted or unsubstituted pyrene compounds. Preferably, the at least one host is at least one substituted or unsubstituted anthracene compound.
According to another aspect of the invention, an emitting layer of the organic electroluminescence device is provided which comprises at least one compound of formula (I) as a dopant material and an anthracene compound as a host material.
Suitable anthracene compounds are represented by the following formula (10):
-L101-Ar101 (31)
Specific examples of each substituent, substituents for “substituted or unsubstituted” and the halogen atom in the compound (10) are the same as those mentioned above.
An explanation will be given on “one or more pairs of two or more adjacent R101 to R101 may form a substituted or unsubstituted, saturated or unsaturated ring”. The “one pair of two or more adjacent R101 to R110” is a combination of R101 and R102, R102 and R103, R103 and R104, R105 and R106, R106 and R107, R107 and R108, R106 and R109, R101 and R102 and R103 or the like, for example.
The substituent in “substituted” in the “substituted or unsubstituted” for the saturated or unsaturated ring is the same as those for “substituted or unsubstituted” mentioned in the formula (10).
The “saturated or unsaturated ring” means, when R101 and R102 form a ring, for example, a ring formed by a carbon atom with which R101 is bonded, a carbon atom with which R102 is bonded and one or more arbitrary elements. Specifically, when a ring is formed by R101 and R102, when an unsaturated ring is formed by a carbon atom with which R101 is bonded, a carbon atom with R102 is bonded and four carbon atoms, the ring formed by R101 and R102 is a benzene ring.
The “arbitrary element” is preferably a C element, a N element, an O element or a S element. In the arbitrary element (C element or N element, for example), atomic bondings that do not form a ring may be terminated by a hydrogen atom, or the like.
The “one or more arbitrary element” is preferably 2 or more and 15 or less, more preferably 3 or more and 12 or less, and further preferably 3 or more and 5 or less arbitrary elements.
For example, R101 and R102 may form a ring, and simultaneously, R105 and R106 may form a ring. In this case, the compound represented by the formula (10) is a compound represented by the following formula (10A), for example:
In one embodiment, R101 to R110 are independently a hydrogen atom, a substituted or unsubstituted alkyl group including 1 to 50 carbon atoms, a substituted or unsubstituted aryl group including 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group including 5 to 50 ring atoms or a group represented by the formula (31).
Preferably, R101 to R110 are independently a hydrogen atom, a substituted or unsubstituted aryl group including 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group including 5 to 50 ring atoms or a group represented by the formula (31).
More preferably, R101 to R110 are independently a hydrogen atom, a substituted or unsubstituted aryl group including 6 to 18 ring carbon atoms, a substituted or unsubstituted heterocyclic group including 5 to 18 ring atoms or a group represented by the formula (31).
Most preferably, at least one of R109 and R110 is a group represented by the formula (31).
Further most preferably, R109 and R110 are independently a group represented by the formula (31).
In one embodiment, the compound (10) is a compound represented by the following formula (10-1):
In one embodiment, the compound (10) is a compound represented by the following formula (10-2):
In one embodiment, the compound (10) is a compound represented by the following formula (10-3):
In one embodiment, the compound (10) is a compound represented by the following formula (10-4):
In one embodiment, the compound (10) is a compound represented by the following formula (10-4A):
In one embodiment, the compound (10) is a compound represented by the following formula (10-6):
In one embodiment, the compound represented by the formula (10-6) is a compound represented by the following formula (10-6H):
In one embodiment, the compound represented by the formulae (10-6) and (10-6H) is a compound represented by the following formula (10-6Ha):
In one embodiment, the compound represented by the formulae (10-6), (10-6H) and (10-6Ha) is a compound represented by the following formula (10-6Ha-1) or (10-6Ha-2):
In one embodiment, the compound (10) is a compound represented by the following formula (10-7):
In one embodiment, the compound (10) is a compound represented by the following formula (10-7H):
In one embodiment, the compound (10) is a compound represented by the following formula (10-8):
In one embodiment, the compound represented by the formula (10-8) is a compound represented by the following formula (10-8H):
In the formula (10-8H), L101 and Ar101 are as defined in the formula (10).
R66′ to R69′ are as defined in the formula (10-4), provided that any one pair of R66′ and R67′ R67′ and R68′ as well as R68′ and R69′ are bonded with each other to form a substituted or unsubstituted, saturated or unsaturated ring. Any one pair of R66′ and R67′ R67′ and R68′ as well as R68′ and R69′ may preferably be bonded with each other to form an unsubstituted benzene ring; and
In one embodiment, as for the compound represented by the formula (10-7), (10-8) or (10-8H), any one pair of R66′ and R67′ R67′ and R68′ as well as R68′ and R69′ are bonded with each other to form a ring represented by the following formula (10-8-1) or (10-8-2), and R66′ to R69′ that do not form the ring represented by the formula (10-8-1) or (10-8-2) do not form a substituted or unsubstituted, saturated or unsaturated ring.
In one embodiment, the compound (10) is a compound represented by the following formula (10-9):
In one embodiment, the compound (10) is selected from the group consisting of compounds represented by the following formulae (10-10-1) to (10-10-4).
In the formulae (10-10-1H) to (10-10-4H), L101A and Ar101A are as defined in the formula (10-3).
In one embodiment, in the compound represented by the formula (10-1), at least one Ar101 is a monovalent group having a structure represented by the following formula (50).
In the formula (50),
One of R151 to R160 is a single bond which bonds with L101.
One or more sets of adjacent two or more of R151 to R154 and one or more sets of adjacent two or more of R155 to R160, which are not a single bond which bonds with L101, form a substituted or unsubstituted, saturated or unsaturated ring by bonding with each other, or do not form a substituted or unsubstituted, saturated or unsaturated ring.
R161 and R162 form a substituted or unsubstituted, saturated or unsaturated ring by bonding with each other, or do not form a substituted or unsubstituted, saturated or unsaturated ring.
R151 and R162 which do not form the substituted or unsubstituted, saturated or unsaturated ring, and R151 to R160 which are not a single bond which bonds with L101 and do not form the substituted or unsubstituted, saturated or unsaturated ring are independently a hydrogen atom, a substituted or unsubstituted alkyl group including 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group including 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group including 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group including 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group including 3 to 50 ring carbon atoms, a substituted or unsubstituted alkoxy group including 1 to 50 carbon atoms, a substituted or unsubstituted alkylene group including 1 to 50 carbon atoms, a substituted or unsubstituted aryloxy group including 6 to 50 ring carbon atoms, a substituted or unsubstituted arylthio group including 6 to 50 ring carbon atoms, a substituted or unsubstituted aralkyl group including 7 to 50 carbon atoms, —Si(R121)(R122)(R123), —C(═O)R124, —COOR125, —N(R126)(R127), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group including 6 to 50 ring carbon atoms, or a substituted or unsubstituted monovalent heterocyclic group including 5 to 50 ring atoms.
Ar101, which is not a monovalent group having the structure represented by the formula (50) is a substituted or unsubstituted aryl group including 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group including 5 to 50 ring atoms.
The position to be the single bond which bonds with L101 in the formula (50) is not particularly limited. In one embodiment, one of R151 to R160 in the formula (50) is a single bond which bonds with L101.
In one embodiment, Ar101 is a monovalent group represented by the following formula (50-R152), (50-R153), (50-R154), (50-R157), or (50-R158).
In the formulas (50-R152), (50-R153), (50-R154), (50-R157), and (50-R158), X151, R151 to R160 are as defined in the formula (50).
As for the compound represented by the formula (10), the following compounds can be given as specific examples. The compound represented by the formula (10) is not limited to these specific examples. In the following specific examples, “D” represents a deuterium atom.
In the case that the emitting layer comprises the compound represented by formula (I) as a dopant and at least one host, wherein preferred hosts are mentioned above, and the host is more preferably at least one compound represented by formula (10), the content of the at least one compound represented by formula (I) is preferably 0.5 mass % to 70 mass %, more preferably 0.5 to 30 mass %, further preferably 1 to 30 mass %, still further preferably 1 to 20 mass %, and particularly preferably 1 to 10 mass %, further particularly preferably 1 to 5 mass %, relative to the entire mass of the emitting layer.
The content of the at least one host, wherein preferred hosts are mentioned above, preferably the at least one compound represented by formula (10) is preferably 30 mass % to 99.9 mass %, more preferably 70 to 99.5 mass %, further preferably 70 to 99 mass %, still further preferably 80 to 99 mass %, and particularly preferably 90 to 99 mass %, further particularly preferably 95 to 99 mass %, relative to the entire mass of the emitting layer.
An explanation will be made on the layer configuration of the organic EL device according to one aspect of the invention.
An organic EL device according to one aspect of the invention comprises a cathode, an anode, and one or more organic thin film layers comprising an emitting layer disposed between the cathode and the anode. The organic layer comprises at least one layer composed of an organic compound. Alternatively, the organic layer is formed by laminating a plurality of layers composed of an organic compound. The organic layer may further comprise an inorganic compound in addition to the organic compound.
At least one of the organic layers is an emitting layer. The organic layer may be constituted, for example, as a single emitting layer, or may comprise other layers which can be adopted in the layer structure of the organic EL device. The layer that can be adopted in the layer structure of the organic EL device is not particularly limited, but examples thereof include a hole-transporting zone (comprising at least one hole-transporting layer and preferably in addition at least one of a hole-injecting layer, an electron-blocking layer, an exciton-blocking layer, etc.), an emitting layer, a spacing layer, and an electron-transporting zone (comprising at least one electron-transporting layer and preferably in addition at least one of an electron-injecting layer, a hole-blocking layer, etc.) provided between the cathode and the emitting layer.
The organic EL device according to one aspect of the invention may be, for example, a fluorescent or phosphorescent monochromatic light emitting device or a fluorescent/phosphorescent hybrid white light emitting device. Preferably, the organic EL device is a fluorescent monochromatic light emitting device, more preferably a blue fluorescent monochromatic light emitting device or a fluorescent/phosphorescent hybrid white light emitting device. Blue fluorescence means a fluorescence at 400 to 500 nm (peak maximum), preferably at 430 nm to 490 nm (peak maximum).
Further, it may be a simple type device having a single emitting unit or a tandem type device having a plurality of emitting units.
The “emitting unit” in the specification is the smallest unit that comprises organic layers, in which at least one of the organic layers is an emitting layer and light is emitted by recombination of injected holes and electrons.
In addition, the “emitting layer” described in the present specification is an organic layer having an emitting function. The emitting layer is, for example, a phosphorescent emitting layer, a fluorescent emitting layer or the like, preferably a fluorescent emitting layer, more preferably a blue fluorescent emitting layer, and may be a single layer or a stack of a plurality of layers.
The emitting unit may be a stacked type unit having a plurality of phosphorescent emitting layers or fluorescent emitting layers. In this case, for example, a spacing layer for preventing excitons generated in the phosphorescent emitting layer from diffusing into the fluorescent emitting layer may be provided between the respective light-emitting layers.
As the simple type organic EL device, a device configuration such as anode/emitting unit/cathode can be given.
Examples for representative layer structures of the emitting unit are shown below. The layers in parentheses are provided arbitrarily.
The layer structure of the organic EL device according to one aspect of the invention is not limited to the examples mentioned above.
For example, when the organic EL device has a hole-injecting layer and a hole-transporting layer, it is preferred that a hole-injecting layer be provided between the hole-transporting layer and the anode. Further, when the organic EL device has an electron-injecting layer and an electron-transporting layer, it is preferred that an electron-injecting layer be provided between the electron-transporting layer and the cathode. Further, each of the hole-injecting layer, the hole-transporting layer, the electron-transporting layer and the electron-injecting layer may be formed of a single layer or be formed of a plurality of layers.
The plurality of phosphorescent emitting layer, and the plurality of the phosphorescent emitting layer and the fluorescent emitting layer may be emitting layers that emit mutually different colors. For example, the emitting unit (f) may include a hole-transporting layer/first phosphorescent layer (red light emission)/second phosphorescent emitting layer (green light emission)/spacing layer/fluorescent emitting layer (blue light emission)/electron-transporting layer.
An electron-blocking layer may be provided between each light emitting layer and the hole-transporting layer or the spacing layer. Further, a hole-blocking layer may be provided between each emitting layer and the electron-transporting layer. By providing the electron-blocking layer or the hole-blocking layer, it is possible to confine electrons or holes in the emitting layer, thereby to improve the recombination probability of carriers in the emitting layer, and to improve light emitting efficiency.
As a representative device configuration of a tandem type organic EL device, for example, a device configuration such as anode/first emitting unit/intermediate layer/second emitting unit/cathode can be given.
The first emitting unit and the second emitting unit are independently selected from the above-mentioned emitting units, for example.
The intermediate layer is also generally referred to as an intermediate electrode, an intermediate conductive layer, a charge generating layer, an electron withdrawing layer, a connecting layer, a connector layer, or an intermediate insulating layer. The intermediate layer is a layer that supplies electrons to the first emitting unit and holes to the second emitting unit, and can be formed from known materials.
Hereinbelow, an explanation will be made on function, materials, etc. of each layer constituting the organic EL device described in the present specification.
The substrate is used as a support of the organic EL device. The substrate preferably has a light transmittance of 50% or more in the visible light region with a wavelength of 400 to 700 nm, and a smooth substrate is preferable. Examples of the material of the substrate include soda-lime glass, aluminosilicate glass, quartz glass, plastic and the like. As a substrate, a flexible substrate can be used. The flexible substrate means a substrate that can be bent (flexible), and examples thereof include a plastic substrate and the like. Specific examples of the material for forming the plastic substrate include polycarbonate, polyallylate, polyether sulfone, polypropylene, polyester, polyvinyl fluoride, polyvinyl chloride, polyimide, polyethylene naphthalate and the like. Also, an inorganic vapor deposited film can be used.
As the anode, for example, it is preferable to use a metal, an alloy, a conductive compound, a mixture thereof or the like and having a high work function (specifically, 4.0 eV or more). Specific examples of the material of the anode include indium oxide-tin oxide (ITO: Indium Tin Oxide), indium oxide-tin oxide containing silicon or silicon oxide, indium oxide-zinc oxide, indium oxide containing tungsten oxide or zinc oxide, graphene and the like. In addition, it is also possible to use gold, silver, platinum, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, titanium, and nitrides of these metals (e.g. titanium oxide).
The anode is normally formed by depositing these materials on the substrate by a sputtering method. For example, indium oxide-zinc oxide can be formed by a sputtering method by using a target in which 1 to 10 mass % zinc oxide is added relative to indium oxide. Further, indium oxide containing tungsten oxide or zinc oxide can be formed by a sputtering method by using a target in which 0.5 to 5 mass % of tungsten oxide or 0.1 to 1 mass % of zinc oxide is added relative to indium oxide.
As other methods for forming the anode, a vacuum deposition method, a coating method, an inkjet method, a spin coating method or the like can be given. When silver paste or the like is used, it is possible to use a coating method, an inkjet method or the like.
The hole-injecting layer formed in contact with the anode is formed by using a material that allows easy hole injection regardless of the work function of the anode. For this reason, in the anode, it is possible to use a common electrode material, e.g. a metal, an alloy, a conductive compound and a mixture thereof. Specifically, a material having a small work function such as alkaline metals such as lithium and cesium; alkaline earth metals such as calcium and strontium; alloys containing these metals (for example, magnesium-silver and aluminum-lithium); rare earth metals such as europium and ytterbium; and an alloy containing rare earth metals.
The hole-transporting layer is an organic layer that is formed between the emitting layer and the anode, and has a function of transporting holes from the anode to the emitting layer. If the hole-transporting layer is composed of plural layers, an organic layer that is nearer to the anode may often be defined as the hole-injecting layer. The hole-injecting layer has a function of injecting holes efficiently to the organic layer unit from the anode. Said hole injection layer is generally used for stabilizing hole injection from anode to hole transporting layer which is generally consist of organic materials. Organic material having good contact with anode or organic material with p-type doping is preferably used for the hole injection layer.
p-doping usually consists of one or more p-dopant materials and one or more matrix materials. Matrix materials preferably have shallower HOMO level and p-dopant preferably have deeper LUMO level to enhance the carrier density of the layer. Specific examples for p-dopants are the below mentioned acceptor materials. Suitable matrix materials are the hole transport materials mentioned below, preferably aromatic or heterocyclic amine compounds.
Acceptor materials, or fused aromatic hydrocarbon materials or fused heterocycles which have high planarity, are preferably used as p-dopant materials for the hole injection layer. Specific examples for acceptor materials are, quinone compounds with one or more electron withdrawing groups, such as F4TCNQ (2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane), and 1,2,3-tris[(cyano)(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropane; hexa-azatriphenylene compounds with one or more electron withdrawing groups, such as hexa-azatriphenylene-hexanitrile; aromatic hydrocarbon compounds with one or more electron withdrawing groups; and aryl boron compounds with one or more electron withdrawing groups. Preferred p-dopants are quinone compounds with one or more electron withdrawing groups, such as F4TCNQ, 1,2,3-Tris[(cyano)(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropane.
The ratio of the p-type dopant is preferably less than 20% of molar ratio, more preferably less than 10%, such as 1%, 3%, or 5%, related to the matrix material.
The hole transporting layer is generally used for injecting and transporting holes efficiently, and aromatic or heterocyclic amine compounds are preferably used.
Specific examples for compounds for the hole transporting layer are represented by the general formula (H),
wherein Ar1′ to Ar3′ each independently represents substituted or unsubstituted aryl group having 5 to 50 carbon atoms or substituted or unsubstituted heterocyclic group having 5 to 50 cyclic atoms, preferably phenyl group, biphenyl group, terphenyl group, naphthyl group, phenanthryl group, triphenylenyl group, fluorenyl group, spirobifluorenyl group, indenofluorenyl group, carbazolyl group, dibenzofuranyl group, dibenzothiophenyl group, carbazole substituted aryl group, dibenzofuran substituted aryl group or dibenzothiophene substituted aryl group; two or more substituents selected among Ar1′ to Ar3′ may be bonded to each other to form a ring structure, such as a carbazole ring structure, or a acridane ring structure.
Preferably, at least one of Ar1′ to Ar3′ have additional one aryl or heterocyclic amine substituent, more preferably Arn has an additional aryl amino substituent, at the case of that it is preferable that Ar1′ represents substituted or unsubstituted biphenylene group, substituted or unsubstituted fluorenylene group. Specific examples for the hole transport material are
and the like.
A second hole transporting layer is preferably inserted between the first hole transporting layer and the emitting layer to enhance device performance by blocking excess electrons or excitons. Specific examples for second hole transporting layer are the same as for the first hole transporting layer. It is preferred that second hole transporting layer has higher triplet energy to block triplet excitons, especially for phosphorescent devices, such as bicarbazole compounds, biphenylamine compounds, triphenylenyl amine compounds, fluorenyl amine compounds, carbazole substituted arylamine compounds, dibenzofuran substituted arylamine compounds, and dibenzothiophene substituted arylamine compounds.
The emitting layer is a layer containing a substance having a high emitting property (emitter material or dopant material). As the dopant material, various materials can be used. For example, a fluorescent emitting compound (fluorescent dopant), a phosphorescent emitting compound (phosphorescent dopant) or the like can be used. A fluorescent emitting compound is a compound capable of emitting light from the singlet excited state, and an emitting layer containing a fluorescent emitting compound is called a fluorescent emitting layer. Further, a phosphorescent emitting compound is a compound capable of emitting light from the triplet excited state, and an emitting layer containing a phosphorescent emitting compound is called a phosphorescent emitting layer.
Preferably, the emitting layer in the organic EL device of the present application comprises a compound of formula (I) as a dopant material.
The emitting layer preferably comprises at least one dopant material and at least one host material that allows it to emit light efficiently. In some literatures, a dopant material is called a guest material, an emitter or an emitting material. In some literatures, a host material is called a matrix material.
A single emitting layer may comprise plural dopant materials and plural host materials. Further, plural emitting layers may be present.
In the present specification, a host material combined with the fluorescent dopant is referred to as a “fluorescent host” and a host material combined with the phosphorescent dopant is referred to as the “phosphorescent host”. Note that the fluorescent host and the phosphorescent host are not classified only by the molecular structure. The phosphorescent host is a material for forming a phosphorescent emitting layer containing a phosphorescent dopant, but does not mean that it cannot be used as a material for forming a fluorescent emitting layer. The same can be applied to the fluorescent host.
In one embodiment, it is preferred that the emitting layer comprises the compound represented by formula (I) according to the present invention (hereinafter, these compounds may be referred to as the “compound (1)”). More preferably, it is contained as a dopant material. Further, it is preferred that the compound (1) be contained in the emitting layer as a fluorescent dopant. Even further, it is preferred that the compound (1) be contained in the emitting layer as a blue fluorescent dopant.
In one embodiment, no specific restrictions are imposed on the content of the compound (1) as the dopant material in the emitting layer. In respect of sufficient emission and concentration quenching, the content is preferably 0.5 to 70 mass %, more preferably 0.8 to 30 mass %, further preferably 1 to 30 mass %, still further preferably 1 to 20 mass %, and particularly preferably 1 to 10 mass %, further particularly preferably 1 to 5 mass %, even further particularly preferably 2 to 4 mass %, related to the mass of the emitting layer.
As a fluorescent dopant other than the compound (1), a fused polycyclic aromatic compound, a styrylamine compound, a fused ring amine compound, a boron-containing compound, a pyrrole compound, an indole compound, a carbazole compound can be given, for example. Among these, a fused ring amine compound, a boron-containing compound, carbazole compound is preferable.
As the fused ring amine compound, a diaminopyrene compound, a diaminochrysene compound, a diaminoanthracene compound, a diaminofluorene compound, a diaminofluorene compound with which one or more benzofuro skeletons are fused, or the like can be given.
As the boron-containing compound, a pyrromethene compound, a triphenylborane compound or the like can be given.
As a blue fluorescent dopant, pyrene compounds, styrylamine compounds, chrysene compounds, fluoranthene compounds, fluorene compounds, diamine compounds, triarylamine compounds and the like can be given, for example. Specifically, N,N′-bis[4-(9H-carbazol-9-yl)phenyl]-N,N′-diphenylstilbene-4,4′-diamine (abbreviation: YGA2S), 4-(9H-carbazol-9-yl)-4′-(10-phenyl-9-anthryl)triphenyamine (abbreviation: YGAPA), 4-(10-phenyl-9-anthryl)-4′-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBAPA) or the like can be given.
As a green fluorescent dopant, an aromatic amine compound or the like can be given, for example. Specifically, N-(9,10-diphenyl-2-anthryl)-N,9-diphenyl-9H-carbazole-3-amine (abbreviation: 2PCAPA), N-[9,10-bis(1,1′-biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H-carbazole-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N′,N′-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10-bis(1,1′-biphenyl-2-yl)-2-anthryl]-N,N′,N′-triphenyl-1,4-phenylenediamine (abbreviation: 2DPABPhA), N-[9,10-bis(1,1′-biphenyl-2-yl)]-N-[4-(9H-carbazole-9-yl)phenyl]-N-phenylanthracene-2-amine (abbreviation: 2YGABPhA), N,N,9-triphenylanthracene9-amine (abbreviation: DPhAPhA) or the like can be given, for example.
As a red fluorescent dopant, a tetracene compound, a diamine compound or the like can be given. Specifically, N,N,N′,N′-tetrakis(4-methylphenyl)tetracene-5,11-diamine (abbreviation: pmPhTD), 7,14-diphenyl-N,N,N′,N′-tetrakis(4-methylphenyl)acenaphtho[1,2-a]fluoranthene-3,10-diamine (abbreviation: p-mPhAFD) or the like can be given.
As a phosphorescent dopant, a phosphorescent emitting heavy metal complex and a phosphorescent emitting rare earth metal complex can be given.
As the heavy metal complex, an iridium complex, an osmium complex, a platinum complex or the like can be given. The heavy metal complex is for example an ortho-metalated complex of a metal selected from iridium, osmium and platinum.
Examples of rare earth metal complexes include terbium complexes, europium complexes and the like. Specifically, tris(acetylacetonate)(monophenanthroline)terbium(III) (abbreviation: Tb(acac)3(Phen)), tris(1,3-diphenyl-1,3-propandionate)(monophenanthroline)europium(III) (abbreviation: Eu(DBM)3(Phen)), tris[1-(2-thenoyl)-3,3,3-trifluoroacetonate](monophenanthroline)europium(III) (abbreviation: Eu(TTA)3(Phen)) or the like can be given. These rare earth metal complexes are preferable as phosphorescent dopants since rare earth metal ions emit light due to electronic transition between different multiplicity.
As a blue phosphorescent dopant, an iridium complex, an osmium complex, a platinum complex, or the like can be given, for example. Specifically, bis[2-(4′,6′-difluorophenyl)pyridinateN,C2′]iridium(III) tetrakis(1-pyrazolyl)borate (abbreviation: Flr6), bis[2-(4′,6′-difluorophenyl) pyridinato-N,C2′]iridium(III) picolinate (abbreviation: Ir(CF3ppy)2(pic)), bis[2-(4′,6′-difluorophenyl)pyridinato-N,C2′]iridium(III) acetylacetonate (abbreviation: Flracac) or the like can be given.
As a green phosphorescent dopant, an iridium complex or the like can be given, for example. Specifically, tris(2-phenylpyridinato-N,C2′) iridium(III) (abbreviation: Ir(ppy)3), bis(1,2-diphenyl1H-benzimidazolato)iridium(III) acetylacetonate (abbreviation: Ir(pbi)2(acac)), bis(benzo[h]quinolinato)iridium(III) acetylacetonate (abbreviation: Ir(bzq)2(acac)) or the like can be given.
As a red phosphorescent dopant, an iridium complex, a platinum complex, a terbium complex, a europium complex or the like can be given. Specifically, bis[2-(2′-benzo[4,5-α]thienyl)pyridinatoN,C3′]iridium(III) acetylacetonate (abbreviation: Ir(btp)2(acac)), bis(1-phenylisoquinolinatoN,C2′)iridium(III) acetylacetonate (abbreviation: Ir(piq)2(acac)), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(II) (abbreviation: Ir(Fdpq)2(acac)), 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin platinum(II) (abbreviation PtOEP) or the like can be given.
As mentioned above, the emitting layer preferably comprises at least one compound (1) as a dopant.
As host material, metal complexes such as aluminum complexes, beryllium complexes and zinc complexes; heterocyclic compounds such as indole compounds, pyridine compounds, pyrimidine compounds, triazine compounds, quinoline compounds, isoquinoline compounds, quinazoline compounds, dibenzofuran compounds, dibenzothiophene compounds, oxadiazole compounds, benzimidazole compounds, phenanthroline compounds; fused polyaromatic hydrocarbon (PAH) compounds such as a naphthalene compound, a triphenylene compound, a carbazole compound, an anthracene compound, a phenanthrene compound, a pyrene compound, a chrysene compound, a naphthacene compound, a fluoranthene compound; and aromatic amine compound such as triarylamine compounds and fused polycyclic aromatic amine compounds can be given, for example. Plural types of host materials can be used in combination.
As a fluorescent host, a compound having a higher singlet energy level than a fluorescent dopant is preferable. For example, a heterocyclic compound, a fused aromatic compound or the like can be given. As a fused aromatic compound, an anthracene compound, a pyrene compound, a chrysene compound, a naphthacene compound or the like are preferable. An anthracene compound is preferentially used as blue fluorescent host.
In the case that compound (1) is employed as at least one dopant material, preferred host materials are substituted or unsubstituted polyaromatic hydrocarbon (PAH) compounds, substituted or unsubstituted polyheteroaromatic compounds, substituted or unsubstituted anthracene compounds, or substituted or unsubstituted pyrene compounds, preferably substituted or unsubstituted anthracene compounds or substituted or unsubstituted pyrene compounds, more preferably substituted or unsubstituted anthracene compounds, most preferably anthracene compounds represented by formula (10), as mentioned above.
As a phosphorescent host, a compound having a higher triplet energy level as compared with a phosphorescent dopant is preferable. For example, a metal complex, a heterocyclic compound, a fused aromatic compound or the like can be given. Among these, an indole compound, a carbazole compound, a pyridine compound, a pyrimidine compound, a triazine compound, a quinolone compound, an isoquinoline compound, a quinazoline compound, a dibenzofuran compound, a dibenzothiophene compound, a naphthalene compound, a triphenylene compound, a phenanthrene compound, a fluoranthene compound or the like can be given.
The electron-transporting layer is an organic layer that is formed between the emitting layer and the cathode and has a function of transporting electrons from the cathode to the emitting layer. When the electron-transporting layer is formed of plural layers, an organic layer or an inorganic layer that is nearer to the cathode is often defined as the electron injecting layer (see for example layer 8 in
According to one embodiment, it is preferred that the electron-transporting layer further comprises one or more layer(s) like a second electron-transporting layer, an electron injection layer to enhance efficiency and lifetime of the device, a hole blocking layer, an exciton blocking layer or a triplet blocking layer.
According to one embodiment, it is preferred that an electron-donating dopant be contained in the interfacial region between the cathode and the emitting unit. Due to such a configuration, the organic EL device can have an increased luminance or a long life. Here, the electron-donating dopant means one having a metal with a work function of 3.8 eV or less. As specific examples thereof, at least one selected from an alkali metal, an alkali metal complex, an alkali metal compound, an alkaline earth metal, an alkaline earth metal complex, an alkaline earth metal compound, a rare earth metal, a rare earth metal complex and a rare earth metal compound or the like can be mentioned.
As the alkali metal, Li (work function: 2.9 eV), Na (work function: 2.36 eV), K (work function: 2.28 eV), Rb (work function: 2.16 eV), Cs (work function: 1.95 eV) and the like can be given. One having a work function of 2.9 eV or less is particularly preferable. Among them, K, Rb and Cs are preferable. Rb or Cs is further preferable. Cs is most preferable. As the alkaline earth metal, Ca (work function: 2.9 eV), Sr (work function: 2.0 eV to 2.5 eV), Ba (work function: 2.52 eV) and the like can be given. One having a work function of 2.9 eV or less is particularly preferable. As the rare-earth metal, Sc, Y, Ce, Tb, Yb and the like can be given. One having a work function of 2.9 eV or less is particularly preferable.
Examples of the alkali metal compound include an alkali oxide such as Li2O, Cs2O or K2O, and an alkali halide such as LiF, NaF, CsF and KF. Among them, LiF, Li2O and NaF are preferable. Examples of the alkaline earth metal compound include BaO, SrO, CaO, and mixtures thereof such as BaxSr1-xO (0<x<1) and BaxCa1-xO (0<x<1). Among them, BaO, SrO and CaO are preferable. Examples of the rare earth metal compound include YbF3, ScF3, ScO3, Y2O3, Ce2O3, GdF3 and TbF3. Among these, YbF3, ScF3 and TbF3 are preferable.
The alkali metal complexes, the alkaline earth metal complexes and the rare earth metal complexes are not particularly limited as long as they contain, as a metal ion, at least one of alkali metal ions, alkaline earth metal ions, and rare earth metal ions. Meanwhile, preferred examples of the ligand include, but are not limited to, quinolinol, benzoquinolinol, acridinol, phenanthridinol, hydroxyphenyloxazole, hydroxyphenylthiazole, hydroxydiaryloxadiazole, hydroxydiarylthiadiazole, hydroxyphenylpyridine, hydroxyphenylbenzimidazole, hydroxybenzotriazole, hydroxyfluborane, bipyridyl, phenanthroline, phthalocyanine, porphyrin, cyclopentadiene, β-diketones, and azomethines.
Regarding the addition form of the electron-donating dopant, it is preferred that the electron-donating dopant be formed in a shape of a layer or an island in the interfacial region. A preferred method for the formation is a method in which an organic compound (a light emitting material or an electron-injecting material) for forming the interfacial region is deposited simultaneously with deposition of the electron-donating dopant by a resistant heating deposition method, thereby dispersing the electron-donating dopant in the organic compound.
In a case where the electron-donating dopant is formed into the shape of a layer, the light-emitting material or electron-injecting material which serves as an organic layer in the interface is formed into the shape of a layer. After that, a reductive dopant is solely deposited by the resistant heating deposition method to form a layer preferably having a thickness of from 0.1 nm to 15 nm. In a case where the electron-donating dopant is formed into the shape of an island, the emitting material or the electron-injecting material which serves as an organic layer in the interface is formed into the shape of an island. After that, the electron-donating dopant is solely deposited by the resistant heating deposition method to form an island preferably having a thickness of from 0.05 nm to 1 nm. As the electron-transporting material used in the electron-transporting layer other than a compound of the formula (I), an aromatic heterocyclic compound having one or more hetero atoms in the molecule may preferably be used. In particular, a nitrogen-containing heterocyclic compound is preferable.
According to one embodiment, it is preferable that the electron-transporting layer comprises a nitrogen-containing heterocyclic metal chelate.
According to the other embodiment, it is preferable that the electron-transporting layer comprises a substituted or unsubstituted nitrogen containing heterocyclic compound. Specific examples of preferred heterocyclic compounds for the electron-transporting layer are, 6-membered azine compounds; such as pyridine compounds, pyrimidine compounds, triazine compounds, pyrazine compounds, preferably pyrimidine compounds or triazine compounds; 6-membered fused azine compounds, such as quinolone compounds, isoquinoline compounds, quinoxaline compounds, quinazoline compounds, phenanthroline compounds, benzoquinoline compounds, benzoisoquinoline compounds, dibenzoquinoxaline compounds, preferably quinolone compounds, isoquinoline compounds, phenanthroline compounds; 5-membered heterocyclic compounds, such as imidazole compounds, oxazole compounds, oxadiazole compounds, triazole compounds, thiazole compounds, thiadiazole compounds; fused imidazole compounds, such as benzimidazole compounds, imidazopyridine compounds, naphthoimidazole compounds, benzimidazophenanthridine compounds, benzimidzobenzimidazole compounds, preferably benzimidazole compounds, imidazopyridine compounds or benzimidazophenanthridine compounds.
According to another embodiment, it is preferable the electron-transporting layer comprises a phosphine oxide compound represented as Arp1Arp2ArP3P═O.
Arp1 to Arp3 are the substituents of phosphor atom and each independently represent substituted or unsubstituted above mentioned aryl group or substituted or unsubstituted above mentioned heterocyclic group.
According to another embodiment, it is preferable that the electron-transporting layer comprises aromatic hydrocarbon compounds. Specific examples of preferred aromatic hydrocarbon compounds for the electron-transporting layer are, oligo-phenylene compounds, naphthalene compounds, fluorene compounds, fluoranthenyl group, anthracene compounds, phenanthrene compounds, pyrene compounds, triphenylene compounds, benzanthracene compounds, chrysene compounds, benzphenanthrene compounds, naphthacene compounds, and benzochrysene compounds, preferably anthracene compounds, pyrene compounds and fluoranthene compounds.
For the cathode, a metal, an alloy, an electrically conductive compound, and a mixture thereof, each having a small work function (specifically, a work function of 3.8 eV or less) are preferably used. Specific examples of a material for the cathode include an alkali metal such as lithium and cesium; an alkaline earth metal such as magnesium, calcium, and strontium; aluminum, an alloy containing these metals (for example, magnesium-silver, aluminum-lithium); a rare earth metal such as europium and ytterbium; and an alloy containing a rare earth metal.
The cathode is usually formed by a vacuum vapor deposition or a sputtering method. Further, in the case of using a silver paste or the like, a coating method, an inkjet method, or the like can be employed.
Moreover, various electrically conductive materials such as silver, ITO, graphene, indium oxide-tin oxide containing silicon or silicon oxide, selected independently from the work function, can be used to form a cathode. These electrically conductive materials are made into films using a sputtering method, an inkjet method, a spin coating method, or the like.
In the organic EL device, pixel defects based on leakage or a short circuit are easily generated since an electric field is applied to a thin film. In order to prevent this, it is preferred to insert an insulating thin layer between a pair of electrodes. Examples of materials used in the insulating layer include aluminum oxide, lithium fluoride, lithium oxide, cesium fluoride, cesium oxide, magnesium oxide, magnesium fluoride, calcium oxide, calcium fluoride, aluminum nitride, titanium oxide, silicon oxide, germanium oxide, silicon nitride, boron nitride, molybdenum oxide, ruthenium oxide, and vanadium oxide. A mixture thereof may be used in the insulating layer, and a laminate of a plurality of layers that include these materials can be also used for the insulating layer.
A spacing layer is a layer provided between a fluorescent emitting layer and a phosphorescent emitting layer when a fluorescent emitting layer and a phosphorescent emitting layer are stacked in order to prevent diffusion of excitons generated in the phosphorescent emitting layer to the fluorescent emitting layer or in order to adjust the carrier balance. Further, the spacing layer can be provided between the plural phosphorescent emitting layers.
Since the spacing layer is provided between the emitting layers, the material used for the spacing layer is preferably a material having both electron-transporting capability and hole-transporting capability. In order to prevent diffusion of the triplet energy in adjacent phosphorescent emitting layers, it is preferred that the spacing layer have a triplet energy of 2.6 eV or more. As the material used for the spacing layer, the same materials as those used in the above-mentioned hole-transporting layer can be given.
An electron-blocking layer, a hole-blocking layer, an exciton (triplet)-blocking layer, and the like may be provided in adjacent to the emitting layer.
The electron-blocking layer has a function of preventing leakage of electrons from the emitting layer to the hole-transporting layer. The hole-blocking layer has a function of preventing leakage of holes from the emitting layer to the electron-transporting layer. In order to improve hole blocking capability, a material having a deep HOMO level is preferably used. The exciton-blocking layer has a function of preventing diffusion of excitons generated in the emitting layer to the adjacent layers and confining the excitons within the emitting layer. In order to improve triplet block capability, a material having a high triplet level is preferably used.
The method for forming each layer of the organic EL device of the invention is not particularly limited unless otherwise specified. A known film-forming method such as a dry film-forming method, a wet film-forming method or the like can be used. Specific examples of the dry film-forming method include a vacuum deposition method, a sputtering method, a plasma method, an ion plating method, and the like. Specific examples of the wet film-forming method include various coating methods such as a spin coating method, a dipping method, a flow coating method, an inkjet method, and the like.
The film thickness of each layer of the organic EL device of the invention is not particularly limited unless otherwise specified. If the film thickness is too small, defects such as pinholes are likely to occur to make it difficult to obtain a sufficient luminance. If the film thickness is too large, a high driving voltage is required to be applied, leading to a lowering in efficiency. In this respect, the film thickness is preferably 0.1 nm to 10 μm, and more preferably 5 nm to 0.2 μm.
The present invention further relates to an electronic equipment (electronic apparatus) comprising the organic electroluminescence device according to the present application. Examples of the electronic apparatus include display parts such as an organic EL panel module; display devices of television sets, mobile phones, smart phones, and personal computer, and the like; and emitting devices of a lighting device and a vehicle lighting device.
Next, the invention will be explained in more detail in accordance with the following synthesis examples, examples, and comparative examples, which should not be construed as limiting the scope of the invention.
The percentages and ratios mentioned in the examples below—unless stated otherwise—are % by weight and weight ratios.
All experiments are carried out in protective gas atmosphere.
42.0 mL (249.0 mmol) of 2,2,6,6-tetramethylpiperidine was dissolved in 250 mL of THF, and the solution was cooled to −78° C. before 100 mL (250 mmol) of 2.5M n-butyllithium in hexane was added dropwise via a cannula for 30 min. The solution was stirred at −78° C. for 30 min. 67.0 mL (290.5 mmol) of triisopropyl borate was added slowly within 30 min, and the mixture was stirred at −78° C. for 1 hour before a solution of 24.24 g (83.0 mmol) of 1,2-dibromo-4-(tert-butyl)benzene in 50 mL of THF was added dropwise within 45 min at −78° C. Then, the mixture was warmed to room temperature overnight. The reaction mixture was poured into 300 mL of ice-cold 1 N HCl, and the aqueous layer was extracted with ethylacetate. The organic layer was washed with brine, dried over magnesium sulfate, filtered and concentrated. The crude product was used for the next reaction without purification.
LC-MS: 335 [M−1]−
27.86 g (82.96 mmol) of Intermediate 1-1 and 1.63 g (16.59 mmol) of potassium acetate were suspended in 332 mL of acetonitrile. Then, 22.4 g (99.55 mmol) of N-iodosuccinimide was added to the suspension at room temperature, and the mixture was stirred overnight. The reaction mixture was quenched with 300 mL of 10% sodium sulfite. The aqueous layer was extracted with toluene, and the organic layer was washed with brine, dried over magnesium sulfate, filtered and concentrated. The crude product was purified by silica-gel column chromatography using heptane as eluent to give 22.1 g (61% yield) of Intermediate 1-2 as a white solid. 1H-NMR (300 MHz, CD2Cl2) δ 7.84 (d, J=2.2 Hz, 1H), 7.63 (d, J=2.2 Hz, 1H), 1.28 (s, 9H).
12.41 g (29.70 mmol) of Intermediate 1-2, 7.96 g (28.28 mmol) of bis(4-(tert-butyl)phenylamine, and 3.81 g (39.60 mmol) of sodium tert-butoxide were added to 190 mL of toluene. The suspension was degassed using 3 freeze-pump-thaw cycles, and 777 mg (0.85 mmol) of tris(dibenzylideneacetone)dipalladium(0) and 982 mg (1.70 mmol) of xantphos were added to the reaction mixture. After two additional freeze-pump-thaw cycles followed by replacement with argon gas, the reaction mixture was heated to 90° C. for 19 hours. The reaction was cooled to room temperature and diluted with toluene and water. The organic extracts were washed with water and dried over magnesium sulfate, filtered, and the solution was concentrated. The residue was purified by silica-gel column chromatography using cyclohexane as eluent to give 8.62 g (53% yield) of Intermediate 1-3 as a white solid.
LC-MS: 572 [M+1]+
9.5 g (16.62 mmol) of Intermediate 1-3, 4.54 g (17.46 mmol) of N1,N1-diphenyl-1,3-benzenediamine, and 4.12 g (41.6 mmol) of sodium tert-butoxide were added to 190 mL of toluene. The suspension was degassed using 3 freeze-pump-thaw cycles, and 156 mg (0.17 mmol) of tris(dibenzylideneacetone)dipalladium(0) and 423 mg (0.67 mmol) of BINAP were added to the reaction mixture. After two additional freeze-pump-thaw cycles followed by replacement with argon gas, the reaction mixture was heated to 90° C. for 2 hours. The reaction was cooled to room temperature and diluted with toluene and water. The organic extracts were washed with water and dried over magnesium sulfate, filtered, and the solution was concentrated. The residue was purified by silica-gel column chromatography using a mixed solvent of heptane and dichloromethane as eluent to give 11.8 g (95% yield) of Intermediate 1-4 as a white foam.
LC-MS: 750 [M+1]+
9.61 g (12.80 mmol) of Intermediate 1-4, 4.60 g (14.08 mmol) of 2-iodo-9,9-dimethyl-9H-fluorene, and 3.17 g (32.0 mmol) of sodium tert-butoxide were added to 128 mL of toluene. The suspension was degassed using 3 freeze-pump-thaw cycles, and 120 mg (0.13 mmol) of tris(dibenzylideneacetone)dipalladium(0) and 152 mg (0.51 mmol) of tri-tert-butylphosphonium tertrafluoroborate were added to the reaction mixture. After two additional freeze-pump-thaw cycles followed by replacement with argon gas, the reaction mixture was heated to 80° C. for 2 hours. The reaction was cooled to room temperature and diluted with toluene and water. The organic extracts were washed with water and dried over magnesium sulfate, filtered, and the solution was concentrated. The residue was purified by silica-gel column chromatography using a mixed solvent of heptane and dichloromethane as eluent to give 10.36 g (86% yield) of Intermediate 1-5 as a white solid.
LC-MS: 942 [M+1]+
2.06 g (2.18 mmol) of Intermediate 1-5 was added to 62 mL of tert-butylbenzene, and the solution was bubbled with argon. 2.3 mL of 1.9 M tert-butyllithium in pentane was added dropwise to the solution at 0° C., and the reaction mixture was stirred at 0° C. for 1 hour. Then the reaction mixture was warmed to room temperature, and it was stirred for 2 hours. The reaction mixture was cooled at −30° C., and 0.41 mL (4.37 mmol) of tribromoborane was added, then the reaction mixture was stirred for 45 min. After the reaction mixture was warmed to 0° C., 1.9 mL (10.92 mmol) of N-ethyl-N-isopropylpropan-2-amine was added, and then the mixture was heated to 145° C. After 45 min, the reaction mixture was cooled at room temperature, and quenched with 10% sodium acetate aqueous solution. The mixture was diluted with ethylacetate, and the aqueous layer was extracted with ethylacetate. The organic layer was washed with water and brine, and dried over magnesium sulfate. It was filtered and concentrated. The residue was purified by silica-gel column chromatography using a mixed solvent of heptane and dichloromethane as eluent to give 0.67 g (35% yield) of Compound 1 as a yellow powder.
LC-MS: 872 [M+1]+
27.86 g (155.39 mmol) of N-(Phenyl-2,3,4,5,6-d5)benzen-2,3,4,5,6-d5-amine, 36.10 g (178.70 mmol) of 1-bromo-3-nitrobenzene, and 20.91 g (217.55 mmol) of sodium tert-butoxide were added to 622 mL of toluene. The suspension was degassed using 3 freeze-pump-thaw cycles, and 2.85 g (3.11 mmol) of tris(dibenzylideneacetone)dipalladium(0) and 3.61 g (12.43 mmol) of tri-tert-butylphosphine tetrafluoroborate were added to the reaction mixture. After two additional freeze-pump-thaw cycles, the reaction mixture was heated to 94° C. for 14 hours. The reaction mixture was cooled to room temperature and it was filtered through a pad of celite, and washed with toluene. Then the solution was concentrated. The residue was purified by silica-gel column chromatography using cyclohexane as eluent to give 36.1 g (73% yield) of Intermediate 2-1 as an orange oil.
LC-MS: 301.3 [M+1]+
36.1 g (120.18 mmol) of Intermediate 2-1 and 48.21 g (901.36 mmol) of ammonium chloride were suspended in 900 mL of 1,4-dioxane and 300 mL of ethanol. After 58.9 g (901.36 mmol) of zinc powder was added to the suspension at room temperature, and the mixture was refluxed for 14 h. The reaction mixture was filtered through a pad of celite, and washed with ethyl acetate. After the solution was concentrated, the crude product was purified by silica-gel column chromatography using a mixed solvent of heptane and ethyl acetate as eluent to give 29.5 g (86% yield) of Intermediate 2-2 as a beige solid.
LC-MS: 271.3 [M+1]+
4.97 g (18.38 mmol) of Intermediate 2-2, 10.0 g (17.50 mmol) of Intermediate 1-3, and 3.36 g (35.0 mmol) of sodium tert-butoxide were added to 87 mL of toluene. The suspension was degassed using 3 freeze-pump-thaw cycles, and 240 mg (0.26 mmol) of tris(dibenzylideneacetone)dipalladium(0) and 327 mg (0.33 mmol) of BINAP were added to the reaction mixture. After two additional freeze-pump-thaw cycles, the reaction mixture was heated to 80° C. for 17.5 hours. The reaction was cooled to room temperature and diluted with toluene and water. The organic extracts were washed with water and dried over magnesium sulfate. After the filtration, the solution was concentrated. The residue was purified by silica-gel column chromatography using a mixed solvent of toluene and cyclohexane as eluent to give 13.6 g (99% yield) of Intermediate 2-3 as a white foam.
LC-MS: 762.6 [M+1]+
7.00 g (9.20 mmol) of Intermediate 2-3, 3.24 g (10.12 mmol) of 2-iodo-9,9-dimethyl-9H-fluorene, and 1.24 g (12.88 mmol) of sodium tert-butoxide were added to 92 mL of toluene. The suspension was degassed using 3 freeze-pump-thaw cycles, and 84 mg (0.09 mmol) of tris(dibenzylideneacetone)dipalladium(0) and 110 mg (0.37 mmol) of tri-tert-butylphosphonium tertrafluoroborate were added to the reaction mixture. After two additional freeze-pump-thaw cycles, the reaction mixture was heated to 80° C. for 30 min. The reaction was cooled to room temperature and diluted with toluene and water. The organic extracts were washed with water and dried over magnesium sulfate. After the filtration, the solution was concentrated. The residue was purified by silica-gel column chromatography using a mixed solvent of heptane and toluene as eluent to give 8.39 g (89% yield) of Intermediate 2-4 as a white solid.
LC-MS: 955 [M+1]+
5.41 g (5.68 mmol) of Intermediate 2-4 was added to 103 mL of tert-butylbenzene, and the solution was bubbled with argon. 5.97 mL (11.35 mmol) of 1.9 M tert-butyllithium in pentane was added dropwise to the solution at 5° C., and the reaction mixture was stirred at room temperature for 1 h. The reaction mixture was cooled at −65° C., and 1.08 mL (11.35 mmol) of tribromoborane was added, then the reaction mixture was stirred for 25 min after removal of a dry ice-acetone bath. Then, 5.0 mL (28.38 mmol) of N-ethyl-N-isopropylpropan-2-amine was added, and then the mixture was heated to 153° C. After it was stirred for 2 h, the reaction mixture was cooled at room temperature, and quenched with 10% sodium acetate aqueous solution. The mixture was diluted with toluene, and the aqueous layer was extracted with toluene. The organic layer was washed with water and brine, and dried over magnesium sulfate. After the solution was filtered, it was concentrated. The residue was purified by silica-gel column chromatography using a mixed solvent of heptane and dichloromethane as eluent. Then, it was recrystallized from a mixed solvent of dichloromethane and heptane to give 1.17 g (23% yield) of Compound 2 as a yellow powder.
LC-MS: 881.7 [M+1]+
Intermediate 3-1 was synthesized from Intermediate 1-4 and 2-bromo-9,9-diphenyl-9H-fluorene according to the procedure of Intermediate 1-5 (89% yield).
LC-MS: 1066.6 [M+1]+
Compound 3 was synthesized from Intermediate 3-1 according to the procedure of Compound 1 (32% yield).
LC-MS: 997.0 [M+1]+
Intermediate 4-1 was synthesized according to the procedure of Intermediate 2-1, using bis(4-(tert-butyl)phenyl)amine instead of N-(Phenyl-2,3,4,5,6-d5)benzen-2,3,4,5,6-d5-amine (59% yield).
LC-MS: 403.2 [M+1]+
Intermediate 4-2 was synthesized from Intermediate 4-1 according to the procedure of Intermediate 2-2 (96% yield).
LC-MS: 373.6 [M+1]+
Intermediate 4-3 was synthesized from Intermediate 1-3 and Intermediate 4-2 according to the procedure of Intermediate 1-4 (94% yield).
LC-MS: 862.8 [M+1]+
Intermediate 4-4 was synthesized from Intermediate 4-3 and 4-bromo-9,9-dimethyl-9H-fluorene according to the procedure of Intermediate 1-5 (78% yield).
LC-MS: 1054.9 [M+1]+
Compound 4 was prepared from Intermediate 4-4 according to the procedure of Compound 1 (26% yield).
LC-MS: 984.9 [M+1]+
Intermediate 5-1 was synthesized from Intermediate 4-3 and 2-iodo-9,9-dimethyl-9H-fluorene according to the procedure of Intermediate 1-5 (93% yield).
LC-MS: 1055.0 [M+1]+
Compound 5 was prepared from Intermediate 5-1 according to the procedure of Compound 1 (17% yield).
LC-MS: 984.7 [M+1]+
Intermediate 6-1 was synthesized according to the procedure of Intermediate 2-1, using N-[4-(1,1-Dimethylethyl)phenyl][1,1′-biphenyl]-2-amine instead of N-(Phenyl-2,3,4,5,6-d5)benzen2,3,4,5,6-d5-amine. Yield was 65%.
LC-MS: 423.2 [M+1]+
Intermediate 6-2 was synthesized from Intermediate 6-1 according to the procedure of Intermediate 2-2. Yield was 85%.
LC-MS: 393.3 [M+1]+
Intermediate 6-3 was synthesized from Intermediate 6-2 and Intermediate 1-3 according to the procedure of Intermediate 2-3. Yield was 93%.
LC-MS: 884.6 [M+1]+
Intermediate 6-4 was synthesized from Intermediate 6-3 and 2-iodo-9,9-dimethyl-9H-fluorene according to the procedure of Intermediate 2-4. Yield was 91%.
LC-MS: 1076.6 [M+1]+
Compound 6 was synthesized from Intermediate 6-4 according to the procedure of Compound 2. Yield was 19%.
LC-MS: 1004.7 [M+1]+
Intermediate 7-1 was synthesized according to the procedure of Intermediate 2-1, using 5-(tertbutyl)-Mphenyl-[1,1′-biphenyl]-2-amine instead of N-(Phenyl-2,3,4,5,6-d5)benzen-2,3,4,5,E6-damine. Yield was 93%.
LC-MS: 423.3 [M+1]+
Intermediate 7-2 was synthesized from Intermediate 7-1 according to the procedure of Intermediate 2-2. Yield was 98%.
LC-MS: 393.3 [M+1]+
Intermediate 7-3 was synthesized from Intermediate 7-2 and Intermediate 1-3 according to the procedure of Intermediate 2-3. Yield was 88%.
LC-MS: 884.6 [M+1]+
Intermediate 7-4 was synthesized from Intermediate 7-3 and 2-iodo-9,9-dimethyl-9H-fluorene according to the procedure of Intermediate 2-4. Yield was 95%.
LC-MS: 1076.6 [M+1]+
Compound 7 was synthesized from Intermediate 7-4 according to the procedure of Compound 2. Yield was 21%.
LC-MS: 1004.7 [M+1]+
Intermediate 8-1 was synthesized according to the procedure of Intermediate 2-1, using 4-(tertbutyl)-N-(4-(tert-butyl)phenyl)-2,6-dimethylaniline instead of N-(Phenyl-2,3,4,5,6-d5)benzen2,3,4,5,6-d amine. Yield was 85%.
LC-MS: 431.4 [M+1]+
Intermediate 8-1 Intermediate 8-2 Intermediate 8-2 was synthesized from Intermediate 8-1 according to the procedure of Intermediate 2-2. Yield was 94%.
LC-MS: 401.3 [M+1]+
Intermediate 8-3 was synthesized from Intermediate 8-2 and Intermediate 1-3 according to the procedure of Intermediate 2-3. Yield was 84%.
LC-MS: 892.6 [M+1]+
Intermediate 8-3 Intermediate 8-4 Intermediate 8-4 was synthesized from Intermediate 8-3 and 2-iodo-9,9-dimethyl-9H-fluorene according to the procedure of Intermediate 2-4. Yield was 91%.LC-MS: 1084.6 [M+1]+
Intermediate 8-4 Compound 8 Compound 8 was synthesized from Intermediate 8-4 according to the procedure of Compound 2. Yield was 16%.
LC-MS: 1012.8 [M+1]+
Intermediate 9-1 was synthesized according to the procedure of Intermediate 2-1, using di([1,1′-biphenyl]-4-yl)amine instead of N-(Phenyl-2,3,4,5,6-d5)benzen-2,3,4,5,6-d5-amine. Yield was 93%.
LC-MS: 443.3 [M+1]+
Intermediate 9-1 Intermediate 9-2 Intermediate 9-2 was synthesized from Intermediate 9-1 according to the procedure of Intermediate 2-2. Yield was 90%.
LC-MS: 413.4 [M+1]+
Intermediate 9-3 was synthesized from Intermediate 9-2 and Intermediate 1-3 according to the procedure of Intermediate 2-3. Yield was 87%.
LC-MS: 904.5 [M+1]+
Intermediate 9-4 was synthesized from Intermediate 9-3 and 2-iodo-9,9-dimethyl-9H-fluorene according to the procedure of Intermediate 2-4. Yield was 96%.
LC-MS: 1096.6 [M+1]+
Compound 9 was synthesized from Intermediate 9-4 according to the procedure of Compound 2. Yield was 24%.
LC-MS: 1024.7 [M+1]+
Intermediate 10-1 was synthesized according to the procedure of Intermediate 1-1, using 1,2-dibromo-4-methylbenzene instead of 1,2-dibromo-4-(tert-butyl)benzene.
Intermediate 10-2 was synthesized from Intermediate 10-1 according to the procedure of Intermediate 1-2. Yield was 58%.
48.0 g (110 mmol) of 3-Bromo-N,N-bis[4-(1,1-dimethylethyl)phenyl]benzenamine, 16.4 g (110 mmol) of 4-(tert-butyl)aniline, and 26.4 g (275 mmol) of sodium tert-butoxide were added to 450 mL of toluene. The suspension was degassed using 3 freeze-pump-thaw cycles, and 504 mg (0.55 mmol) of tris(dibenzylideneacetone)dipalladium(0) and 685 mg (1.1 mmol) of BINAP were added to the reaction mixture. After two additional freeze-pump-thaw cycles, the reaction mixture was heated to 80° C. for 3 hours. The reaction was cooled to room temperature and diluted with toluene. The organic extracts were washed with water and dried over magnesium sulfate, filtered, and the solution was concentrated. The residue was purified by silica-gel column chromatography using a mixed solvent of heptane and dichloromethane as eluent to give 52.3 g (94% yield) of Intermediate 10-3 as a white foam.
LC-MS: 505.5 [M+1]+
Intermediate 10-4 was synthesized according to the procedure of Intermediate 1-3, using Intermediate 10-2 instead of Intermediate 1-2, and Intermediate 10-3 instead of bis(4-(tert-butyl)phenylamine. Yield was 57%.
LC-MS: 753.4 [M+1]+
Intermediate 10-5 was synthesized from Intermediate 10-4 and 3-(tert-butyl)aniline according to the procedure of Intermediate 2-3. Yield was 89%.
LC-MS: 822.5 [M+1]+
Intermediate 10-6 was synthesized from Intermediate 10-5 and 2-iodo-9,9-dimethyl-9H-fluorene according to the procedure of Intermediate 2-4. Yield was 77%.
LC-MS: 1014.8 [M+1]+
Intermediate 10-6 Compound 10 Compound 10 was synthesized from Intermediate 10-6 according to the procedure of Compound 2. Yield was 30%.
LC-MS: 944.9 [M+1]+
Intermediate 11-1 was synthesized from Intermediate 10-2 and bis(4-(tert-butyl)phenylamine according to the procedure of Intermediate 1-3. Yield was 58%.
LC-MS: 530.2 [M+1]+
Intermediate 11-2 was synthesized from Intermediate 8-2 and Intermediate 11-1 according to the procedure of Intermediate 2-3. Yield was 81%.
LC-MS: 850.6 [M+1]+
Intermediate 11-3 was synthesized from Intermediate 11-2 and 2-iodo-9,9-dimethyl-9H-fluorene according to the procedure of Intermediate 2-4. Yield was 94%.
LC-MS: 1042.4 [M+1]+
Compound 11 was synthesized from Intermediate 11-3 according to the procedure of Compound 2. Yield was 21%.
LC-MS: 970.8 [M+1]+
Intermediate 12-1 was synthesized according to the procedure of Intermediate 2-1, using 4-Methyl-N-(4-methyl[1,1′-biphenyl]-3-yl)[1,1′-biphenyl]-3-amine instead of M(Phenyl-2,3,4,5,6-d5)benzen-2,3,4,5,6-d5-amine. Yield was 93%.
LC-MS: 471.3 [M+1]+
Intermediate 12-2 was synthesized from Intermediate 12-1 according to the procedure of Intermediate 2-2. Yield was 96%.
LC-MS: 441.3 [M+1]+
Intermediate 12-3 was synthesized from Intermediate 12-2 and Intermediate 11-1 according to the procedure of Intermediate 2-3. Yield was 90%.
LC-MS: 880.5 [M+1]+
Intermediate 12-4 was synthesized from Intermediate 12-3 and 2-iodo-9,9-dimethyl-9H-fluorene according to the procedure of Intermediate 2-4. Yield was 87%.
LC-MS: 1082.6 [M+1]+
Compound 12 was synthesized from Intermediate 12-4 according to the procedure of Compound 2. Yield was 17%.
LC-MS: 1010.6 [M+1]+
20.00 g (76 mmol) of methyl 2-iodobenzoate, 14.95 g (84 mmol) of (4-(tertbutyl)phenyl)boronic acid and 24.27 g (229 mmol) of sodium carbonate were added to 270 mL of toluene, 108 mL of water and 270 mL of ethanol. Nitrogen was bubbled into the reaction mixture for 10 minutes and 0.882 g (0.76 mmol) of Tetrakis(triphenylphosphine)palladium(0) were added. The reaction mixture was heated to 80° C. for 15 hours. The reaction was cooled to room temperature and diluted with toluene and water. The organic extracts were washed with water and dried over magnesium sulfate. After the filtration, the solution was concentrated. The residue was purified by silica-gel column chromatography using a mixed solvent of heptane and toluene as eluent to give 15.41 g (75% yield) of Intermediate 13-1 as a white solid. 1H NMR (300 MHz, DMSO-d6) δ 7.76-7.68 (m, 1H), 7.61 (td, 1=7.5, 1.5 Hz, 1H), 7.51-7.40 (m, 4H), 7.27-7.19 (m, 2H), 3.61 (s, 3H), 1.32 (s, 9H).
83.00 mL (133 mmol) of Methyllithium 1.6 molar solution in diethylether were diluted in 180 mL of dry THE and the solution was cooled to 5° C. using an ice water bath. 13.9 g (51.6 mmol) of Intermediate 13-1 was dissolved in 80 mL of dry THF and was added slowly to the Methyllithium solution, so that the reaction temperature remained below 12° C. The reaction was stirred at room temperature for 1 hour and quenched with 40 mL water. The volatiles were removed and the residue was extracted with dichloromethane. The organic phases were combined, dried over magnesium sulfate, filtered and evaporated to give 13.8 g (100% yield) of colourless oil which was used without further purification.
13.8 g (51.6 mmol) Intermediate 13-2 was dissolved in 180 mL acetic acid, 2.5 mL (26.6 mmol) of concentrated HCl aqueous solution was added and the reaction was stirred at 110° C. for 5.5 hours. After evaporating the solvents, the residue was extracted with water and dichloromethane, the organic phases were combined, dried over magnesium sulfate, filtered and concentrated. The residue was purified by silica-gel column chromatography using a mixed solvent of heptane and dichloromethane as eluent to give 10.02 g(73% yield) of intermediate 13-3 as a colourless glass.
1H NMR (300 MHz, DMSO-d5) δ 7.82-7.74 (m, 1H), 7.72 (dd, J=8.0, 0.6 Hz, 1H), 7.60-7.54 (m, 1H), 7.54-7.48 (m, 1H), 7.38 (dd, J=8.0, 1.8 Hz, 1H), 7.35-7.21 (m, 2H), 1.44 (s, 6H), 1.35 (s, 9H).
10.02 g (39.1 mmol) of Intermediate 13-3 were dissolved in 390 mL of dichloromethane and cooled to 5° using an ice water bath. 1.91 mL (37.1 mmol) of bromine were dissolved in 20 mL of dichloromethane, placed in a dropping funnel and added over 10 minutes to the solution of intermediate 13-3 so that the reaction temperature does not exceed 10°. The reaction is stirred at 5° for 1.5 hour and then further 2.5 hours at room temperature. The reaction was quenched with an aqueous solution of sodium thiosulfate, the phases were separated. The aqueous phase was extracted with dichloromethane, the organic phases were combined, washed with water, and brine, dried over magnesium sulfate, filtered and concentrated. The residue was purified by silica-gel column chromatography using a mixed solvent of heptane and toluene as eluent to give 7.90 g (61% yield) of intermediate 13-4 as a white solid.
1H NMR (300 MHz, Chloroform-d) δ 7.63 (dd, J=8.0, 0.7 Hz, 1H), 7.57 (dd, J=6.3, 0.6 Hz, 1H), 7.55 (s, 1H), 7.50-7.43 (m, 2H), 7.41 (dd, J=8.0, 1.8 Hz, 1H), 1.50 (s, 6H), 1.40 (s, 9H).
Intermediate 13-5 was synthesized from Intermediate 13-4 and Intermediate 1-4 according to the procedure of Intermediate 2-4. Yield was 71%.
LC-MS: 998.5 [M+1]+
Compound 13 was synthesized from Intermediate 13-5 according to the procedure of Compound 2. Yield was 14%.
LC-MS: 928.6 [M+1]+
14.08 g (115 mmol) of phenylboronic acid, 21.00 g (105 mmol) of 4-bromo-3,5-dimethylaniline, and 89.00 g (420 mmol) of potassium phosphate tri basic were added to 262 mL of toluene, 175 mL of dioxane and 87 mL of water. The suspension was degassed by bubbling nitrogen for 20 minutes, and 471 mg (2.10 mmol) of palladium(II) acetate and 1.72 g (4.20 mmol) of Dicyclohexyl(2′,6′-dimethoxy[1,1′-biphenyl]-2-yl)phosphane were added to the reaction mixture. which was heated to 80° C. for 1.5 hour. The reaction was cooled to room temperature and diluted with toluene and water. The organic extracts were washed with water and dried over magnesium sulfate, filtered, and the solution was concentrated. The residue was purified by silica-gel column chromatography using a mixed solvent of heptane and ethyl acetate as eluent to give 19.75 g (95% yield) of Intermediate 14-1 as a white solid.
LC-MS: 198.1 [M+1]+
Intermediate 14-2 was synthesized from Intermediate 14-1 and 2,6-dimethyl-4-bromobiphenyl according to the procedure of Intermediate 1-5. Yield was 69%.
LC-MS: 378.2 [M+1]+
Intermediate 14-3 was synthesized from Intermediate 14-2 according to the procedure of Intermediate 2-1. Yield was 65%.
LC-MS: 499.2 [M+1]+
Intermediate 14-3 Intermediate 14-4 Intermediate 14-4 was synthesized from Intermediate 14-3 according to the procedure of Intermediate 2-2. Yield was 88%.
LC-MS: 469.3 [M+1]+
Intermediate 14-5 was synthesized from Intermediate 10-2 and bis(4-(tert-butyl)phenylamine according to the procedure of Intermediate 1-3. Yield was 55%.
LC-MS: 530.1 [M+1]+
Intermediate 14-6 was synthesized from Intermediate 14-5 and Intermediate 14-4 according to the procedure of Intermediate 1-4. Yield was 89%.
LC-MS: 916.4 [M+1]+
Intermediate 14-7 was synthesized from Intermediate 14-5 according to the procedure of Intermediate 1-5. Yield was 91%.
LC-MS: 1108.5 [M+1]+
Compound 14 was synthesized from Intermediate 14-7 according to the procedure of Compound 1. Yield was 28%.
LC-MS: 1038.6 [M+1]+
Intermediate 4-2 Intermediate 15-1 Intermediate 15-1 was synthesized from Intermediate 4-2 and 2-bromo-9,9-dimethyl-9H-fluorene according to the procedure of Intermediate 10-3. Yield was 91%.
LC-MS: 565.4 [M+1]+
Intermediate 15-2 was synthesized from Intermediate 15-1 and Intermediate 10-2 according to the procedure of Intermediate 1-3. Yield was 49%.
LC-MS: 813.2 [M+1]+
Intermediate 15-3 was synthesized from Intermediate 15-2 and 3-tert-butylaniline according to the procedure of Intermediate 1-4. Yield was 87%.
LC-MS: 880.4 [M+1]+
Intermediate 15-4 was synthesized from Intermediate 15-3 and 4-(tert-butyl)-4′-iodo-1,1′-biphenyl according to the procedure of Intermediate 1-5. Yield was 72%.
LC-MS: 1088.5 [M+1]+
Compound 15 was synthesized from Intermediate 15-4 according to the procedure of Compound 1. Yield was 11%.
LC-MS: 1018.6 [M+1]+
Intermediate 16-1 was synthesized from Intermediate 15-3 and 1-tert-butyl-4-iodobenzene according to the procedure of Intermediate 1-5. Yield was 83%.
LC-MS: 1012.5 [M+1]+
Compound 16 was synthesized from Intermediate 16-1 according to the procedure of Compound 1. Yield was 9%.
LC-MS: 942.6 [M+1]+
Intermediate 17-1 was synthesized from Intermediate 1-4 and 4-bromo-9,9-diphenyl-9H-fluorene according to the procedure of Intermediate 1-5. Yield was 25%.
LC-MS: 1067.6 [M+1]+
Compound 17 was synthesized from Intermediate 17-1 according to the procedure of Compound 1. Yield was 37%.
LC-MS: 881.7 [M+1]+
Intermediate 18-1 was synthesized from Intermediate 15-3 and 2-iodo-9,9-dimethyl-9H-fluorene according to the procedure of Intermediate 1-5. Yield was 67%.
LC-MS: 1072.5 [M+1]+
Compound 18 was synthesized from Intermediate 18-1 according to the procedure of Compound 1. Yield was 12%
LC-MS: 942.6 [M+1]+
The organic EL devices were prepared and evaluated as follows:
A glass substrate with 130 nm-thick indium-tin-oxide (ITO) transparent electrode (manufactured by Geomatec Co., Ltd.) used as an anode was first treated with N2 plasma for 100 sec. This treatment also improved the hole injection properties of the ITO. The cleaned substrate was mounted on a substrate holder and loaded into a vacuum chamber. Thereafter, the organic materials specified below were applied by vapour deposition to the ITO substrate at a rate of approx. 0.2-1 Å/sec at about 10−6-10−8 mbar. As a hole injection layer, 10 nm-thick mixture of Compound HT-1 and 3% by weight of compound HI was applied. Then 80 nm-thick of compound HT-1 and 10 nm of Compound HT-2 were applied as hole-transporting layer 1 and hole-transporting layer 2, respectively. Subsequently, a mixture of 2% by weight of an emitter Compound 1 and 98% by weight of host Compound BH-1 was applied to form a 25 nm-thick fluorescent emitting layer. On the emitting layer, 10 nm-thick Compound ET-1 was applied as an hole-blocking layer and 15 nm of Compound ET-2 as electron-transporting layer. Finally, 1 nm-thick LiF was deposited as an electron-injection layer and 80 nm-thick A1 was then deposited as a cathode to complete the device. The device was sealed with a glass lid and a getter in an inert nitrogen atmosphere with less than 1 ppm of water and oxygen. To characterize the OLED, electroluminescence (EL) spectra were recorded at various currents and voltages. EL peak maximum and Full Width at Half Maximum (FWHM) were recorded at 10 mA/cm2. In addition, the current-voltage characteristic were measured in combination with the luminance to determine luminous efficiency and external quantum efficiency (EQE). Driving voltage (Voltage) was given at a current density of 10 mA/cm2. The device results are shown in Table 1.
These results demonstrate that the Application Example 1 give good EQE and narrow spectrum (smaller FWHM), i.e. good colour purity when used as fluorescent emitting material in OLED.
Application example 1 was repeated, except Comparative Compound 1 and Compounds 2-13 and 15-17 were used instead of Compound 1 as emitter in fluorescent emitting layer.
These results demonstrate that the inventive compounds give higher EQE compared to the comparative compound 1 while maintaining narrow spectrum (smaller FWHM), i.e. good colour purity when used as fluorescent emitting material in OLED.
| Number | Date | Country | Kind |
|---|---|---|---|
| 21197537.0 | Sep 2021 | EP | regional |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2022/030206 | 7/29/2022 | WO |
