JP5098177B2 - Organic compounds, charge transport materials, and organic electroluminescent devices - Google Patents

Description

  The present invention relates to a novel organic compound and charge transport material, and an organic electroluminescent device using the organic compound, and more specifically, an organic compound and charge transport material that are stable even after repeated electrical oxidation and reduction. The present invention relates to an organic electroluminescent device using this organic compound and having high luminous efficiency and high driving stability.

  An electroluminescent device using an organic thin film has been developed. An electroluminescent element using an organic thin film, that is, an organic electroluminescent element, usually has an organic layer including an anode, a cathode, and at least a light emitting layer provided between these electrodes on a substrate. In addition to the light emitting layer, a hole injection layer (anode buffer layer), a hole transport layer, a hole blocking layer, an electron transport layer, an electron injection layer, and the like are provided as the organic layer. Usually, an organic electroluminescent element is constituted by laminating these layers between an anode and a cathode.

  Conventionally, organic electroluminescent devices have used fluorescent light emission, but in an attempt to increase the light emission efficiency of the device, it has been studied to use phosphorescent light emission instead of fluorescent light. However, even if phosphorescence is used, the present situation is that sufficient luminous efficiency has not been obtained yet.

しかしながら、上記ビフェニル誘導体を用いた有機電界発光素子は、電荷の再結合位置が陰極側に偏る傾向があり、バランスが取り辛く、高い発光効率が得られていなかった。 Many of organic electroluminescent elements using phosphorescent molecules developed so far are characterized by using a material containing a carbazolyl group as a material (host material) of a light emitting layer. For example, Non-Patent Document 1 Uses the following biphenyl derivatives as host materials.

However, the organic electroluminescent device using the biphenyl derivative has a tendency that the recombination position of charges tends to be biased toward the cathode side, is not well balanced, and high luminous efficiency has not been obtained.

しかしながら、上記化合物は、ピリジン環を１つしか有しておらず、ＬＵＭＯが１つのピリジン環に局在化しているため、電子輸送能が低く、更に、一電子還元されたときの耐久性に問題がある。このため、該化合物は、高電圧下でしか発光が観測されず、発光輝度、発光効率が不十分である。 Therefore, in recent years, a host material having both hole transporting properties and electron transporting properties has been proposed for the purpose of concentrating the recombination region in the light emitting layer. Patent Document 1 discloses a compound shown below in an organic electroluminescent device. The use is described.

However, since the above compound has only one pyridine ring and LUMO is localized in one pyridine ring, the electron transport ability is low, and the durability when reduced by one electron is further improved. There's a problem. For this reason, the compound emits light only under a high voltage, and the light emission luminance and light emission efficiency are insufficient.

しかしながら、これらの化合物は、ピリジン環又はピラジン環を１つしか有しておらず、前述したように、電子輸送能及び一電子還元されたときの耐久性の点で改善の必要がある。更に、窒素原子を同一の環に２つ以上含むピラジン環やピリミジン環などを有する化合物は、ピリジン環を有する化合物に比べて、三重項励起準位が低く、一電子還元されたときの耐久性も低いと考えられるため、ホスト材料としては問題がある。 Patent Document 2 proposes the use of the following compounds as materials for organic electroluminescent elements.

However, these compounds have only one pyridine ring or pyrazine ring, and as described above, there is a need for improvement in terms of electron transport ability and durability when reduced by one electron. Furthermore, a compound having a pyrazine ring or a pyrimidine ring containing two or more nitrogen atoms in the same ring has a lower triplet excitation level than a compound having a pyridine ring, and durability when reduced by one electron. Therefore, there is a problem as a host material.

これらの化合物は、直接結合された２つのピリジン環（ビピリジル骨格）を有するため、ある程度ＬＵＭＯが非局在化し、電子輸送能が若干改善されていると考えられる。しかしながら、これらの化合物のピリジン環は、もう一方のピリジン環と直接結合している炭素原子の、両側のオルト位の炭素原子が、全て水素原子又は置換基に結合している。このため、立体障害により、これらの化合物のピビリジル骨格は平面性に乏しく、ＬＵＭＯの非局在化が未だ不十分であり、電子輸送能に問題がある。更に、ビピリジル骨格は一電子還元されたときに平面性が高くなるため、ビピリジル骨格の平面性が高くなりにくいこれらの化合物は、一電子還元されたときの耐久性に問題があり、実用的な駆動寿命を達成し得ない。 Patent Document 2 and Patent Document 3 propose using the following compounds as materials for organic electroluminescent elements.

Since these compounds have two pyridine rings (bipyridyl skeleton) directly bonded, it is considered that LUMO is delocalized to some extent and the electron transport ability is slightly improved. However, in the pyridine ring of these compounds, all the carbon atoms in the ortho positions on both sides of the carbon atom directly bonded to the other pyridine ring are bonded to a hydrogen atom or a substituent. For this reason, due to steric hindrance, these compounds have poor planarity, LUMO delocalization is still insufficient, and there is a problem in electron transport ability. Further, since the bipyridyl skeleton has a high planarity when it is reduced by one electron, these compounds, which are difficult to increase the flatness of the bipyridyl skeleton, have a problem in durability when reduced by one electron, and are practical. The drive life cannot be achieved.

これらの化合物は、電子輸送能及び一電子還元されたときの耐久性は改善されていることが予想されるものの、カルバゾリル基が一つだけであるため、正孔輸送性に乏しく、有機電界発光素子の発光層の材料としては、正孔輸送性と電子輸送性のバランスが悪く、ホスト材料としては改善が必要である。
特開平６−１９７２号公報 国際公開第ＷＯ０３／０７８５４１号パンフレット 特開２００４−２７３１９０号公報 国際公開第ＷＯ０３／０８０７６０号パンフレット Appl.Phys.Lett.,75巻，4頁，1999年 Patent Document 2 and Patent Document 4 propose using the following compounds as materials for organic electroluminescent elements.

Although these compounds are expected to have improved electron transport ability and durability when reduced by one electron, since they have only one carbazolyl group, they have poor hole transportability and organic electroluminescence. As the material of the light emitting layer of the element, the balance between the hole transport property and the electron transport property is poor, and the host material needs to be improved.
JP-A-6-1972 International Publication No. WO03 / 078541 Pamphlet JP 2004-273190 A International Publication No. WO03 / 080760 Pamphlet Appl. Phys. Lett., 75, 4, pp. 1999

  The present invention has an excellent hole transporting property and electron transporting property, and has an excellent electrical redox durability and a high triplet excited level, an organic compound and a charge transporting material, and a high It is an object of the present invention to provide an organic electroluminescence device having luminous efficiency and high driving stability.

  As a result of intensive studies, the present inventors have found that an organic compound having the following structure has excellent hole transportability and electron transportability, and has excellent electrical redox durability and high triplet excitation level. The present inventors have found that when used in an organic electroluminescence device, they exhibit high luminous efficiency and high driving stability, and have reached the present invention.

（式中、Ｃｚ^１及びＣｚ^２は、カルバゾリル基を表す。Ｃｚ^１及びＣｚ^２は同一であっても異なっていても良い。
Ｑ^１及びＱ^２は、直接結合又は下記（１）から選ばれる連結基を表す。Ｑ^１及びＱ^２は同一であっても異なっていても良い。
Ｃｚ^１、Ｃｚ^２、Ｑ^１、Ｑ^２、環Ｂ^１及び環Ｂ^２は、それぞれ下記（２）から選ばれる置換基を有していても良い。）
（１） ベンゼン環、ナフタレン環、アントラセン環、フェナントレン環、ペリレン環、テトラセン環、ピレン環、ベンズピレン環、クリセン環、トリフェニレン環、フルオランテン環の、６員環の単環又は２〜５縮合環由来の２価の連結基、或いは、それらが複数個連結されて形成された２価の連結基
（２） アルキル基、芳香族炭化水素基、アシル基、アルコキシ基、アリールオキシ基、アルキルチオ基、アリールチオ基、アルコキシカルボニル基、アリールオキシカルボニル基、ハロゲン原子、アリールアミノ基、アルキルアミノ基、芳香族複素環基

（式中、環Ｂ ^１ 及び環Ｂ ^２ は、式（Ｉ）におけると同義である。） That is, the gist of the present invention is an organic compound represented by the following formula (I), wherein the following formula (I ′), which is a partial structure of the following formula (I), is represented by the following formula (III-1): An organic compound (claim 1).
Another subject matter of the present invention resides in a charge transporting material (claim 6 ) characterized by containing this organic compound.
Still another subject matter of the present invention is an organic electroluminescent device having an anode, a cathode, and an organic light emitting layer provided between both electrodes on a substrate, and the organic compound is contained between the anode and the cathode. The present invention resides in an organic electroluminescent element having a layer formed as described above (claim 7 ).

(In the formula, Cz ¹ and Cz ² represent a carbazolyl group. Cz ¹ and Cz ² may be the same or different.
Q ¹ and Q ² represent a direct bond or a linking group selected from the following (1). Q ¹ and Q ² may be the same or different.
Cz ¹ , Cz ² , Q ¹ , Q ² , Ring B ¹ and Ring B ² may each have a substituent selected from the following (2). )
(1) Benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, perylene ring, tetracene ring, pyrene ring, benzpyrene ring, chrysene ring, triphenylene ring, fluoranthene ring, 6-membered monocyclic ring or 2-5 condensed ring Or a divalent linking group formed by linking a plurality of them (2) alkyl group, aromatic hydrocarbon group, acyl group, alkoxy group, aryloxy group, alkylthio group, arylthio group Group, alkoxycarbonyl group, aryloxycarbonyl group, halogen atom, arylamino group, alkylamino group, aromatic heterocyclic group

(In the formula, ring B ¹ and ring B ² have the same meanings as in formula (I).)

（式中、Ｇ^１〜Ｇ^４は、直接結合又は下記（１）から選ばれる連結基を表す。Ｇ^１〜Ｇ^４はそれぞれ同一であっても異なっていても良い。
環Ａ^１及び環Ａ^２は、それぞれ下記（２）から選ばれる置換基を有していても良いベンゼン環である。
Ｃｚ^１、Ｃｚ^２、環Ｂ^１及び環Ｂ^２は、式（Ｉ）におけると同義である。）

（式中、Ｇ^５は、直接結合又は下記（１）から選ばれる連結基を表す。
Ｚは、Ｃｚ^１及びＣｚ^２上の窒素原子同士を共役可能とする下記（１）から選ばれる連結基を表す。Ｚは下記（２）から選ばれる置換基を有していても良い。
Ｃｚ^１、Ｃｚ^２、環Ｂ^１及び環Ｂ^２は、式（Ｉ）におけると同義である。）
（１） ベンゼン環、ナフタレン環、アントラセン環、フェナントレン環、ペリレン環、テトラセン環、ピレン環、ベンズピレン環、クリセン環、トリフェニレン環、フルオランテン環の、６員環の単環又は２〜５縮合環由来の２価の連結基、或いは、それらが複数個連結されて形成された２価の連結基
（２） アルキル基、芳香族炭化水素基、アシル基、アルコキシ基、アリールオキシ基、アルキルチオ基、アリールチオ基、アルコキシカルボニル基、アリールオキシカルボニル基、ハロゲン原子、アリールアミノ基、アルキルアミノ基、芳香族複素環基

（式中、Ｃｚ^１、Ｃｚ^２、Ｑ^１、Ｑ^２、環Ｂ^１及び環Ｂ^２は、式（Ｉ）におけると同義である。）

（式中、Ｃｚ^１、Ｃｚ^２、Ｑ^１、Ｑ^２、環Ｂ^１及び環Ｂ^２は、式（Ｉ）におけると同義である。） In the present invention, the formula (I) is preferably any of the following formulas (I-1) to (I-3) (claims 2 to 4).

(In the formula, G ^{1 to} G ⁴ represent a direct bond or a linking group selected from the following (1). G ^{1 to} G ⁴ may be the same or different.
Ring A ¹ and ring A ² are each a benzene ring which may have a substituent selected from the following (2) .
Cz ¹ , Cz ² , ring B ¹ and ring B ² are as defined in formula (I). )

(In the formula, G ⁵ represents a direct bond or a linking group selected from the following (1) .
Z represents a linking group selected from the following (1) capable of conjugating nitrogen atoms on Cz ¹ and Cz ² . Z may have a substituent selected from the following (2) .
Cz ¹ , Cz ² , ring B ¹ and ring B ² are as defined in formula (I). )
(1) Benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, perylene ring, tetracene ring, pyrene ring, benzpyrene ring, chrysene ring, triphenylene ring, fluoranthene ring, 6-membered monocyclic ring or 2-5 condensed ring Or a divalent linking group formed by linking a plurality of them.
(2) alkyl group, aromatic hydrocarbon group, acyl group, alkoxy group, aryloxy group, alkylthio group, arylthio group, alkoxycarbonyl group, aryloxycarbonyl group, halogen atom, arylamino group, alkylamino group, aromatic Heterocyclic group

(In the formula, Cz ¹ , Cz ² , Q ¹ , Q ² , ring B ¹ and ring B ² have the same meanings as in formula (I).)

(In the formula, Cz ¹ , Cz ² , Q ¹ , Q ² , ring B ¹ and ring B ² have the same meanings as in formula (I).)

Moreover, it is preferable that all the carbazolyl groups which exist in the molecule | numerator of the organic compound of this invention are N-carbazolyl groups represented by following formula (II) (Claim 5 ).

  The organic compound of the present invention has a high triplet excitation order, excellent charge transportability (hole transportability, electron transportability), and electrical redox durability. For this reason, according to the organic electroluminescent element using this organic compound, it is possible to emit light with high luminance and high efficiency, and the stability of the element, particularly the driving stability, is improved and the life is extended.

  The organic electroluminescent element using the organic compound of the present invention is a light source (for example, a copy) that takes advantage of the characteristics of a flat panel display (for example, for an OA computer or a wall-mounted television), an in-vehicle display element, a mobile phone display or a surface light emitter. It can be applied to machine light sources, back light sources for liquid crystal displays and instruments, display panels, and sign lamps, and its technical value is great.

In addition, since the organic compound of the present invention has essentially excellent redox stability, it is useful not only for organic electroluminescence devices but also for electrophotographic photoreceptors.
The organic compound of the present invention is not only used for charge transport materials, but also for various light emitting materials, for solar cell materials, for battery materials (electrolytes, electrodes, separation membranes, stabilizers, etc.), medical use, and paint materials. It is also useful for coating materials, coating materials, organic semiconductor materials, toiletry materials, antistatic materials, thermoelectric element materials, and the like.

  In addition, the charge transport material of the present invention has a hole injection material, a hole transport material, a light emitting material, and a host material in accordance with the layer structure of the element because of excellent film forming properties, charge transport properties, light emitting characteristics, and heat resistance. It can also be applied as an electron injection material, an electron transport material, and the like.

  Embodiments of an organic compound, a charge transport material, and an organic electroluminescent element of the present invention will be described in detail below, but the description of the constituent elements described below is an example (representative example) of an embodiment of the present invention. The present invention is not limited to these contents unless it exceeds the gist.

（式中、Ｃｚ^１及びＣｚ^２は、カルバゾリル基を表す。Ｃｚ^１及びＣｚ^２は同一であっても異なっていても良い。
Ｑ^１及びＱ^２は、直接結合又は任意の連結基を表す。Ｑ^１及びＱ^２は同一であっても異なっていても良い。
Ｃｚ^１、Ｃｚ^２、Ｑ^１、Ｑ^２、環Ｂ^１及び環Ｂ^２は、それぞれ置換基を有していても良い。） [Organic compounds]
The organic compound of the present invention is represented by the following formula (I).

(In the formula, Cz ¹ and Cz ² represent a carbazolyl group. Cz ¹ and Cz ² may be the same or different.
Q ¹ and Q ² represent a direct bond or an arbitrary linking group. Q ¹ and Q ² may be the same or different.
Cz ¹ , Cz ² , Q ¹ , Q ² , ring B ¹ and ring B ² may each have a substituent. )

[1] Structural features The organic compound of the present invention represented by the above formula (I) has excellent oxidation-reduction durability, and a part mainly responsible for electron transport and a part mainly responsible for hole transport. It is characterized by being well-balanced.

Ring B ¹ is mainly responsible moiety an electron-transporting organic compound in the present invention - Ring B ² is a hydrogen atom or a substituent group at the N-atom of the ring B ² is not attached, the ring B ^1, ring B ² Since the steric hindrance between them is small, a bipyridyl skeleton with high planarity is formed. For this reason, since LUMO is sufficiently delocalized on ring B ¹ -ring B ^2, it has excellent electron transport ability, and furthermore, there is a structural change between the ground state and the one-electron reduced state. Since it is small, it has excellent durability when it is reduced by one electron.

  Since the organic compound of the present invention has such characteristics, the element driving voltage when an organic electroluminescent element is formed is reduced, and the element driving stability is further improved.

Moreover, since the organic compound of the present invention has two or more carbazolyl groups such as Cz ¹ -Q ¹ -and Cz ² -Q ^2- as a part mainly responsible for hole transport, it has excellent hole transport ability. Therefore, the device driving voltage when an organic electroluminescent device is formed is reduced, and it becomes easy to balance supply of positive and negative charges necessary for causing recombination of holes and electrons in the light emitting layer.

[2] The components in the formula (I) <rings ^{B 1} and ring ^B 2>
Ring B ¹ and Ring B ² are pyridine rings, and may have any substituent other than Cz ¹ -Q ¹ -or Cz ² -Q ^2- independently of each other (note that ring B ² is necessarily ^Cz 2 -Q ² - are not intended to be substituted).

The following formula (I ′), which is a partial structure of formula (I), includes the following formula (III-1), (III-2), or (III-3), and among these, LUMO is non- Formula (III-1) and formula (III-2) are preferable from the viewpoint of localization, and formula (III-1) is more preferable because of high flatness and excellent electron transport ability and reduction durability. .

Examples of the substituent that the ring B ¹ and / or the ring B ² may have include, for example, an alkyl group, an aromatic hydrocarbon group, an acyl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, and an alkoxycarbonyl group. , Aryloxycarbonyl group, halogen atom, arylamino group, alkylamino group, aromatic heterocyclic group and the like, preferably alkyl group, aromatic hydrocarbon group, aromatic heterocyclic group, more preferably benzene ring , Naphthalene ring, anthracene ring, phenanthrene ring, perylene ring, tetracene ring, pyrene ring, benzpyrene ring, chrysene ring, triphenylene ring, fluoranthene ring, carbazole ring, etc. A monovalent group or a monovalent group formed by linking a plurality of them (for example, a biphenyl group) A terphenyl, phenyl group), more preferably a phenyl group, a 4-biphenyl group, 3-carbazolylphenyl group, 4-carbazolylphenyl group, an N- carbazolyl group.

When ring B ¹ and / or ring B ² has a substituent, it is preferable to have a substituent at the meta or para position of the carbon atom directly bonded to the other pyridine ring. For example, when ring B ² has a substituent, the ring B ² preferably has a substituent at any of the 4-position, 5-position, and 6-position.

That is, ring B ¹ and ring B ² can be substituted with a maximum of 5 substituents including Cz ¹ -Q ¹ -and Cz ² -Q ^2- , respectively, but directly with the other pyridine ring. When there is a substituent at the ortho position of the bonded carbon atom, the steric hindrance is larger and the electron transporting ability and reduction durability are lower than when there is no substituent (having a hydrogen atom). It is preferable that B ¹ and ring B ² have no substituent at the ortho position of the carbon atom directly bonded to the other pyridine ring.

However, ring B ¹ and ring B ² have no substituent other than Cz ¹ -Q ¹ -and Cz ² -Q ^2- , or ring B ¹ and / or ring B ² are phenyl groups, 3 -It preferably has a carbazolylphenyl group as a substituent, and most preferably, ring B ¹ and ring B ² have no substituent other than Cz ¹ -Q ¹ -and Cz ² -Q ^2-. is there.

That is, in the ring ^{B 1} and / or ring ^{B 2, Cz 1} -Q 1 - case of having a substituent other than, ^{Cz 1} -Q 1 - - and ^Cz 2 -Q ² and ^Cz 2 -Q ² - only only substituted Compared to the case without a group, when one electron is reduced, the negative charge is shielded and the electron transport ability is lowered, so that Cz ¹ -Q ¹ -and Cz are added to ring B ¹ and / or ring B ^{2. 2} -Q ² - that no substituent in addition to, in particular, rings ^{B 1} and ring ^{B 2} is ^Cz 1 -Q ¹ - preferably has no substituent other than - and ^Cz 2 -Q ^2.

<Cz ¹ and Cz ² >
Cz ¹ and Cz ² each represent a carbazolyl group.
Cz ¹ and Cz ² may be the same or different.
Examples of Cz ¹ and Cz ² include an N-carbazolyl group, 1-carbazolyl group, 2-carbazolyl group, 3-carbazolyl group, and 4-carbazolyl group. From the viewpoint of a high triplet excited level and excellent electrochemical stability, an N-carbazolyl group or 2-carbazolyl group is preferable, and an N-carbazolyl group is most preferable.

Formula (I) in the case where Cz ¹ and Cz ² in Formula (I) are N-carbazolyl groups is shown in Formula (I-4) below.

Cz ¹ and Cz ² may each independently have an arbitrary substituent.
The substituent is preferably an alkyl group, aromatic hydrocarbon group, acyl group, alkoxy group, aryloxy group, alkylthio group, arylthio group, alkoxycarbonyl group, aryloxycarbonyl group, halogen atom, arylamino group, alkylamino. Group, an aromatic heterocyclic group, more preferably an alkyl group, an aromatic hydrocarbon group, or an aromatic heterocyclic group.

  From the viewpoint of a high triplet excited level and a viewpoint of avoiding a decrease in electrical resistance due to a bias in charge distribution, this substituent is preferably a benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, perylene ring, tetracene ring. , A pyrene ring, a benzpyrene ring, a chrysene ring, a triphenylene ring, a fluoranthene ring or the like, a monovalent group derived from a 6-membered monocyclic ring or a 2-5 condensed ring, or a plurality of these 1 linked groups A valent group (for example, biphenylenyl group, terphenylenyl group, etc.).

Each of the substituents of Cz ¹ and Cz ² has a total molecular weight of preferably 500 or less, and more preferably 250 or less. Most preferably Cz ¹ and Cz ² are unsubstituted.

In the organic compound of the present invention, all carbazolyl groups present in the molecule are preferably N-carbazolyl groups represented by the following formula (II).

^{<Q 1} and ^Q 2>
Q ¹ and Q ² represent a direct bond or an arbitrary linking group.
Q ¹ and Q ² may be the same or different.

As an arbitrary linking group, a benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, perylene ring, tetracene ring, pyrene ring, benzpyrene ring, chrysene ring, triphenylene ring, fluoranthene ring, etc. Preferred are divalent linking groups derived from ˜5 condensed rings, or divalent linking groups formed by linking a plurality of them (for example, biphenylene group, terphenylene group, etc.). Q ¹ and Q ² are preferably a direct bond or a divalent linking group formed by linking 1 to 8 benzene rings such as a phenylene group, a biphenylene group, or a terphenylene group.

When Q ¹ and Q ² are arbitrary linking groups, Q ¹ and Q ² may each independently have an arbitrary substituent, and the substituent is preferably an alkyl group, aromatic Hydrocarbon group, acyl group, alkoxy group, aryloxy group, alkylthio group, arylthio group, alkoxycarbonyl group, aryloxycarbonyl group, halogen atom, arylamino group, alkylamino group, aromatic heterocyclic group, more preferably Is an alkyl group, an aromatic hydrocarbon group, or an aromatic heterocyclic group, and particularly preferably a benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, perylene ring, tetracene ring, pyrene ring, benzpyrene ring, chrysene ring, triphenylene A monovalent group derived from a 6-membered monocyclic ring or a 2-5 condensed ring, such as a ring or a fluoranthene ring, or a combination thereof. It is a monovalent group (for example, biphenylenyl group, terphenylenyl group, etc.) formed by connecting several.

Q ¹ and Q ² each preferably have a molecular weight of 1000 or less, and more preferably 500 or less.

Q ¹ and Q ² are particularly preferably each a direct bond or — (Ph) _p —. Here, Ph represents a phenylene group which may have a substituent. Moreover, p represents the integer of 1-8, Preferably it is an integer of 1-3. Examples of the substituent for the phenylene group are the same as those exemplified as the substituent for Q ¹ and Q ² above.
In the formula (I), Q ² may be connected to any of ring B ¹ , ring B ² , Q ¹ and Cz ¹ .

<Cz ¹ -Q ¹ -and Cz ² -Q ^2- >
Although Cz ¹ , Cz ² , Q ¹ and Q ² have been described above, preferred combinations of Cz ¹ and Q ¹ and Cz ² and Q ² will be described below.
Preferable embodiments of Cz ¹ -Q ¹ -and Cz ² -Q ^2- include the following [1] to [3].

（式中、Ｃｚは、Ｃｚ^１或いはＣｚ^２を表す。
環Ａは、ベンゼン環を表す。環Ａは置換基を有していても良い。
Ｇ及びＧ’は、それぞれ直接結合或いは任意の連結基を表す。Ｇ及びＧ’は同一であっても異なっていても良い。Ｇ及びＧ’は置換基を有していても良い。 [1] It is preferable that Cz ¹ -Q ¹ -and Cz ² -Q ² -are each represented by the following formula (IV-1). Hereinafter, ^{Cz 1} -Q 1 - and ^Cz 2 -Q ² - are collectively, Cz-Q-called.

(In the formula, Cz represents Cz ¹ or Cz ² .
Ring A represents a benzene ring. Ring A may have a substituent.
G and G ′ each represent a direct bond or an arbitrary linking group. G and G ′ may be the same or different. G and G ′ may have a substituent.

That Cz-Q- is represented by the formula (IV-1), that is, a part mainly responsible for hole transport (carbazolyl group) and a part mainly responsible for electron transport (bipyridyl skeleton) are in a meta position via a benzene ring. By combining, the excellent heat resistance of the benzene ring, excellent electrochemical stability, high triplet excitation level, excellent electrochemical stability, excellent heat resistance, which are the characteristics of the organic compound of the present invention The high triplet excited level is not impaired, and the m-linked benzene ring has both electron accepting properties and electron donating properties. Therefore, it is necessary when the carbazolyl group is oxidized. Accordingly, the organic compound of the present invention has a mechanism of accepting a part of the positive charge and accepting a part of the negative charge as necessary when the rings B ¹ and B ² are reduced. Further improved redox durability The effect is achieved that that.

G and G ′ in the formula (IV-1) are a part of Q in the formula (I). Preferred examples and examples of the substituents that may be included are the same as those described above for Q ¹ and Q ² in the formula (I). It is the same as what I did.

Ring A in formula (IV-1) is a part of Q ¹ and Q ² in formula (I), and examples of substituents that may be included are those described above for Q ¹ and Q ² in formula (I). It is the same as that.

  The molecular weight of the partial structure represented by the formula (IV-1) is preferably 2000 or less, more preferably 1000 or less.

（式中、Ｇ^１〜Ｇ^４は、式(IV−１)のＧ或いはＧ’と同義であり、直接結合又は任意の連結基を表す。Ｇ^１〜Ｇ^４はそれぞれ同一であっても異なっていても良い。
環Ａ^１及び環Ａ^２は、式(IV−１)の環Ａと同義であり、ベンゼン環を表す。環Ａ^１及び環Ａ^２は、それぞれ置換基を有していても良い。
Ｃｚ^１、Ｃｚ^２、環Ｂ^１及び環Ｂ^２は、式（Ｉ）におけると同義である。） Cz ¹ -Q ¹ - and ^Cz 2 -Q ² - If is represented by the formula (IV-1), an organic compound of the present invention is preferably the following formula (I-1).

^(Wherein, G 1 ~G ⁴ has the same meaning as G or G 'of the formula (IV-1), different even in ^.G 1 ~G ⁴ representing a direct bond or any linking group are respectively the same May be.
Ring A ¹ and ring A ² have the same meaning as ring A in formula (IV-1) and represent a benzene ring. Ring A ¹ and ring A ² may each have a substituent.
Cz ¹ , Cz ² , ring B ¹ and ring B ² are as defined in formula (I). )

（式中、Ｃｚ^１及びＣｚ^２は、式（Ｉ）におけると同義である。
Ｇ^５は、直接結合又は任意の連結基を表す。
Ｚは、Ｃｚ^１及びＣｚ^２上の窒素原子同士を共役可能とする任意の連結基を表す。
Ｇ^５及びＺは、それぞれ置換基を有していても良い。） [2] It is preferable that Cz ¹ -Q ¹ -and Cz ² -Q ² -are bonded to form a partial structure represented by the following formula (IV-2).

(In the formula, Cz ¹ and Cz ² are as defined in formula (I).
G ⁵ represents a direct bond or an arbitrary linking group.
Z represents an optional linking group that allows conjugation of nitrogen atoms to each other on Cz ¹ and Cz ^2.
G ⁵ and Z may each have a substituent. )

Cz ¹ and Cz ² are represented by the above formula (IV-2), that is, it is important that nitrogen atoms on two carbazolyl groups can be conjugated via a linking group Z.

  That is, when a plurality of carbazolyl groups are connected to the same aromatic hydrocarbon group (including those having a plurality of rings connected to this aromatic hydrocarbon group (for example, a biphenyl group)), If the nitrogen atoms of the N atom are non-conjugated, excessive positive charges are concentrated on the aromatic hydrocarbon group when subjected to electrical oxidation, or the N, 1,3,6,8- of the carbazolyl group This is not preferable because the localization of the positive charge at at least one of the positions increases and the durability against the electric oxidation is remarkably lowered.

  On the other hand, when two carbazolyl groups are connected on the same aromatic hydrocarbon group (this aromatic hydrocarbon group includes a group in which a plurality of rings are connected (for example, a biphenyl group)), It is preferable that the nitrogen atoms can be conjugated with each other because positive charges are relatively evenly distributed on the aromatic hydrocarbon group and the two carbazolyl groups and are excellent in durability when subjected to one-electron oxidation.

（cis-，trans-のいずれでも可）又はこれらを組み合わせてなる部分構造で連結されていることと同義（ただし、Ｇ^ａ，Ｇ^ｂ，Ｇ^ｃは各々独立に、水素原子又は任意の置換基を表すか、或いは、芳香族炭化水素環や芳香族複素環の一部を構成する。）である。 Here, nitrogen atoms can be conjugated to each other,

(Any of cis- and trans- can be used) or synonymous with being connected by a partial structure formed by combining these (wherein G ^a , G ^b and G ^c are each independently a hydrogen atom or an arbitrary substituent) Or constitutes part of an aromatic hydrocarbon ring or aromatic heterocyclic ring.

On the linking group Z, including Cz ¹ and Cz ² , the total number is preferably ² to 5, more preferably 2 or 4, and most preferably 2.

Since Z in formula (IV-1) is a part of Q ¹ and Q ² in formula (I), specific examples and examples of substituents that may be included are Q ¹ and Q ² in formula (I). Is the same as described above. However, Z is any linking group that allows conjugation of nitrogen atoms to each other on Cz ¹ and Cz ^2.

  Examples of the partial structural formula (IV-2) including Z include the following.

  Among the above examples, V-1, 2, 4-15, 17-21, 27, 28 are more preferable, V-1, 6-9, 11-15 are more preferable, and V-1 is most preferable.

G ⁵ in formula (IV-2) is a part of Q ¹ and Q ² in formula (I). Preferred examples and examples of substituents that may be included are Q ¹ and Q ² in formula (I). Is the same as described above.

  The molecular weight of the partial structure represented by the formula (IV-2) is preferably 3000 or less, and more preferably 1500 or less.

（Ｇ^５は、上記式（IV−２）のＧ^５と同義であり、直接結合又は任意の連結基を表す。
Ｚは、上記式（IV−２）のＺと同義であり、Ｃｚ^１及びＣｚ^２上の窒素原子同士を共役可能とする任意の連結基を表す。Ｚは置換基を有していても良い。
Ｃｚ^１、Ｃｚ^２、Ｑ^１、環Ｂ^１及び環Ｂ^２は、式（Ｉ）におけると同義である。） Cz ¹ -Q ¹ - and ^Cz 2 -Q ² - If is represented by (IV-2), organic compounds of the present invention is preferably represented by the following formula (I-2).

(G ⁵ has the same meaning as G ⁵ of the formula (IV-2), represents a direct bond or any linking group.
Z is synonymous with Z in the above formula (IV-2), and represents an arbitrary linking group that enables conjugation of nitrogen atoms on Cz ¹ and Cz ^{2 to} each other. Z may have a substituent.
Cz ¹ , Cz ² , Q ¹ , ring B ¹ and ring B ² are as defined in formula (I). )

[3] It is preferable that Cz ¹ -Q ¹ -and Cz ² -Q ² -are directly bonded to rings B ¹ and B ² , respectively.
In this case, since the organic compound of the present invention is represented by the following formula (I-3), when one-electron oxidation is performed, the positive charge is more widely distributed, and thus has an excellent hole transport ability. The bipyridyl skeleton is preferable because it is easy to balance the excellent electron transport ability.

(In the formula, Cz ¹ , Cz ² , Q ¹ , Q ² , ring B ¹ and ring B ² have the same meanings as in formula (I).)

[3] Molecular Weight The molecular weight of the organic compound of the present invention is usually 4000 or less, preferably 3000 or less, more preferably 2000 or less, and usually 200 or more, preferably 300 or more, more preferably 400 or more.
When the molecular weight of the organic compound of the present invention exceeds this upper limit, the sublimation property is remarkably lowered, which may cause trouble in the case of using an evaporation method when producing an electroluminescent device, or purification by increasing the molecular weight of impurities. If the lower limit is not reached, the glass transition temperature, the melting point, the vaporization temperature, and the like are lowered, and the heat resistance may be significantly impaired.

[4] Physical Properties The organic compound of the present invention usually has a glass transition temperature of 50 ° C. or higher, but when used in an organic electroluminescent device, the glass transition temperature is 90 ° C. or higher from the viewpoint of heat resistance. The temperature is preferably 110 ° C. or higher. The upper limit of the glass transition temperature is usually about 400 ° C.
The organic compound of the present invention usually has a vaporization temperature of 800 ° C. or lower under normal pressure. However, when used in an organic electroluminescent device, the vaporization temperature is 700 ° C. or lower from the viewpoint of the stability of the vapor deposition process. It is preferable that it is 600 degreeC or less. The lower limit of the vaporization temperature is usually about 300 ° C.
The organic compound of the present invention usually has a melting point of 100 ° C. or higher, but when used in an organic electroluminescent device, the melting point is preferably 150 ° C. or higher, preferably 200 ° C. or higher, from the viewpoint of heat resistance. More preferably it is. The upper limit of the melting point is usually about 500 ° C.

[5] Specific Examples Specific examples preferable as the organic compound of the present invention are shown below, but the present invention is not limited thereto. In the following exemplary structural formulas, —N—Cz represents an N-carbazolyl group.

[6] Synthesis Method The organic compound of the present invention can be synthesized using a known method by selecting raw materials according to the structure of the target compound.

(1) First, as a method for introducing two directly bonded pyridine rings (bipyridyl skeleton), the following methods A) to E) can be employed.

A) Synthesis, 1-24; 1976 and references cited therein, aldehydes and pyridyl acetylides, alone or mixed solvents such as aromatic solvents such as acetic acid, alcohol and nitrobenzene in the presence of a strong acid such as sulfuric acid In an alcohol and / or water solvent in the presence of a strong base such as sodium hydroxide to give an intermediate (-CH = CR-CO-), which is acetic acid, A method of synthesizing an acylpyridinium salt and ammonium acetate in a solvent such as methanol in the presence of oxygen under heating conditions.

B) Synthesis, 1-24; 1976 and references cited therein, Journal of the American Chemical Society, 126, 4958-4971; 2004, Inorganic Chemistry, 42, 2908-2918; 2003, European Journal of Inorganic Chemistry, 1019-1029; The aldehyde and acetylide disclosed in 2001 and the like are reacted in the presence of a strong acid such as sulfuric acid in an aromatic solvent such as acetic acid, alcohol and nitrobenzene alone or in a mixed solvent, or a strong such as sodium hydroxide. Reaction under heating conditions in an alcohol and / or water solvent in the presence of a base gives an intermediate (-CH = CR-CO-), which is heated in a solvent such as acetic acid or methanol under heating conditions in the presence of oxygen. , A method of synthesizing by reacting pyridasylpyridinium salt and ammonium acetate.

C) Synthesis of aldehydes and 1,2-diketones, such as those disclosed in Synthesis, 1-24; 1976 and references cited therein, Inorganic Chemistry, 42, 367-378; 2002, Polyhedron, 22, 93-108; 2003, etc. Reaction in the presence of a strong acid such as acetic acid, alcohol, aromatic solvent such as nitrobenzene alone or in a mixed solvent, or in the presence of a strong base such as sodium hydroxide in an alcohol and / or water solvent under heating conditions A reaction to obtain an intermediate (—CH═CR—CO—) 2, which is synthesized by reacting an acylpyridinium salt and ammonium acetate in a solvent such as acetic acid and methanol under heating in the presence of oxygen. .

D) A halogenated pyridine disclosed in Journal of Organic Chemistry, 67,443-449; 2002, Inorganic Chemistry, 42,367-378; 2002, etc., is reacted with distanan, diborane, etc. under a transition metal catalyst such as palladium or nickel. Alternatively, after reacting a halogenated pyridine with an organolithium reagent such as butyllithium, it is reacted with chlorostannane, trialkoxyborane, or the like to obtain an organometallic reagent such as an organotin reagent, an organoboron reagent, or an organozinc reagent. Is synthesized by reacting with halogenated pyridine under a transition metal catalyst such as palladium or nickel.

  E) Tetrahedron, 43,895-904; 1987, Synthesis, 321-324; 1998, Organic Letters, 2,803-805; 2000, Journal of Organic Chemistry, 67, 443-449; 2002, etc. Raney nickel, palladium carbon, butyl lithium A method of dimerizing pyridine using a boron trifluoride ether complex or the like.

(2) Next, as a method for introducing a carbazolyl group, the following method can be employed depending on the bonding position.

(2-1) As a method for introducing an N-carbazolyl group, the methods described in the following a) to c) can be employed.
a) Aromatic 2 or more substituted fluoride (F-Ar-F) having a bipyridyl skeleton, a substituted or unsubstituted carbazole and a strong base such as sodium hydride, tert-butoxypotassium, n-butyllithium, etc. A method in which a reaction product (about 1.1 to 10 equivalents with respect to fluorine atoms) is stirred in a solution of tetrahydrofuran, dioxane, ether, N, N-dimethylformamide and the like for 1 to 60 hours with heating under reflux.

b) Aromatic 2 or 2 or more substituted halides (X-Ar-X, preferably X = Br, I) having a bipyridyl skeleton and substituted or unsubstituted carbazole, copper powder, copper wire, copper halide (CuX (X = Cl, Br, I)), copper catalysts such as copper oxide (CuO) (about 0.1 to 5 equivalents relative to the halogen atom), potassium carbonate, calcium carbonate, potassium phosphate, cesium carbonate In the presence of a basic substance such as sodium tert-butoxy (about 1 to 10 equivalents relative to the halogen atom), in an inert gas stream, no solvent, or an aromatic solvent such as nitrobenzene, a solvent such as tetraglyme or polyethylene glycol Medium, stirring and mixing in a temperature range of 20 to 300 ° C. for 1 to 60 hours.

c) An aromatic 2 or 3 substituted halide (X-Ar-X, preferably X = Cl, Br, I) having a bipyridyl skeleton and a substituted or unsubstituted carbazole are converted into Pd ₂ (dba) ₃ (Pd = Palladium, dba = dibenzylideneacetone), Pd (dba) ₂ , palladium acetate and the like, bivalent palladium catalyst, BINAP (= 2,2′-bis (diphenylphosphino-1,1′-binaphthyl), tri (Tert-butyl) phosphine, triphenylphosphine, 1,2-bis (diphenylphosphino) ethane, 1,3-bis (diphenylphosphino) propane, 1,3-bis (diphenylphosphino) butane, dppf ( = 1,1'-bis (diphenylphosphino) ferrocene) or a combination of ligands such as Pd (PPh ₃ ) ₄ (PPh ₃ = A trivalent phosphine) or other catalyst such as a palladium chloride complex such as PdCl ₂ (dppf) ₂ (about 0.001 to 1 equivalent to a halogen atom) and tert-butoxy potassium , Tert-butoxy sodium, potassium carbonate, cesium carbonate, triethylamine, etc., in the presence of a basic substance (usually 1.1 to 10 equivalents relative to the halogen atom), tetrahydrofuran, dioxane, dimethoxyethane, N, N-dimethylformamide , Stirring in a solvent such as dimethyl sulfoxide, xylene, toluene, triethylamine at 30 to 200 ° C. for 1 to 60 hours.

(2-2) As a method for introducing a 2-8-carbazolyl group, a coupling reaction between a carbazole having a halogen atom such as chlorine, bromine and iodine at a position to which the linking group Q is linked, and an aryl borate, or A coupling reaction between an aryl halide and a carbazolyl borate can be used. Specifically, a known coupling method (“Palladium in Heterocyclic Chemistry: A guide for the Synthetic Chemist” (second edition, 2002, Jie Jack Li and Gordon W. Gribble, Pergamon), “Organic synthesis pioneered by transition metals, its various reaction forms and latest results” (1997, Junjiro, Kagaku Dojinsha), “Bolhardt Shore Modern Organic Chemistry (2004, KPCVollhardt, Kagaku Dojinsha)) and the like can be used.

(3) In addition to the above-described synthesis method examples, the formation of a linking group (that is, Q ¹ , Q ² ) that connects the carbazolyl group and the bipyridyl skeleton in the present invention is not limited to a known cup. Ring method (“Palladium in Heterocyclic Chemistry: A guide for the Synthetic Chemist” (2nd edition, 2002, Jie Jack Li and Gordon W. Gribble, Pergamon), “Organic synthesis pioneered by transition metals. Of the rings described in or cited in "The Achievements of" (1997, Kenjiro, Kagaku Dojinsha), "Bolhard Shore Modern Organic Chemistry" (2004, KPCVollhardt, Kagaku Dojinsha)) ) Reaction) can be used.

(4) Compound purification methods include “Separation and Purification Technology Handbook” (1993, edited by The Chemical Society of Japan), “Advanced Separation of Trace Components and Difficulty Substances by Chemical Conversion Methods” (1988, ) Issued by IPC), or the methods described in the section “Separation and purification” in “Experimental Chemistry Course (4th edition) 1” (1990, edited by The Chemical Society of Japan) Is available. Specifically, extraction (including suspension washing, boiling washing, ultrasonic washing, acid-base washing), adsorption, occlusion, melting, crystallization (including recrystallization from solvent, reprecipitation), distillation (atmospheric pressure) Distillation, vacuum distillation), evaporation, sublimation (atmospheric pressure sublimation, vacuum sublimation), ion exchange, dialysis, filtration, ultrafiltration, reverse osmosis, pressure osmosis, zone lysis, electrophoresis, centrifugation, flotation separation, sedimentation separation, Magnetic separation, various chromatography (shape classification: column, paper, thin layer, capillary. Mobile phase classification: gas, liquid, micelle, supercritical fluid. Separation mechanism: adsorption, distribution, ion exchange, molecular sieve, chelate, gel filtration , Exclusion, affinity.).

(5) Gas chromatograph (GC), high performance liquid chromatograph (HPLC), high performance amino acid analyzer (AAA), capillary electrophoresis measurement (CE), size exclusion chromatograph ( SEC), gel permeation chromatograph (GPC), cross-fractionation chromatograph (CFC) mass spectrometry (MS, LC / MS, GC / MS, MS / MS), nuclear magnetic resonance apparatus (NMR ( ¹ HNMR, ¹³ CNMR)) , Fourier transform infrared spectrophotometer (FT-IR), ultraviolet visible near infrared spectrophotometer (UV.VIS, NIR), electron spin resonance apparatus (ESR), transmission electron microscope (TEM-EDX), electron beam microanalyzer ( EPMA), metal element analysis (ion chromatography, inductively coupled plasma-emission spectroscopy (ICP-AES) atomic absorption) Analysis (AAS) X-ray fluorescence analyzer (XRF)), non-metallic element analysis, trace component analysis (ICP-MS, GF-AAS, GD-MS) and the like can be applied as necessary.

(Charge transport material)
Since the organic compound of the present invention has excellent charge transportability, it is useful as a charge transport material. The charge transport material containing the organic compound of the present invention has excellent film forming properties, charge transport properties, light emitting characteristics, and heat resistance.

[Organic electroluminescence device]
Next, the organic electroluminescent element of the present invention using the organic compound of the present invention as described above will be described.

  The organic electroluminescent device of the present invention comprises an organic electroluminescent device having an anode, a cathode, and an organic light emitting layer provided between both electrodes on a substrate, and the organic compound is contained between the anode and the cathode. The organic compound of the present invention is preferably contained in the organic light emitting layer, and particularly preferably in the organic light emitting layer, the organic compound of the present invention is used as a host material, and the host material is The organic metal complex is doped.

  When using the organic compound of this invention as a host material of the organic light emitting layer of an organic electroluminescent element in this way, 1 type may be used independently and may be used in combination of 2 or more type.

Hereinafter, an example of the structure of the organic electroluminescent element of the present invention will be described with reference to the drawings. However, the structure of the organic electroluminescent element of the present invention is not limited to the one shown in the drawings.
1 to 3 are cross-sectional views schematically showing an example of the structure of the organic electroluminescent device of the present invention, wherein 1 is a substrate, 2 is an anode, 3 is a hole injection layer (anode buffer layer), and 4 is a hole transport. Layers 5, 5 are light-emitting layers, 6 is a hole blocking layer, 7 is an electron transport layer, and 8 is a cathode.

(substrate)
The substrate 1 serves as a support for the organic electroluminescent element, and a quartz or glass plate, a metal plate or a metal foil, a plastic film, a sheet, or the like is used. In particular, a glass plate or a transparent synthetic resin plate or film such as polyester, polymethacrylate, polycarbonate, polysulfone or the like is preferable. When using a synthetic resin substrate, it is necessary to pay attention to gas barrier properties. If the gas barrier property of the substrate is too small, the organic electroluminescent element may be deteriorated by the outside air that has passed through the substrate, which is not preferable. For this reason, a method of providing a gas barrier property by providing a dense silicon oxide film or the like on at least one surface of the synthetic resin substrate is also a preferable method.

(anode)
An anode 2 is provided on the substrate 1. The anode 2 plays a role of hole injection into the hole transport layer 4. The anode 2 is usually a metal such as aluminum, gold, silver, nickel, palladium, or platinum, a metal oxide such as indium oxide, tin oxide, zinc oxide, indium-tin composite oxide, indium-zinc composite oxide, or iodine. It is composed of a metal halide such as copper halide, carbon black, or a conductive polymer such as poly (3-methylthiophene), polypyrrole, or polyaniline. In general, the anode 2 is often formed by a sputtering method, a vacuum deposition method, or the like. Further, when the anode 2 is formed of metal fine particles such as silver, fine particles such as copper iodide, carbon black, conductive metal oxide fine particles, and conductive polymer fine powder, It can also be formed by dispersing and coating on the substrate 1. Further, when the anode 2 is formed with a conductive polymer, a polymerized thin film can be formed directly on the substrate 1 by electrolytic polymerization, or a conductive polymer can be applied on the substrate 1 (Appl). Phys. Lett., 60, 2711, 1992).

The anode 2 usually has a single-layer structure, but it can also have a laminated structure made of a plurality of materials if desired.

  The thickness of the anode 2 varies depending on the required transparency. When transparency is required, the visible light transmittance is usually 60% or more, preferably 80% or more. In this case, the thickness of the anode is usually 5 nm or more, preferably 10 nm or more, and usually 1000 nm or less, preferably about 500 nm or less. When opaqueness is acceptable, the thickness of the anode 2 is arbitrary, and if desired, it may be formed of metal and serve as the substrate 1.

(Hole transport layer)
In the element having the configuration shown in FIG. 1, a hole transport layer 4 is provided on the anode 2. As conditions required for the material of the hole transport layer, it is necessary that the material has a high hole injection efficiency from the anode 2 and can efficiently transport the injected holes. For this purpose, the ionization potential is low, the transparency to visible light is high, the hole mobility is high, the stability is high, and impurities that become traps are unlikely to be generated during manufacturing or use. Required. Further, in order to contact the light emitting layer 5, it is required not to quench the light emitted from the light emitting layer 5 or to form an exciplex with the light emitting layer 5 to reduce the efficiency. In addition to the above general requirements, when the application for in-vehicle display is considered, the element is further required to have heat resistance. Therefore, a material having a glass transition temperature of 85 ° C. or higher is desirable.

  As such a hole transporting material, 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl is used similarly to the hole transporting material used for the host material of the light emitting layer 5. Aromatic diamines containing two or more representative tertiary amines and having two or more condensed aromatic rings substituted with nitrogen atoms (Japanese Patent Laid-Open No. 5-234681), 4,4 ′, 4 ″ -tris ( Aromatic amine compounds having a starburst structure such as 1-naphthylphenylamino) triphenylamine (J. Lumin., 72-74, 985, 1997), a triphenylamine tetramer Spiro compounds such as compounds (Chem. Commun., 2175, 1996), 2,2 ′, 7,7′-tetrakis- (diphenylamino) -9,9′-spirobifluorene (Synth. Metals, 91, pp. 209 pp., 1997), 4,4'-N, such as a carbazole derivative such as N'- dicarbazole biphenyl. These compounds may be used individually by 1 type, and may be used in mixture of multiple types as needed.

  In addition to the above compounds, polyarylene ether sulfone (Polym. Adv. Tech.) Containing polyvinyl carbazole, polyvinyl triphenylamine (Japanese Patent Laid-Open No. 7-53953), and tetraphenylbenzidine as the material of the hole transport layer 4 is used. , 7, p. 33, 1996).

  The hole transport layer 4 may be formed by a normal coating method such as a spray method, a printing method, a spin coating method, a dip coating method, or a die coating method, a wet film forming method such as various printing methods such as an ink jet method or a screen printing method, or a vacuum. It can be formed by a dry film formation method such as a vapor deposition method.

  In the case of the coating method, an additive such as a binder resin or a coating property improving agent that does not trap holes is added to one or more of the hole transport materials, if necessary, and dissolved in a suitable solvent. A solution is prepared, applied onto the anode 2 by a method such as spin coating, and dried to form the hole transport layer 4. Examples of the binder resin include polycarbonate, polyarylate, and polyester. When the amount of the binder resin added is large, the hole mobility is lowered. Therefore, the smaller amount is desirable, and the content in the hole transport layer is usually preferably 50% by weight or less.

In the case of the vacuum evaporation method, the hole transport material is put in a crucible installed in a vacuum vessel, the inside of the vacuum vessel is evacuated to about 10 ⁻⁴ Pa with a suitable vacuum pump, and then the crucible is heated, The hole transport material is evaporated and a hole transport layer 4 is formed on the substrate 1 on which the anode 2 is formed, which is placed facing the crucible.

  The thickness of the hole transport layer 4 is usually 5 nm or more, preferably 10 nm or more, and is usually 300 nm or less, preferably 100 nm or less. In order to uniformly form such a thin film, a vacuum deposition method is generally used.

(Light emitting layer)
In the element shown in FIG. 1, a light emitting layer 5 is provided on the hole transport layer 4. The light emitting layer 5 is a recombination of holes injected from the anode 2 and moving through the hole transport layer 4 and electrons injected from the cathode and moved through the hole blocking layer 6 between the electrodes to which an electric field is applied. It is formed of a luminescent material that emits strong light when excited by. Usually, the light emitting layer 5 includes a dopant material and a host material which are light emitting substances. Note that in this specification, a material included in the light-emitting layer, such as a dopant material or a host material, is referred to as a light-emitting layer material.

  The light emitting layer material used for the light emitting layer 5 has a stable thin film shape, exhibits a high emission (fluorescence or phosphorescence) quantum yield in the solid state, and can efficiently transport holes and / or electrons. It must be a compound. Further, it is required to be a compound that is electrochemically and chemically stable and does not easily generate impurities as traps during production or use.

Further, in the present invention, as described in the description of the hole blocking layer described later, light emission having a first oxidation potential smaller than the first oxidation potential obtained in cyclic voltammetry measurement of the hole blocking material. Substance, especially (oxidation potential of hole blocking material) − (oxidation potential of light emitting layer material) ≧ 0.1V
(Reduction potential of hole blocking material) ≧ (Reduction potential of luminescent substance)
It is preferable to use a light emitting layer material that satisfies the above. However, in the above formula, when the light emitting layer 5 includes a host material and a dopant material, the oxidation or reduction potential of the light emitting layer material is the oxidation or reduction potential of the host material.

  As a material that satisfies such conditions and forms a light emitting layer that emits fluorescence, a metal complex such as an aluminum complex of 8-hydroxyquinoline (Japanese Patent Laid-Open No. 59-194393), 10-hydroxybenzo [h] quinoline Metal complexes (JP-A-6-322362), bisstyrylbenzene derivatives (JP-A-1-245087, JP-A-2-222484), bisstyrylarylene derivatives (JP-A-2-247278), (2- Hydroxyphenyl) benzothiazole metal complexes (Japanese Patent Laid-Open No. 8-315983), silole derivatives, and the like. These light emitting layer materials are usually laminated on the hole transport layer by a vacuum deposition method. Of the hole transport layer materials described above, an aromatic amine compound having a light-emitting property can also be used as the light-emitting layer material.

  For the purpose of improving the luminous efficiency of the device and changing the emission color, for example, doping a fluorescent dye for lasers such as coumarin with an aluminum complex of 8-hydroxyquinoline as a host material (J. Appl. Phys., Volume 65). 3610 (1989)). This doping technique can also be applied to the light emitting layer 5, and various fluorescent dyes can be used as a doping material in addition to coumarin. Examples of fluorescent dyes that emit blue light include perylene, pyrene, anthracene, coumarin, and derivatives thereof. Examples of the green fluorescent dye include quinacridone derivatives and coumarin derivatives. Examples of yellow fluorescent dyes include rubrene and perimidone derivatives. Examples of red fluorescent dyes include DCM compounds, benzopyran derivatives, rhodamine derivatives, benzothioxanthene derivatives, azabenzothioxanthene and the like.

  Other than the above-mentioned fluorescent dyes for doping, depending on the host material, listed in Laser Research, 8, 694, 803, 958 (1980); 9, 9, 85 (1981). Fluorescent dyes and the like that can be used as a doping material for the light emitting layer.

The amount by which the fluorescent dye is doped with respect to the host material is preferably 10 ⁻³ wt% or more, more preferably 0.1 wt% or more. Moreover, 10 weight% or less is preferable and 3 weight% or less is more preferable. If the lower limit is not reached, it may not be possible to contribute to improving the luminous efficiency of the device. If the upper limit is exceeded, concentration quenching may occur, leading to a reduction in luminous efficiency.

  However, as described above, the organic compound of the present invention has both a portion mainly responsible for hole transport and a portion mainly responsible for electron transport, and therefore has both excellent hole transportability and electron transportability. The organic compound is suitable as a host material for the organic light emitting layer of the organic electroluminescence device because it has excellent electrical redox durability and a high triplet excitation level. The organic light emitting layer of the organic electroluminescent element preferably contains the organic compound of the present invention as a host material, and the host material is doped with an organometallic complex suitable as a light emitting substance for the reasons described later.

  In the present invention, the dopant material used for the light emitting layer is preferably an organometallic complex containing a metal selected from Groups 7 to 11 of the periodic table. The T1 (excited triplet level) of the metal complex is preferably lower than the T1 of the organic compound of the present invention used as the host material from the viewpoint of luminous efficiency. Furthermore, since light emission occurs in the dopant material, chemical stabilization such as redox is also required.

Preferred examples of the metal in the phosphorescent organometallic complex containing a metal selected from Groups 7 to 11 of the periodic table include ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum, and gold. Preferred examples of these organometallic complexes include compounds represented by the following general formula (V) or general formula (VI).
MLk-jL'j (V)
(In the formula, M represents a metal, k represents a valence of the metal, L and L ′ represent a bidentate ligand, and j represents 0, 1 or 2.)

（式中、Ｍ⁷は金属、Ｔは炭素又は窒素を表す。Ｔが窒素の場合はＲ¹⁴、Ｒ¹⁵は無く、Ｔが炭素の場合はＲ¹⁴、Ｒ¹⁵は水素原子、ハロゲン原子、アルキル基、アラルキル基、アルケニル基、シアノ基、アミノ基、アシル基、アルコキシカルボニル基、カルボキシル基、アルコキシ基、アルキルアミノ基、アラルキルアミノ基、ハロアルキル基、水酸基、アリールオキシ基、置換基を有していても良い芳香族炭化水素基又は芳香族複素環基を表す。
Ｒ¹²、Ｒ¹³は水素原子、ハロゲン原子、アルキル基、アラルキル基、アルケニル基、シアノ基、アミノ基、アシル基、アルコキシカルボニル基、カルボキシル基、アルコキシ基、アルキルアミノ基、アラルキルアミノ基、ハロアルキル基、水酸基、アリールオキシ基、置換基を有していても良い芳香族炭化水素基又は芳香族複素環基を表し、互いに連結して環を形成しても良い。）

(In the formula, M ⁷ represents a metal, T represents carbon or nitrogen. When T is nitrogen, there are no R ¹⁴ and R ¹⁵ , and when T is carbon, R ¹⁴ and R ¹⁵ represent a hydrogen atom, a halogen atom, and an alkyl. Group, aralkyl group, alkenyl group, cyano group, amino group, acyl group, alkoxycarbonyl group, carboxyl group, alkoxy group, alkylamino group, aralkylamino group, haloalkyl group, hydroxyl group, aryloxy group, substituent Represents an aromatic hydrocarbon group or an aromatic heterocyclic group.
R ¹² and R ¹³ are hydrogen atom, halogen atom, alkyl group, aralkyl group, alkenyl group, cyano group, amino group, acyl group, alkoxycarbonyl group, carboxyl group, alkoxy group, alkylamino group, aralkylamino group, haloalkyl group Represents an aromatic hydrocarbon group or an aromatic heterocyclic group which may have a hydroxyl group, an aryloxy group or a substituent, and may be linked to each other to form a ring. )

（環Ｅ１及び環Ｅ１’は各々独立に、芳香族炭化水素基又は芳香族複素環基を表し、置換基を有していても良い。環Ｅ２及び環Ｅ２’は含窒素芳香族複素環基を表し、置換基を有していても良い。Ｒ²¹、Ｒ²²及びＲ²³はそれぞれハロゲン原子；アルキル基；アルケニル基；アルコキシカルボニル基；メトキシ基；アルコキシ基；アリールオキシ基；ジアルキルアミノ基；ジアリールアミノ基；カルバゾリル基；アシル基；ハロアルキル基又はシアノ基を表す。） In the general formula (V), the bidentate ligands L and L ′ each represent a ligand having the following partial structure.

(Ring E1 and Ring E1 ′ each independently represent an aromatic hydrocarbon group or an aromatic heterocyclic group, which may have a substituent. Ring E2 and Ring E2 ′ are nitrogen-containing aromatic heterocyclic groups. Each of R ²¹ , R ²² and R ²³ is a halogen atom, an alkyl group, an alkenyl group, an alkoxycarbonyl group, a methoxy group, an alkoxy group, an aryloxy group, a dialkylamino group; A diarylamino group; a carbazolyl group; an acyl group; a haloalkyl group or a cyano group.)

  More preferable examples of the compound represented by the general formula (V) include compounds represented by the following general formulas (Va), (Vb) and (Vc).

（式中、Ｍ⁴は金属、ｋは該金属の価数を表す。環Ｅ１は置換基を有していても良い芳香族炭化水素基を表し、環Ｅ２は置換基を有していても良い含窒素芳香族複素環基を表す。）

(Wherein M ⁴ represents a metal, k represents a valence of the metal, ring E1 represents an aromatic hydrocarbon group which may have a substituent, and ring E2 may have a substituent. Represents a good nitrogen-containing aromatic heterocyclic group.)

（式中、Ｍ⁵は金属、ｋは該金属の価数を表す。環Ｅ１は置換基を有していても良い芳香族炭化水素基又は芳香族複素環基を表し、環Ｅ２は置換基を有していても良い含窒素芳香族複素環基を表す。）

(Wherein M ⁵ represents a metal, k represents a valence of the metal, ring E1 represents an aromatic hydrocarbon group or aromatic heterocyclic group which may have a substituent, and ring E2 represents a substituent. Represents a nitrogen-containing aromatic heterocyclic group which may have

（式中、Ｍ⁶は金属、ｋは該金属の価数を表し、ｊは０又は１又は２を表す。環Ｅ１及び環Ｅ１’は各々独立に、置換基を有していても良い芳香族炭化水素基又は芳香族複素環基を表し、環Ｅ２及び環Ｅ２’は各々独立に、置換基を有していても良い含窒素芳香族複素環基を表す。）

(In the formula, M ⁶ represents a metal, k represents a valence of the metal, and j represents 0, 1 or 2. Each of ring E1 and ring E1 ′ is independently an aromatic which may have a substituent. Represents an aromatic hydrocarbon group or an aromatic heterocyclic group, and ring E2 and ring E2 ′ each independently represent a nitrogen-containing aromatic heterocyclic group which may have a substituent.)

  The ring E1 and ring E1 ′ of the compounds represented by the general formulas (Va), (Vb), (Vc) are preferably phenyl group, biphenyl group, naphthyl group, anthryl group, thienyl group, furyl group, benzothienyl. Group, benzofuryl group, pyridyl group, quinolyl group, isoquinolyl group, or carbazolyl group.

  Ring E2 and ring E2 ′ are preferably a pyridyl group, pyrimidyl group, pyrazyl group, triazyl group, benzothiazole group, benzoxazole group, benzimidazole group, quinolyl group, isoquinolyl group, quinoxalyl group, or phenanthridyl group. Can be mentioned.

  Examples of the substituent that the compounds represented by the general formulas (Va), (Vb), and (Vc) may have include a halogen atom such as a fluorine atom; a C 1-6 carbon atom such as a methyl group and an ethyl group An alkyl group; an alkenyl group having 2 to 6 carbon atoms such as a vinyl group; an alkoxycarbonyl group having 2 to 6 carbon atoms such as a methoxycarbonyl group and an ethoxycarbonyl group; an alkoxy group having 1 to 6 carbon atoms such as a methoxy group and an ethoxy group; An aryloxy group such as a phenoxy group and a benzyloxy group; a dialkylamino group such as a dimethylamino group and a diethylamino group; a diarylamino group such as a diphenylamino group; a carbazolyl group; an acyl group such as an acetyl group; A haloalkyl group; a cyano group, and the like, which may be linked to each other to form a ring.

  In addition, the substituent which ring E1 and the substituent which ring E2 has couple | bonds, or the substituent which ring E1 'and the substituent which ring E2' have couple | bond together may form one condensed ring, Examples of such a condensed ring include a 7,8-benzoquinoline group.

  As the substituent for ring E1, ring E1 ′, ring E2 and ring E2 ′, an alkyl group, an alkoxy group, an aromatic hydrocarbon group, a cyano group, a halogen atom, a haloalkyl group, a diarylamino group, or a carbazolyl group is more preferable. Can be mentioned.

M ⁴ to M ⁵ in the formulas (Va) and (Vb) are preferably ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum or gold. M ⁷ in the formula (VI) is preferably ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum or gold, and particularly preferably a divalent metal such as platinum or palladium.

  Specific examples of the organometallic complexes represented by the general formulas (V), (Va), (Vb) and (Vc) are shown below, but are not limited to the following compounds.

  Among the organometallic complexes represented by the general formulas (V), (Va), (Vb), and (Vc), a 2-arylpyridine-based ligand (2- A compound having an arylpyridine, a compound in which an arbitrary substituent is bonded to the arylpyridine, or a compound in which an arbitrary gas is condensed thereto is preferable.

  Specific examples of the organometallic complex represented by the general formula (VI) are shown below, but are not limited to the following compounds (in the following, Me represents a methyl group and Et represents an ethyl group).

  The molecular weight of such a phosphorescent dopant material is usually 4000 or less, preferably 3000 or less, more preferably 2000 or less, and usually 200 or more, preferably 300 or more, more preferably 400 or more. If the molecular weight exceeds this upper limit, the sublimation property is significantly reduced, which may cause problems when using an evaporation method when producing an electroluminescent device, or decrease in solubility in an organic solvent, or a synthesis process. With the increase in the impurity components generated in the process, it may be difficult to improve the purity of the material (that is, to remove the deterioration-causing substance), and when the molecular weight is below the lower limit, the glass transition temperature, the melting point, and the vaporization temperature. Etc., the heat resistance may be significantly impaired.

  When two or more of these dopant materials are used, it is preferable that the oxidation potential of the hole blocking material in the hole blocking layer is larger than that having the highest oxidation potential among the plurality of types of dopant materials. .

  As a host material used for a light emitting layer that exhibits phosphorescence using such an organometallic complex as a dopant material, one type of the organic compound of the present invention may be used alone, or two or more types may be mixed. May be used. Further, together with the organic compound of the present invention, the above-mentioned materials as host materials used for a light emitting layer exhibiting fluorescence emission, and carbazole derivatives such as 4,4′-N, N′-dicarbazole biphenyl (WO 00/70655) Gazette), tris (8-hydroxyquinoline) aluminum (USP 6,303,238 gazette), 2,2 ′, 2 ″-(1,3,5-benzenetolyl) tris [1-phenyl-1H-benz Imidazole] (Appl. Phys. Lett., 78, 1622, 2001), polyvinylcarbazole (Japanese Patent Laid-Open No. 2001-257076), or a combination of two or more thereof may be used. When the light emitting layer contains a host material other than the organic compound of the present invention, the content thereof is preferably 50% by weight or less based on the organic compound of the present invention.

  The amount of the organometallic complex contained as a dopant material in the light emitting layer is preferably 0.1% by weight or more, and more preferably 30% by weight or less. If the lower limit is not reached, it may not be possible to contribute to improving the luminous efficiency of the device. If the upper limit is exceeded, concentration quenching may occur due to the formation of dimers between organometallic complexes, etc., leading to a decrease in luminous efficiency. There is sex.

  The amount of the dopant material in the light emitting layer exhibiting phosphorescence tends to be preferably slightly larger than the amount of the fluorescent dye contained in the light emitting layer in a conventional device using fluorescence (singlet). Moreover, when a fluorescent pigment | dye is contained in a light emitting layer with a phosphorescent dopant material, 0.05 weight% or more is preferable and 0.1 weight% or more is more preferable. Moreover, 10 weight% or less is preferable and 3 weight% or less is more preferable.

  The thickness of the light emitting layer 5 is usually 3 nm or more, preferably 5 nm or more, and is usually 200 nm or less, preferably 100 nm or less.

  The light emitting layer 5 can also be formed by the same method as the hole transport layer 4.

  A method of doping the above-described fluorescent dye and / or phosphorescent dye (phosphorescent dopant material) as the dopant material into the organic compound of the present invention as the host material of the light emitting layer will be described below.

  In the case of coating, the organic compound of the present invention, a dopant material, and, if necessary, an additive such as a binder resin that does not become an electron trap or light emission quencher, and a coating property improving agent such as a leveling agent were added and dissolved. A coating solution is prepared, applied onto the hole transport layer 4 by a method such as spin coating, and dried to form the light emitting layer 5. Examples of the binder resin include polycarbonate, polyarylate, and polyester. When the amount of the binder resin added is large, the hole / electron mobility is lowered. Therefore, it is desirable that the amount is small, and the content in the light emitting layer is preferably 50 wt% or less.

In the case of the vacuum deposition method, the organic compound of the present invention is put in a crucible installed in a vacuum vessel, the dopant material is put in another crucible, and the inside of the vacuum vessel is made up to about 10 ⁻⁴ Pa with a suitable vacuum pump. After evacuation, each crucible is heated and evaporated simultaneously to form a layer on the substrate placed opposite the crucible. As another method, a mixture of the above materials in a predetermined ratio may be evaporated using the same crucible.

  When each of the above dopant materials is doped into the light emitting layer 5, it is uniformly doped in the film thickness direction of the light emitting layer, but there may be a concentration distribution in the film thickness direction. For example, it may be doped only in the vicinity of the interface with the hole transport layer 4, or conversely, it may be doped in the vicinity of the interface of the hole blocking layer 6.

The light emitting layer 5 can also be formed by the same method as the hole transport layer 4, but usually a vacuum deposition method is used.
In addition, the light emitting layer 5 may contain components other than the above in the range which does not impair the performance of this invention.

(Hole blocking layer)
In the element shown in FIG. 1, the hole blocking layer 6 is laminated on the light emitting layer 5 so as to be in contact with the cathode side interface of the light emitting layer 5.

  The hole blocking layer 6 can block the holes moving from the hole transport layer 4 from reaching the cathode 8, and efficiently inject the electrons injected from the cathode 8 toward the light emitting layer 5. It is preferably formed from a compound that can be transported to the surface. Therefore, the physical properties required for the material constituting the hole blocking layer 6 are required to have high electron mobility and low hole mobility. The hole blocking layer 6 has a function of confining holes and electrons in the light emitting layer 5 and improving luminous efficiency.

The ionization potential of the hole blocking layer 6 provided in the organic electroluminescence device of the present invention is based on the ionization potential of the light emitting layer 5 (the ionization potential of the host material when the light emitting layer 5 includes a host material and a dopant material). It is preferably greater than 0.1 eV. The ionization potential is defined by the energy required to emit electrons at the HOMO (highest occupied molecular orbital) level of the material to the vacuum level. The ionization potential can be defined directly by photoelectron spectroscopy or can be determined by correcting the electrochemically measured oxidation potential relative to the reference electrode. In the case of the latter method, for example, when a saturated sweet potato electrode (SCE) is used as a reference electrode, it is defined by the following formula (“Molecular Semiconductors”, Springer-Verlag, 1985, page 98).
Ionization potential = oxidation potential (vs. SCE) + 4.3 eV

Furthermore, the electron affinity (EA) of the hole blocking layer 6 provided in the organic electroluminescence device of the present invention is equal to the electron affinity of the light emitting layer 5 (when the light emitting layer 5 contains a host material and a dopant material, the host material). It is preferable that it is equal to or higher than the electron affinity. Similar to the ionization potential, the electron affinity is also defined by the energy at which the electrons in the vacuum level fall to the LUMO (lowest unoccupied molecular orbital) level of the material and stabilize, with the vacuum level as a reference. The electron affinity can be obtained by subtracting the optical band gap from the above-mentioned ionization potential, or similarly obtained from the electrochemical reduction potential by the following formula.
Electron affinity = reduction potential (vs. SCE) +4.3 eV
Therefore, the hole blocking layer 6 provided in the organic electroluminescent element of the present invention uses an oxidation potential and a reduction potential,
(Oxidation potential of hole blocking material) − (oxidation potential of light emitting layer material) ≧ 0.1V
(Reduction potential of hole blocking material) ≧ (Reduction potential of light emitting layer material)
It can also be expressed as

Furthermore, in the case of an element having an electron transport layer 7 described later, the electron affinity of the hole blocking layer 6 is preferably equal to or less than that of the electron transport layer 7. Therefore,
(Reduction potential of electron transport material) ≧ (Reduction potential of hole blocking material) ≧ (Reduction potential of light emitting layer material)
(Here, when a plurality of electron transport materials, hole blocking materials, or light emitting layer materials are used, one having the lowest reduction potential is used for comparison. Also, the light emitting layer 5 is used.) In the case where includes a host material and a dopant material, the host material having the lowest reduction potential is used for comparison.)

  As a hole blocking material satisfying such conditions, a mixed ligand complex represented by the following general formula (VII) is preferably used.

（式中、Ｒ¹⁰¹〜Ｒ¹⁰⁶は、各々独立に水素原子又は任意の置換基を表す。Ｍ^８はアルミニウム、ガリウム、インジウムから選ばれる金属原子を表す。Ｌ^５は以下に示す一般式（VIIａ）、（VIIｂ）、（VIIｃ）のいずれかで表される。

（式中、Ａｒ⁵¹〜Ａｒ⁵⁵は、各々独立に置換基を有していても良い芳香族炭化水素基又は置換基を有していても良い芳香族複素環基を表し、Ｚ^３はシリコン又はゲルマニウムを表す。）

(In the formula, R ^{101 to} R ¹⁰⁶ each independently represents a hydrogen atom or an arbitrary substituent. M ⁸ represents a metal atom selected from aluminum, gallium, and indium. L ⁵ represents a general formula (VIIa ), (VIIb), or (VIIc).

(In the formula, Ar ^{51 to} Ar ⁵⁵ each independently represents an aromatic hydrocarbon group which may have a substituent or an aromatic heterocyclic group which may have a substituent, and Z ³ represents silicon. Or represents germanium.)

In the general formula (VII), R ^{101 to} R ¹⁰⁶ each independently represents a hydrogen atom or an arbitrary substituent, preferably a hydrogen atom; a halogen atom such as chlorine or bromine; a carbon number such as a methyl group or an ethyl group. 1-6 alkyl groups; aralkyl groups such as benzyl groups; alkenyl groups having 2 to 6 carbon atoms such as vinyl groups; cyano groups; amino groups; acyl groups; alkoxy having 1 to 6 carbon atoms such as methoxy groups and ethoxy groups Group: alkoxycarbonyl group having 2 to 6 carbon atoms such as methoxycarbonyl group and ethoxycarbonyl group; carboxyl group; aryloxy group such as phenoxy group and benzyloxy group; dialkylamino group such as diethylamino group and diisopropylamino group; Diaralkylamino groups such as amino groups and diphenethylamino groups; α-haloalkyl groups such as trifluoromethyl groups; ; Which may have a substituent phenyl group, an aromatic hydrocarbon group such as a naphthyl group; which may have a substituent group thienyl group, an aromatic heterocyclic group such as pyridyl group.

  Examples of the substituent that the aromatic hydrocarbon group and the aromatic heterocyclic group may have include a halogen atom such as a fluorine atom; an alkyl group having 1 to 6 carbon atoms such as a methyl group and an ethyl group; and a carbon number such as a vinyl group. An alkenyl group having 2 to 6 carbon atoms; an alkoxycarbonyl group having 2 to 6 carbon atoms such as a methoxycarbonyl group and an ethoxycarbonyl group; an alkoxy group having 1 to 6 carbon atoms such as a methoxy group and an ethoxy group; a phenoxy group and a benzyloxy group Aryloxy groups; dialkylamino groups such as dimethylamino groups and diethylamino groups; acyl groups such as acetyl groups; haloalkyl groups such as trifluoromethyl groups; cyano groups and the like.

R ^{101 to} R ¹⁰⁶ are more preferably each independently a hydrogen atom, an alkyl group, a halogen atom or a cyano group. R ¹⁰⁴ is particularly preferably a cyano group.

In the general formulas (VIIa), (VIIb), and (VIIc), Ar ^{51 to} Ar ⁵⁵ are specifically, independently of each other, optionally substituted phenyl group, biphenyl group, naphthyl group, etc. And aromatic heterocyclic groups such as thienyl group and pyridyl group.

  Although the preferable specific example of a compound represented by the said general formula (VII) is shown below, it is not limited to these.

  In addition, these compounds may be used individually by 1 type in the hole-blocking layer 6, and may mix and use 2 or more types as needed.

  As the hole blocking material, in addition to the mixed ligand complex represented by the general formula (VII), a compound having at least one 1,2,4-triazole ring residue represented by the following structural formula: It can also be used.

  Specific examples of the compound having at least one 1,2,4-triazole ring residue represented by the above structural formula are shown below, but are not limited thereto.

  Examples of the hole blocking material further include compounds having at least one phenanthroline ring represented by the following structural formula.

  Specific examples of the compound having at least one phenanthroline ring represented by the above structural formula are shown below, but are not limited thereto.

  As the hole blocking material, it is preferable to use a compound having a pyridine ring having a substituent at the 2,4,6-position in one molecule. Specific examples include the following.

  The thickness of the hole blocking layer 6 is usually 0.3 nm or more, preferably 0.5 nm or more, and is usually 100 nm or less, preferably 50 nm or less.

  The hole blocking layer can also be formed by the same method as that for the 6-hole transport layer 4, but a vacuum deposition method is usually used.

  However, the organic compound used in the present invention is excellent as a host material for the light emitting layer of the organic electroluminescent device, and as shown in the examples described later, in the present invention, it is not necessary to provide a hole blocking layer. Sufficiently good characteristics can be obtained.

(cathode)
The cathode 8 serves to inject electrons into the light emitting layer 5 through the hole blocking layer 6. The material used for the cathode 8 can be the material used for the anode 2, but a metal having a low work function is preferable for efficient electron injection, such as tin, magnesium, indium, calcium, A suitable metal such as cesium, aluminum, silver, or an alloy thereof is used. Specific examples include low work function alloy electrodes such as magnesium-silver alloy, magnesium-indium alloy, and aluminum-lithium alloy.

The film thickness of the cathode 8 is usually the same as that of the anode 2.
For the purpose of protecting the cathode 8 made of a low work function metal, further laminating a metal layer having a high work function and stable to the atmosphere increases the stability of the device. For this purpose, metals such as aluminum, silver, copper, nickel, chromium, gold, platinum are used.

Furthermore, it is also possible to insert a very thin insulating film (0.1 to 5 nm) such as LiF, MgF ₂ , Li ₂ O at the interface between the cathode 8 and the light emitting layer 5 or the electron transport layer 7 to be described later. It is an effective method to improve (Appl. Phys. Lett., 70, 152, 1997; JP-A-10-74586; IEEE Trans. Electron. Devices, 44, 1245, 1997).

(Electron transport layer)
For the purpose of further improving the luminous efficiency of the device, it is preferable to provide an electron transport layer 7 between the hole blocking layer 6 and the cathode 8 as shown in FIGS. The electron transport layer 7 is formed of a compound that can efficiently transport electrons injected from the cathode 8 between electrodes to which an electric field is applied in the direction of the hole blocking layer 6.

Materials satisfying such conditions include metal complexes such as aluminum complexes of 8-hydroxyquinoline (Japanese Patent Laid-Open No. 59-194393), metal complexes of 10-hydroxybenzo [h] quinoline, oxadiazole derivatives, Styryl biphenyl derivative, silole derivative, 3- or 5-hydroxyflavone metal complex, benzoxazole metal complex, benzothiazole metal complex, trisbenzimidazolylbenzene (US Pat. No. 5,645,948), quinoxaline compound No. 207169), phenanthroline derivatives (Japanese Patent Laid-Open No. 5-331459), 2-t-butyl-9,10-N, N′-dicyanoanthraquinonediimine, n-type hydrogenated amorphous silicon carbide, n-type sulfide Examples include zinc and n-type zinc selenide.

  In addition, by doping an alkali metal into the electron transport material as described above (described in JP-A-10-270171, JP-A 2002-1000048, JP-A 2002-1000047, etc.) Is preferable.

  When such an electron transport layer 7 is formed, the electron affinity of the hole blocking layer 6 is preferably equal to or less than the electron affinity of the electron transport layer 7.

In addition, the reduction potential of the light emitting layer material in the light emitting layer 5, the hole blocking material of the hole blocking layer 6 and the electron transport material used for the electron transport layer satisfies the following relationship to adjust the light emitting region and drive This is preferable from the viewpoint of lowering the voltage.
(Reduction potential of electron transport material) ≧ (Reduction potential of hole blocking material) ≧ (Reduction potential of light emitting layer material)
Here, when a plurality of electron transport materials, hole blocking materials, or light emitting layer materials are used, the one having the lowest reduction potential is used for comparison. However, when the light emitting layer 5 contains a host material and a dopant material, the host material having the lowest reduction potential is used for comparison.

  The hole blocking material described above may be used for the electron transport layer 7. In that case, the electron transport layer 7 may be formed by using the aforementioned hole blocking material alone, or a plurality of them may be used in combination.

  The thickness of the electron transport layer 6 is usually 5 nm or more, preferably 10 nm or more, and is usually 200 nm or less, preferably 100 nm or less.

  The electron transport layer 7 is formed by laminating on the hole blocking layer 6 by a coating method or a vacuum vapor deposition method in the same manner as the hole transport layer 4, but a vacuum vapor deposition method is usually used.

(Hole injection layer)
For the purpose of further improving the efficiency of hole injection and improving the adhesion of the whole organic layer to the anode 2, as shown in FIG. 3, hole injection is performed between the hole transport layer 4 and the anode 2. Inserting layer 3 has also been done. By inserting the hole injection layer 3, the driving voltage of the initial element is lowered, and at the same time, an increase in voltage when the element is continuously driven with a constant current is suppressed.

  Conditions required for the material used for the hole injection layer 3 include that the contact with the anode 2 is good and a uniform thin film can be formed, and that the material is thermally stable, the melting point and the glass transition temperature are high, The melting point is preferably 300 ° C. or higher, and the glass transition temperature is preferably 100 ° C. or higher. Furthermore, the ionization potential is low, hole injection from the anode 2 is easy, and the hole mobility is high.

  For this purpose, as the material for the hole injection layer 3, porphyrin derivatives, phthalocyanine compounds (Japanese Patent Laid-Open No. 63-295695), hydrazone compounds, alkoxy-substituted aromatic diamine derivatives, p- (9- Anthryl) -N, N'-di-p-tolylaniline, polythienylene vinylene, poly-p-phenylene vinylene, polyaniline (Appl. Phys. Lett., 64, 1245, 1994), polythiophene (OpticalMaterials, 9, 125, 1998), organic compounds such as starbust aromatic triamine (Japanese Patent Laid-Open No. 4-308688), sputtered carbon film (Synth. Met., 91, 73, 1997) In addition, metal oxides such as vanadium oxide, ruthenium oxide, and molybdenum oxide (J. Phys. D, 29, 2750, 1996) have been reported.

In addition, a layer containing a hole injection / transporting low molecular organic compound and an electron accepting compound (described in JP-A-11-251067, JP-A-2000-159221, etc.), an aromatic amino group, etc. A layer obtained by doping the contained non-conjugated polymer compound with an electron-accepting compound as necessary (JP-A-11-135262, JP-A-11-283750, JP-A-2)
No. 000-36390, JP-A 2000-150168, JP-A 2001-223084, and WO 97/33193), or a layer containing a conductive polymer such as polythiophene (JP-A 10-92584) However, it is not limited to these.

  As the material of the hole injection layer 3, it is possible to use either low molecular or high molecular compounds.

Of the low molecular weight compounds, those often used include porphine compounds and phthalocyanine compounds. These compounds may have a central metal or may be metal-free. Preferable examples of these compounds include the following compounds.
Porphin,
5,10,15,20-tetraphenyl-21H, 23H-porphine,
5,10,15,20-tetraphenyl-21H, 23H-porphine cobalt (II),
5,10,15,20-tetraphenyl-21H, 23H-porphine copper (II),
5,10,15,20-tetraphenyl-21H, 23H-porphine zinc (II),
5,10,15,20-tetraphenyl-21H, 23H-porphine vanadium (IV) oxide,
5,10,15,20-tetra (4-pyridyl) -21H, 23H-porphine,
29H, 31H-phthalocyanine,
Copper (II) phthalocyanine,
Zinc (II) phthalocyanine,
Titanium phthalocyanine oxide,
Magnesium phthalocyanine,
Lead phthalocyanine,
Copper (II) 4,4'4 '', 4 '''-tetraaza-29H, 31H-phthalocyanine

  The hole injection layer 3 can also be formed into a thin film in the same manner as the hole transport layer 4, but in the case of an inorganic material, a sputtering method, an electron beam evaporation method, or a plasma CVD method is further used.

  When the hole injection layer 3 formed as described above is formed using a low molecular weight compound, the lower limit is usually 3 nm, preferably about 10 nm, and the upper limit is usually about 100 nm, preferably about 50 nm. It is.

  When a polymer compound is used as the material for the hole injection layer 3, for example, the polymer compound or the electron-accepting compound, and if necessary, a coating resin such as a binder resin or a leveling agent that does not trap holes if necessary. A coating solution in which an additive such as the above is added and dissolved is applied to the anode 2 by a normal coating method such as a spray method, a printing method, a spin coating method, a dip coating method, a die coating method, or an inkjet method. The hole injection layer 3 can be formed into a thin film by drying. Examples of the binder resin include polycarbonate, polyarylate, and polyester. Since there is a possibility that the hole mobility may be lowered when the content of the binder resin in the layer is large, it is desirable that the content is in the hole injection layer 3 to be 50% by weight or less.

  Alternatively, a thin film may be formed in advance on a medium such as a film, a support substrate, or a roll by the above-described thin film forming method, and the thin film on the medium is thermally or pressure transferred onto the anode 2. it can.

  As described above, the lower limit of the thickness of the hole injection layer 3 formed using the polymer compound is usually 5 nm, preferably about 10 nm, and the upper limit is usually about 1000 nm, preferably about 500 nm.

(Layer structure)
The organic electroluminescent device of the present invention has a structure opposite to that shown in FIG. 1, that is, a cathode 8, a hole blocking layer 6, a light emitting layer 5, a hole transport layer 4, and an anode 2 are laminated on the substrate 1 in this order. As described above, the organic electroluminescent element of the present invention can be provided between two substrates, at least one of which is highly transparent. Similarly, the layers can be stacked in the reverse order to the above-described layer configuration shown in FIG. Moreover, in any layer structure of FIGS. 1-3, you may have arbitrary layers other than the above in the range which does not deviate from the meaning of this invention, and also has the layer which has the function of said several layer together. By providing, it is possible to appropriately modify the layer structure, for example.

Alternatively, a top emission structure or a transmission type using a transparent electrode for both the cathode and anode, and a structure in which the layer configuration shown in FIG. 1 is stacked in multiple layers (a structure in which a plurality of light emitting units are stacked) is used. Is also possible. In that case, instead of the interfacial layer (between the light emitting units) (when the anode is ITO and the cathode is Al, the two layers), for example, V ₂ O ₅ is used as the charge generation layer (CGL). This is more preferable from the viewpoint of luminous efficiency and driving voltage.

  The present invention can be applied to any of an organic electroluminescent element having a single element, an element having a structure arranged in an array, and a structure having an anode and a cathode arranged in an XY matrix.

  EXAMPLES Next, although an Example demonstrates this invention further more concretely, this invention is not limited to description of a following example, unless the summary is exceeded.

[Synthesis example of organic compounds]
Synthesis examples of the organic compound of the present invention and organic compounds that can be used as the charge transport material of the present invention are shown in the following synthesis examples. In the following, the glass transition temperature (Tg) was determined by DSC measurement, the vaporization temperature was determined by TG-DTA measurement, and the melting point was determined by TG-DTA measurement.

窒素気流中、カルバゾール（７．００ｇ）、３−ブロモヨードベンゼン（１４．２ｇ）、銅粉末（２．６６ｇ）、炭酸カリウム（５．７９ｇ）、及びテトラグライム（１０ｍｌ）を、１４０℃に加熱下、５時間撹拌し、室温まで放冷した。反応終了後、反応液にクロロホルムを加え、不溶物を濾別した。濾液に含まれるクロロホルムを減圧留去し、シリカゲルカラムクロマトグラフィー（ｎ−ヘキサン／トルエン＝４／１）で精製した。減圧乾燥することにより、目的物１（１０．５ｇ、収率７８％）を無色粘調液体として得た。 (Synthesis Example 1)
(i) Synthesis of target 1

In a nitrogen stream, carbazole (7.00 g), 3-bromoiodobenzene (14.2 g), copper powder (2.66 g), potassium carbonate (5.79 g), and tetraglyme (10 ml) were heated to 140 ° C. The mixture was stirred for 5 hours and allowed to cool to room temperature. After completion of the reaction, chloroform was added to the reaction solution, and insoluble matters were separated by filtration. Chloroform contained in the filtrate was distilled off under reduced pressure and purified by silica gel column chromatography (n-hexane / toluene = 4/1). The target product 1 (10.5 g, yield 78%) was obtained as a colorless viscous liquid by drying under reduced pressure.

窒素気流中、目的物１（１０．５ｇ）、ビス（ピナコラートジボロン）（９．９３ｇ）、酢酸カリウム（１０．９ｇ）、及び脱水ジメチルスルホキシド（ＤＭＳＯ）（１９０ｍｌ）を、６０℃に加熱下、１５分間撹拌し、[１，１’−ビス（ジフェニルホスフィノ）フェロセン]ジクロロパラジウム（ＩＩ）ジクロロメタン錯体（０．７９９ｇ）を加え、８０℃に加熱下、９時間撹拌した。室温まで放冷した後、反応液に水（２５０ｍｌ）、及びトルエン（５００ｍｌ）を加え、攪拌した。水層をトルエンで２回再抽出した後、有機層を合わせ、硫酸マグネシウム及び活性白土を加えた。硫酸マグネシウム及び活性白土を濾別し、トルエンを減圧留去した。析出した結晶を冷メタノールで洗浄し、減圧乾燥することにより、目的物２（９．８６ｇ、収率８０％）を白色結晶として得た。 (ii) Synthesis of target 2

Heat the target compound 1 (10.5 g), bis (pinacolatodiboron) (9.93 g), potassium acetate (10.9 g), and dehydrated dimethyl sulfoxide (DMSO) (190 ml) to 60 ° C. in a nitrogen stream. Under stirring for 15 minutes, [1,1′-bis (diphenylphosphino) ferrocene] dichloropalladium (II) dichloromethane complex (0.799 g) was added, and the mixture was stirred for 9 hours while heating at 80 ° C. After cooling to room temperature, water (250 ml) and toluene (500 ml) were added to the reaction solution and stirred. The aqueous layer was re-extracted twice with toluene, the organic layers were combined, and magnesium sulfate and activated clay were added. Magnesium sulfate and activated clay were separated by filtration, and toluene was distilled off under reduced pressure. The precipitated crystals were washed with cold methanol and dried under reduced pressure to give the intended product 2 (9.86 g, yield 80%) as white crystals.

窒素気流中、６，６’−ジブロモ−２，２’−ビピリジル（１．５０ｇ）、目的物２（４．２３ｇ）、炭酸カリウム（３．９６ｇ）、エチレングリコールジメチルエーテル（１８ｍｌ）、及び水（６ｍｌ）を、６０℃に加熱下、１５分間撹拌し、テトラキス（トリフェニルホスフィン）パラジウム（０）（０．２７７ｇ）を加え、加熱還流下、８時間撹拌した。室温まで放冷した後、反応液にメタノール（１００ｍｌ）を加え、攪拌した。析出物を濾過により回収し、メタノール／水混合液で洗浄した後、減圧乾燥した。得られた結晶を、シリカゲルカラムクロマトグラフィー（ｎ−ヘキサン／塩化メチレン＝２／１）で精製した。更に、塩化メチレン／メタノール混合液で洗浄し、減圧乾燥することにより、目的物３（１．６３ｇ、収率５３％）を白色結晶として得た。この白色結晶１．５１ｇを昇華精製したところ、白色固体１．４１ｇが回収された。
ＤＥＩ−ＭＳ（m/z=638(M⁺)）より、目的物３であることを確認した。
このもののガラス転移温度は１１５℃、融点は２５２℃、気化温度は５０８℃であった。 (iii) Synthesis of target 3

In a nitrogen stream, 6,6′-dibromo-2,2′-bipyridyl (1.50 g), target product 2 (4.23 g), potassium carbonate (3.96 g), ethylene glycol dimethyl ether (18 ml), and water ( 6 ml) was stirred for 15 minutes while heating to 60 ° C., tetrakis (triphenylphosphine) palladium (0) (0.277 g) was added, and the mixture was stirred for 8 hours under heating to reflux. After allowing to cool to room temperature, methanol (100 ml) was added to the reaction mixture and stirred. The precipitate was collected by filtration, washed with a methanol / water mixture, and then dried under reduced pressure. The obtained crystals were purified by silica gel column chromatography (n-hexane / methylene chloride = 2/1). Further, the product was washed with a methylene chloride / methanol mixed solution and dried under reduced pressure to obtain the target product 3 (1.63 g, yield 53%) as white crystals. When 1.51 g of this white crystal was purified by sublimation, 1.41 g of a white solid was recovered.
From DEI-MS (m / z = 638 (M ⁺ )), it was confirmed to be the intended product 3.
This had a glass transition temperature of 115 ° C., a melting point of 252 ° C., and a vaporization temperature of 508 ° C.

窒素気流中、６，６’−ジブロモ−２，２’−ビピリジル（２．００ｇ）、２，５−ジフルオロフェニルボロン酸（２．４１ｇ）、炭酸カリウム（４．４０ｇ）、エチレングリコールジメチルエーテル（２５ｍｌ）、及び水（１３ｍｌ）を、６０℃に加熱下、１５分間撹拌し、テトラキス（トリフェニルホスフィン）パラジウム（０）（０．３６８ｇ）を加え、加熱還流下、６時間撹拌した。室温まで放冷した後、反応液にメタノール（１００ｍｌ）を加え、攪拌した。析出物を濾過により回収し、メタノール／水混合液で洗浄した後、減圧乾燥した。得られた結晶をクロロホルム（１５０ｍｌ）に溶解させた溶液に活性白土を加え、加熱還流下、１時間攪拌した。濾過により不溶物を濾別し、濾液を濃縮した。析出した結晶をメタノールで洗浄し、減圧乾燥することにより、目的物４（２．１６ｇ、収率８９％）を白色結晶として得た。 (Synthesis Example 2)
(i) Synthesis of target 4

In a nitrogen stream, 6,6′-dibromo-2,2′-bipyridyl (2.00 g), 2,5-difluorophenylboronic acid (2.41 g), potassium carbonate (4.40 g), ethylene glycol dimethyl ether (25 ml) ) And water (13 ml) were stirred for 15 minutes while heating to 60 ° C., tetrakis (triphenylphosphine) palladium (0) (0.368 g) was added, and the mixture was stirred for 6 hours while heating under reflux. After allowing to cool to room temperature, methanol (100 ml) was added to the reaction mixture and stirred. The precipitate was collected by filtration, washed with a methanol / water mixture, and then dried under reduced pressure. Activated clay was added to a solution obtained by dissolving the obtained crystals in chloroform (150 ml), and the mixture was stirred for 1 hour while heating under reflux. Insoluble materials were removed by filtration, and the filtrate was concentrated. The precipitated crystals were washed with methanol and dried under reduced pressure to obtain target product 4 (2.16 g, yield 89%) as white crystals.

窒素気流中、水素化ナトリウム（５５％，１．６５ｇ）の脱水Ｎ，Ｎ−ジメチルホルムアミド（１００ｍｌ）懸濁液にカルバゾール（６．３３ｇ）を添加し、８０℃に加熱下、１時間撹拌した後、目的物４（１．８０ｇ）を添加し、加熱還流下で９時間撹拌した。これに氷冷下、水（７０ｍｌ）、及びメタノール（７０ｍｌ）を加えて、析出した沈殿を濾別し、メタノール洗浄し、減圧乾燥した。得られた結晶をシリカゲルカラムクロマトグラフィー（クロロホルム）で精製した。更に、酢酸エチル及びクロロホルム／メタノール混合液で洗浄し、減圧乾燥することにより、目的物５（２．１５ｇ、収率４７％）を白色結晶として得た。この白色結晶１．７７ｇを昇華精製したところ、白色固体１．２０ｇが回収された。
ＤＥＩ−ＭＳ（m/z=968(M⁺)）より、目的物５であることを確認した。
このもののガラス転移温度は１８０℃、結晶化温度は２８８℃、融点は３６４℃、気化温度は５５３℃であった。 (ii) Synthesis of target 5

Carbazole (6.33 g) was added to a suspension of sodium hydride (55%, 1.65 g) in dehydrated N, N-dimethylformamide (100 ml) in a nitrogen stream, and the mixture was stirred at 80 ° C. for 1 hour. Thereafter, the desired product 4 (1.80 g) was added, and the mixture was stirred for 9 hours under heating to reflux. Under ice cooling, water (70 ml) and methanol (70 ml) were added thereto, and the deposited precipitate was separated by filtration, washed with methanol, and dried under reduced pressure. The obtained crystals were purified by silica gel column chromatography (chloroform). Furthermore, it wash | cleaned with ethyl acetate and chloroform / methanol liquid mixture, and the target object 5 (2.15g, 47% of yield) was obtained as a white crystal | crystallization by drying under reduced pressure. When 1.77 g of this white crystal was purified by sublimation, 1.20 g of a white solid was recovered.
From DEI-MS (m / z = 968 (M ⁺ )), it was confirmed to be the target product 5.
This had a glass transition temperature of 180 ° C., a crystallization temperature of 288 ° C., a melting point of 364 ° C., and a vaporization temperature of 553 ° C.

窒素気流中、２，５−ジブロモピリジン（３．００ｇ）、ビス（トリブチルチン）（３．５４ｍｌ）、及び脱水キシレン（１００ｍｌ）を、６０℃に加熱下、１５分間撹拌し、テトラキス（トリフェニルホスフィン）パラジウム（０）（０．３５１ｇ）を加え、加熱還流下、８時間撹拌した。室温まで放冷した後、反応液にクロロホルム（１００ｍｌ）を加え、攪拌した後、不溶物を濾別し、濾液に含まれるキシレン及びクロロホルムを減圧留去した。得られた残渣をシリカゲルカラムクロマトグラフィー（塩化メチレン／ヘキサン＝１／５〜１／１）で精製し、メタノールで洗浄後、減圧乾燥することにより、目的物６（０．５１ｇ、収率２５％）を白色結晶として得た。 (Synthesis Example 3)
(i) Synthesis of target 6

In a nitrogen stream, 2,5-dibromopyridine (3.00 g), bis (tributyltin) (3.54 ml), and dehydrated xylene (100 ml) were stirred at 60 ° C. for 15 minutes, and tetrakis (triphenyl Phosphine) palladium (0) (0.351 g) was added, and the mixture was stirred for 8 hours while heating under reflux. After allowing to cool to room temperature, chloroform (100 ml) was added to the reaction solution, and the mixture was stirred. The insoluble material was filtered off, and xylene and chloroform contained in the filtrate were distilled off under reduced pressure. The obtained residue was purified by silica gel column chromatography (methylene chloride / hexane = 1/5 to 1/1), washed with methanol, and then dried under reduced pressure to give the intended product 6 (0.51 g, yield 25%). ) Was obtained as white crystals.

窒素気流中、目的物６（０．４８ｇ）、カルバゾール（１．０２ｇ）、銅粉末（０．２９ｇ）、炭酸カリウム（１．０６ｇ）、及びテトラグライム（４ｍｌ）を、２００℃に加熱下、８時間撹拌し、室温まで放冷した。反応終了後、反応液にクロロホルム（２００ｍｌ）を加え、不溶物を濾別した。濾液に含まれるクロロホルムを減圧留去し、シリカゲルカラムクロマトグラフィー（ｎ−ヘキサン／塩化メチレン＝１／１）で精製した。酢酸エチル及びメタノールで洗浄後、減圧乾燥することにより、目的物６（０．４２ｇ、収率５７％）を薄黄色結晶として得た。この薄黄色結晶０．４２ｇを昇華精製したところ、薄黄色固体０．２２ｇが回収された。
ＤＥＩ−ＭＳ（m/z=486(M⁺)）より、目的物７であることを確認した。
このものの融点は３２３℃、気化温度は４４３℃であった。 (ii) Synthesis of target 7

In a nitrogen stream, the target product 6 (0.48 g), carbazole (1.02 g), copper powder (0.29 g), potassium carbonate (1.06 g), and tetraglyme (4 ml) were heated to 200 ° C., The mixture was stirred for 8 hours and allowed to cool to room temperature. After completion of the reaction, chloroform (200 ml) was added to the reaction solution, and insoluble matters were filtered off. Chloroform contained in the filtrate was distilled off under reduced pressure and purified by silica gel column chromatography (n-hexane / methylene chloride = 1/1). After washing with ethyl acetate and methanol, drying under reduced pressure gave the target product 6 (0.42 g, yield 57%) as light yellow crystals. Sublimation purification of 0.42 g of the pale yellow crystals yielded 0.22 g of a pale yellow solid.
From DEI-MS (m / z = 486 (M ⁺ )), it was confirmed to be the target product 7.
This had a melting point of 323 ° C. and a vaporization temperature of 443 ° C.

窒素気流中、２，５−ジブロモピリジン（１９．５ｇ）、テトラキス（トリフェニルホスフィン）パラジウム（０）（４．３３ｇ）、及びテトラヒドロフラン（ＴＨＦ）（７５ｍｌ）の混合物を０℃に冷却し、２−ピリジルジンクブロマイドの０．５ＭのＴＨＦ溶液（１５０ｍｌ）を滴下した後、室温まで昇温し、７．５時間攪拌した。反応混合物に、水（４００ｍｌ）にエチレンジアミン四酢酸（ＥＤＴＡ）（２０ｇ）、及び炭酸ナトリウム（２０ｇ）を溶解させた水溶液を加えた後、クロロホルム（３００ｍｌ）で２回抽出した。有機層を硫酸マグネシウムで乾燥、濃縮した後、カラムクロマトグラフィー（塩化メチレン／酢酸エチル＝１／０〜２０／１）で精製することにより、目的物８（７．２７ｇ、収率４１％）を得た。 (Synthesis Example 4)
(i) Synthesis of target 8

In a nitrogen stream, a mixture of 2,5-dibromopyridine (19.5 g), tetrakis (triphenylphosphine) palladium (0) (4.33 g), and tetrahydrofuran (THF) (75 ml) was cooled to 0 ° C. and 2 -A 0.5 M THF solution (150 ml) of pyridyl zinc bromide was added dropwise, and then the mixture was warmed to room temperature and stirred for 7.5 hours. An aqueous solution in which ethylenediaminetetraacetic acid (EDTA) (20 g) and sodium carbonate (20 g) were dissolved in water (400 ml) was added to the reaction mixture, followed by extraction twice with chloroform (300 ml). The organic layer was dried over magnesium sulfate, concentrated, and purified by column chromatography (methylene chloride / ethyl acetate = 1/0 to 20/1) to give the desired product 8 (7.27 g, yield 41%). Obtained.

窒素気流中、目的物８（４−ブロモ−２，２’−ビピリジル）（２．４０ｇ）、２，５−ジフルオロフェニルボロン酸（２．９４ｇ）、炭酸カリウム（４．２３ｇ）、エチレングリコールジメチルエーテル（２０ｍｌ）、及び水（１０ｍｌ）を、６０℃に加熱下、１５分間撹拌し、テトラキス（トリフェニルホスフィン）パラジウム（０）（０．２９４ｇ）を加え、加熱還流下、８時間撹拌した。室温まで放冷した後、反応液に水（１５０ｍｌ）を加え、析出物を濾過により回収し、メタノール／水混合液で洗浄した後、減圧乾燥した。得られた結晶をトルエン（１５０ｍｌ）に溶解させた溶液に活性白土を加え、加熱還流下、１時間攪拌した。濾過により不溶物を濾別し、濾液を濃縮した。析出した結晶を冷エタノールで洗浄し、減圧乾燥することにより、目的物９（０．７９ｇ、収率２９％）を白色結晶として得た。 (ii) Synthesis of target 9

In a nitrogen stream, the target product 8 (4-bromo-2,2′-bipyridyl) (2.40 g), 2,5-difluorophenylboronic acid (2.94 g), potassium carbonate (4.23 g), ethylene glycol dimethyl ether (20 ml) and water (10 ml) were stirred for 15 minutes while heating to 60 ° C., tetrakis (triphenylphosphine) palladium (0) (0.294 g) was added, and the mixture was stirred for 8 hours under heating to reflux. After cooling to room temperature, water (150 ml) was added to the reaction solution, and the precipitate was collected by filtration, washed with a methanol / water mixture, and then dried under reduced pressure. Activated clay was added to a solution obtained by dissolving the obtained crystals in toluene (150 ml), and the mixture was stirred for 1 hour while heating under reflux. Insoluble materials were removed by filtration, and the filtrate was concentrated. The precipitated crystals were washed with cold ethanol and dried under reduced pressure to give the intended product 9 (0.79 g, yield 29%) as white crystals.

窒素気流中、水素化ナトリウム（５５％，０．７２３ｇ）の脱水Ｎ，Ｎ−ジメチルホルムアミド（３０ｍｌ）懸濁液にカルバゾール（２．７７ｇ）を添加し、８０℃に加熱下、３０分撹拌した後、目的物９（４−（２，５−ジフルオロフェニル）−２，２’−ビピリジル）（２．４０ｇ）を添加し、加熱還流下で９時間撹拌した。これに氷冷下、水（７０ｍｌ）、及びメタノール（７０ｍｌ）を加えて、析出した沈殿を濾別し、メタノール洗浄し、減圧乾燥した。得られた結晶をシリカゲルカラムクロマトグラフィー（クロロホルム／アセトン＝１／０〜２０／１）で精製した。さらに、エタノールで洗浄し、減圧乾燥することにより、目的物５（０．３２２ｇ、収率１９％）を白色結晶として得た。
ＤＥＩ−ＭＳ（m/z=562(M⁺)）より、目的物１０であることを確認した。 (iii) Synthesis of target product 10

Carbazole (2.77 g) was added to a dehydrated N, N-dimethylformamide (30 ml) suspension of sodium hydride (55%, 0.723 g) in a nitrogen stream, and the mixture was stirred at 80 ° C. for 30 minutes while heating. Then, the target product 9 (4- (2,5-difluorophenyl) -2,2′-bipyridyl) (2.40 g) was added, and the mixture was stirred with heating under reflux for 9 hours. Under ice cooling, water (70 ml) and methanol (70 ml) were added thereto, and the deposited precipitate was separated by filtration, washed with methanol, and dried under reduced pressure. The obtained crystals were purified by silica gel column chromatography (chloroform / acetone = 1/0 to 20/1). Further, the product was washed with ethanol and dried under reduced pressure to obtain the target product 5 (0.322 g, yield 19%) as white crystals.
From DEI-MS (m / z = 562 (M ⁺ )), it was confirmed to be the target product 10.

ベンズアルデヒド（１０．６ｇ）、ジアセチル（４．３ｇ）、及びピペリジン（０．５ｍｌ）をエタノール（５０ｍｌ）に溶解し、加熱還流下、２．５時間攪拌した。放冷、冷蔵庫で冷却後、得られた結晶を濾取した。これをメタノールで洗浄後、乾燥し、目的物１１（１．３９ｇ）を得た。 (Synthesis Example 5)
(i) Synthesis of target 11

Benzaldehyde (10.6 g), diacetyl (4.3 g), and piperidine (0.5 ml) were dissolved in ethanol (50 ml), and the mixture was stirred with heating under reflux for 2.5 hours. After standing to cool and cooling in the refrigerator, the obtained crystals were collected by filtration. This was washed with methanol and dried to obtain the intended product 11 (1.39 g).

４−ブロモ−フェナシルピリジニウムブロミド（３．５６ｇ）、目的物１１（１．３ｇ）、酢酸アンモニウム（９．７ｇ）、及びエタノール（１００ｍｌ）を、加熱還流下、４時間攪拌した。放冷後、得られた結晶を濾別しメタノール（１００ｍｌ）で洗浄した。乾燥後、目的物１２（０．９８ｇ）を得た。 (ii) Synthesis of target 12

4-Bromo-phenacylpyridinium bromide (3.56 g), target compound 11 (1.3 g), ammonium acetate (9.7 g), and ethanol (100 ml) were stirred with heating under reflux for 4 hours. After allowing to cool, the obtained crystals were separated by filtration and washed with methanol (100 ml). After drying, the desired product 12 (0.98 g) was obtained.

目的物１２（０．９０ｇ）、カルバゾール（０．５３ｇ）、及びナトリウム−ｔｅｒｔ−ブトキシド（０．５６ｇ）にトルエン（３０ｍｌ）を添加し攪拌した。これに、トリス（ジベンジリデンアセトン）ジパラジウム（０）クロロホルム（０．０５ｇ）をトルエン（８ｍｌ）に溶解し、トリ−ｔｅｒｔ−ブチルホスフィン（０．０５５ｇ）を加えた溶液を添加し、加熱還流下、４時間反応させた。放冷後、得られた結晶を濾取し、メタノールで熱懸洗し、メタノール／水混合溶媒で熱懸洗した。さらに、カラムクロマトグラフィーによって精製し、目的物１３（０．６５ｇ）を得た。
ＤＥＩ−ＭＳ（m/z=791(M⁺)）から目的物１３であることを確認した。
このものの融点は３９５℃、気化温度は５５５℃、ガラス転移温度は１６１℃であった。 (iii) Synthesis of target 13

Toluene (30 ml) was added to the target product 12 (0.90 g), carbazole (0.53 g), and sodium-tert-butoxide (0.56 g), and the mixture was stirred. To this, a solution in which tris (dibenzylideneacetone) dipalladium (0) chloroform (0.05 g) was dissolved in toluene (8 ml) and tri-tert-butylphosphine (0.055 g) was added was added and heated to reflux. The reaction was continued for 4 hours. After allowing to cool, the resulting crystals were collected by filtration, washed hot with methanol, and washed hot with a methanol / water mixed solvent. Furthermore, it refine | purified by column chromatography and obtained the target object 13 (0.65g).
From DEI-MS (m / z = 791 (M ⁺ )), it was confirmed to be the target product 13.
This had a melting point of 395 ° C., a vaporization temperature of 555 ° C., and a glass transition temperature of 161 ° C.

３−ブロモベンズアルデヒド（３０．０ｇ）、ジアセチル（６．９８ｇ）、及びピペリジン（０．８０ｍｌ）をエタノール（８０ｍｌ）に溶解し、加熱還流下、２．５時間攪拌した。放冷後、冷蔵庫で冷却し、得られた結晶を濾取、メタノールで洗浄、乾燥し、目的物１４（２．３３ｇ）を得た。 (Synthesis Example 6)
(i) Synthesis of target 14

3-Bromobenzaldehyde (30.0 g), diacetyl (6.98 g), and piperidine (0.80 ml) were dissolved in ethanol (80 ml), and the mixture was stirred for 2.5 hours under heating to reflux. After allowing to cool, the mixture was cooled in a refrigerator, and the resulting crystals were collected by filtration, washed with methanol, and dried to obtain the desired product 14 (2.33 g).

フェナシルピリジニウムブロミド（２．５６ｇ）、目的物１４（２．００ｇ）、酢酸アンモニウム（９．３０ｇ）、及びエタノール（１００ｍｌ）を、加熱還流下、８時間攪拌した。放冷後、得られた結晶を濾取、メタノール（１００ｍｌ）で洗浄後、乾燥し、目的物１５（１．３０ｇ）を得た。 (ii) Synthesis of target 15

Phenacylpyridinium bromide (2.56 g), target compound 14 (2.00 g), ammonium acetate (9.30 g), and ethanol (100 ml) were stirred with heating under reflux for 8 hours. After allowing to cool, the obtained crystals were collected by filtration, washed with methanol (100 ml), and dried to obtain the desired product 15 (1.30 g).

目的物１５（１．２ｇ）、カルバゾール（０．７１ｇ）、及びナトリウム−ｔｅｒｔ−ブトキシド（０．７４ｇ）にトルエン（４０ｍｌ）を添加し攪拌した。これに、トリス（ジベンジリデンアセトン）ジパラジウム（０）クロロホルム（０．０６６ｇ）をトルエン（８ｍｌ）に溶解し、トリ−ｔｅｒｔ−ブチルホスフィン（０．０５１ｇ）を加えた溶液を添加し、加熱還流７時間攪拌した。放冷後、得られた結晶を濾取し、メタノールで熱懸洗し、クロロホルムで熱懸洗を数回繰り返し、昇華精製を行うことにより目的物１６（０．９１ｇ）を得た。
ＤＥＩ−ＭＳ（m/z=791(M⁺)）から目的物１６であることを確認した。
このものの融点は３１６℃、気化温度は３４６℃、ガラス転移温度は１４０℃であった。 (iii) Synthesis of target 16

Toluene (40 ml) was added to the target product 15 (1.2 g), carbazole (0.71 g), and sodium-tert-butoxide (0.74 g), followed by stirring. A solution obtained by dissolving tris (dibenzylideneacetone) dipalladium (0) chloroform (0.066 g) in toluene (8 ml) and adding tri-tert-butylphosphine (0.051 g) was added thereto, followed by heating to reflux. Stir for 7 hours. After allowing to cool, the obtained crystals were collected by filtration, washed with methanol with heat, washed with chloroform several times, and purified by sublimation to obtain the desired product 16 (0.91 g).
From DEI-MS (m / z = 791 (M ⁺ )), it was confirmed to be the target product 16.
This had a melting point of 316 ° C., a vaporization temperature of 346 ° C., and a glass transition temperature of 140 ° C.

３−ブロモフェナシルピリジニウムブロミド（８．２３ｇ）、合成例５で得られた目的物１１（３．００ｇ）、酢酸アンモニウム（２２．５ｇ）、及びエタノール（２００ｍｌ）を、加熱還流下、８時間攪拌した。放冷後、得られた結晶を濾取、メタノールで加熱懸洗、乾燥後、目的物１７（１．０５ｇ）を得た。 (Synthesis Example 7)
(i) Synthesis of target 17

3-Bromophenacylpyridinium bromide (8.23 g), the target compound 11 (3.00 g) obtained in Synthesis Example 5, ammonium acetate (22.5 g), and ethanol (200 ml) were heated under reflux for 8 hours. Stir. After allowing to cool, the obtained crystals were collected by filtration, washed with methanol and washed with heat, and dried to obtain the desired product 17 (1.05 g).

目的物１７（１．４ｇ）、カルバゾール（０．９４ｇ）、及びナトリウム−ｔｅｒｔ−ブトキシド（０．８６ｇ）にトルエン（７０ｍｌ）を添加し攪拌した。これに、トリス（ジベンジリデンアセトン）ジパラジウム（０）クロロホルム（０．０８７ｇ）をトルエン（８ｍｌ）に溶解し、トリ−ｔｅｒｔ−ブチルホスフィン（０．０６８ｇ）を加えた溶液を添加し、加熱還流下、７時間攪拌した。放冷後、得られた結晶を濾別し、メタノールで熱懸洗、クロロホルム熱懸洗を数回繰り返し、昇華精製を行うことにより目的物１８（０．７０ｇ）を得た。
ＤＥＩ−ＭＳ（m/z=791(M⁺)）から目的物１８であることを確認した。
このものの融点は３１７℃、気化温度は５４０℃、ガラス転移温度は１３９℃であった。 (ii) Synthesis of target 18

Toluene (70 ml) was added to the desired product 17 (1.4 g), carbazole (0.94 g), and sodium-tert-butoxide (0.86 g), followed by stirring. A solution in which tris (dibenzylideneacetone) dipalladium (0) chloroform (0.087 g) was dissolved in toluene (8 ml) and tri-tert-butylphosphine (0.068 g) was added thereto was added and heated to reflux. The mixture was stirred for 7 hours. After allowing to cool, the obtained crystal was filtered off, washed with methanol and repeatedly washed with chloroform several times, and purified by sublimation to obtain the target compound 18 (0.70 g).
From DEI-MS (m / z = 791 (M ⁺ )), it was confirmed to be the target compound 18.
This had a melting point of 317 ° C., a vaporization temperature of 540 ° C., and a glass transition temperature of 139 ° C.

窒素気流中、カルバゾール（６．８２ｇ）、４−ブロモヨードベンゼン（１５．０ｇ）、銅粉末（２．６１ｇ）、炭酸カリウム（１１．３ｇ）、及びテトラグライム（３０ｍｌ）を、１４５℃に加熱下、５時間撹拌し、室温まで放冷した。反応混合物にクロロホルムを加え、不溶物を濾別した。濾液に含まれるクロロホルムを減圧留去し、シリカゲルカラムクロマトグラフィー（ｎ−ヘキサン／トルエン＝４／１）で精製した。減圧乾燥することにより、目的物１９（９．０８ｇ、収率６９％）を白色結晶として得た。 (Synthesis Example 8)
(i) Synthesis of target 19

In a nitrogen stream, carbazole (6.82 g), 4-bromoiodobenzene (15.0 g), copper powder (2.61 g), potassium carbonate (11.3 g), and tetraglyme (30 ml) are heated to 145 ° C. The mixture was stirred for 5 hours and allowed to cool to room temperature. Chloroform was added to the reaction mixture, and insoluble matters were filtered off. Chloroform contained in the filtrate was distilled off under reduced pressure and purified by silica gel column chromatography (n-hexane / toluene = 4/1). By drying under reduced pressure, the target product 19 (9.08 g, yield 69%) was obtained as white crystals.

窒素気流中、目的物１９（４．５０ｇ）、ビス（ピナコラートジボロン）（４．６１ｇ）、酢酸カリウム（４．６１ｇ）、及びＤＭＳＯ（７５ｍｌ）を、６０℃に加熱下、１５分間撹拌し、[１，１’−ビス（ジフェニルホスフィノ）フェロセン]ジクロロパラジウム（ＩＩ）ジクロロメタン錯体（０．３４３ｇ）を加え、８０℃に加熱下、６時間撹拌した。室温まで放冷した後、反応液に水（２５０ｍｌ）、及びトルエン（５００ｍｌ）を加え、攪拌した。水層をトルエンで２回再抽出した後、有機層を合わせ、硫酸マグネシウム及び活性白土を加えた。硫酸マグネシウム及び活性白土を濾別し、トルエンを減圧留去した。析出した結晶を冷メタノールで洗浄し、減圧乾燥することにより、目的物２０(４．４６ｇ、収率８６％）を白色結晶として得た。 (ii) Synthesis of target 20

In a nitrogen stream, the target compound 19 (4.50 g), bis (pinacolatodiboron) (4.61 g), potassium acetate (4.61 g), and DMSO (75 ml) were stirred at 60 ° C. for 15 minutes. Then, [1,1′-bis (diphenylphosphino) ferrocene] dichloropalladium (II) dichloromethane complex (0.343 g) was added, and the mixture was stirred at 80 ° C. for 6 hours. After cooling to room temperature, water (250 ml) and toluene (500 ml) were added to the reaction solution and stirred. The aqueous layer was re-extracted twice with toluene, the organic layers were combined, and magnesium sulfate and activated clay were added. Magnesium sulfate and activated clay were separated by filtration, and toluene was distilled off under reduced pressure. The precipitated crystals were washed with cold methanol and dried under reduced pressure to obtain the target product 20 (4.46 g, yield 86%) as white crystals.

合成例７で得られた目的物１７（１．２０ｇ）、目的物２０（１．６４ｇ）、及び炭酸カリウム（１．０７ｇ）に、エチレングリコールジメチルエーテル（８０ｍｌ）、及び水（１６ｍｌ）を添加し攪拌した。これに、テトラキス（トリフェニルフォスフィン）パラジウム（０）（０．１１ｇ）を添加し、加熱還流下、６時間攪拌した。放冷後、濃縮した後、メタノールを添加し、析出物を各種溶媒で洗浄した後、カラムクロマトグラフィーで精製し、目的物２１（１．４０ｇ）を得た。
ＤＥＩ−ＭＳ（m/z=942(M⁺)）から目的物２１であることを確認した。
このものの融点は３６９℃、気化温度は５７４℃、ガラス転移温度は１５５℃であった。 (iii) Synthesis of target product 21

Ethylene glycol dimethyl ether (80 ml) and water (16 ml) were added to the target product 17 (1.20 g), target product 20 (1.64 g) and potassium carbonate (1.07 g) obtained in Synthesis Example 7. Stir. Tetrakis (triphenylphosphine) palladium (0) (0.11 g) was added thereto, and the mixture was stirred for 6 hours while heating under reflux. After allowing to cool and then concentrating, methanol was added, and the precipitate was washed with various solvents and purified by column chromatography to obtain the desired product 21 (1.40 g).
From DEI-MS (m / z = 942 (M ⁺ )), it was confirmed to be the target product 21.
This had a melting point of 369 ° C., a vaporization temperature of 574 ° C., and a glass transition temperature of 155 ° C.

２−アセチルピリジン（９．８０ｇ）、ベンズアルデヒド（８．５７ｇ）、及びピペリジン（０．５ｍｌ）をエタノール（２０ｍｌ）に溶解し、加熱還流下、８時間攪拌した。放冷した後、溶媒を減圧留去し、液体状態として目的物２２（１７．０ｇ）を得た。 (Synthesis Example 9)
(i) Synthesis of target 22

2-acetylpyridine (9.80 g), benzaldehyde (8.57 g), and piperidine (0.5 ml) were dissolved in ethanol (20 ml), and the mixture was stirred for 8 hours under reflux with heating. After allowing to cool, the solvent was distilled off under reduced pressure to obtain the desired product 22 (17.0 g) as a liquid state.

４−ブロモフェナシルピリジニウムブロミド（７．１４ｇ）、目的物２２（８．３６ｇ）、酢酸アンモニウム（３９．０ｇ）、及びエタノール（２００ｍｌ）を、加熱還流下、８時間攪拌して得られた溶液に、メタノール（５０ｍｌ）添加して攪拌し、その後析出した沈殿物を濾過した。得られた結晶をメタノール（２００ｍｌ）で洗浄した。これを濾過して得られた結晶を乾燥し、目的物２３（３．３５ｇ）を得た。 (ii) Synthesis of target 23

A solution obtained by stirring 8-bromophenacylpyridinium bromide (7.14 g), target product 22 (8.36 g), ammonium acetate (39.0 g), and ethanol (200 ml) with heating under reflux for 8 hours. Then, methanol (50 ml) was added and stirred, and then the deposited precipitate was filtered. The obtained crystals were washed with methanol (200 ml). The crystals obtained by filtration were dried to obtain the intended product 23 (3.35 g).

目的物２３（３．００ｇ）、及び２，５−ジフルオロフェニルボロン酸（１．７２ｇ）をエチレングリコールジメチルエーテル（７０ｍｌ）に溶解し、炭酸カリウム３．２２ｇを水１０ｍｌに溶解した水溶液を脱気した後、系内に添加、系内全体を脱気、窒素置換し、加熱攪拌した。これに、内温６０℃で、テトラキス（トリフェニルフォスフィン）パラジウム（０）（０．３６ｇ）を添加後、加熱還流下、４時間攪拌した。放冷後、濃縮し、メタノールで懸洗した後、メタノールにて再結晶後、乾燥して目的物２４（２．４２ｇ）を得た。 (iii) Synthesis of target 24

The target product 23 (3.00 g) and 2,5-difluorophenylboronic acid (1.72 g) were dissolved in ethylene glycol dimethyl ether (70 ml), and an aqueous solution in which 3.22 g of potassium carbonate was dissolved in 10 ml of water was degassed. Thereafter, the mixture was added to the system, the entire system was degassed, purged with nitrogen, and heated and stirred. Tetrakis (triphenylphosphine) palladium (0) (0.36 g) was added thereto at an internal temperature of 60 ° C., and the mixture was stirred for 4 hours while heating under reflux. The mixture was allowed to cool, concentrated, washed with methanol, recrystallized with methanol, and dried to obtain the intended product 24 (2.42 g).

水素化ナトリウム５５％（０．６２ｇ）を脱水ジメチルホルムアミド５０ｍｌに懸濁攪拌し、カルバゾール（２．３８ｇ）を少しづつ系内に添加した。添加終了後、８０℃まで昇温し、目的物２４（１．５ｇ）を添加した。加熱還流下、１２時間攪拌し、放冷後、メタノール（２００ｍｌ）、及び水（４０ｍｌ）に注いだ。得られた結晶を濾取し、メタノールで熱懸洗した後、塩化メチレン／メタノールで再結晶後、カラムクロマトグラフィーで精製し、目的物２５（０．８１ｇ）を得た。
ＤＥＩ−ＭＳ（m/z=714(M⁺)）から目的物２５であることを確認した。
このものの融点は２８２℃、気化温度は５０８℃、ガラス転移温度は１５２℃であった。 (iv) Synthesis of object 25

Sodium hydride 55% (0.62 g) was suspended and stirred in 50 ml of dehydrated dimethylformamide, and carbazole (2.38 g) was gradually added to the system. After completion of the addition, the temperature was raised to 80 ° C., and the target product 24 (1.5 g) was added. The mixture was stirred for 12 hours under reflux with heating, allowed to cool, and then poured into methanol (200 ml) and water (40 ml). The obtained crystals were collected by filtration, washed hot with methanol, recrystallized with methylene chloride / methanol, and purified by column chromatography to obtain the intended product 25 (0.81 g).
From DEI-MS (m / z = 714 (M ⁺ )), it was confirmed to be the intended product 25.
This had a melting point of 282 ° C., a vaporization temperature of 508 ° C., and a glass transition temperature of 152 ° C.

[Example of Organic Electroluminescent Device Production]
Below, the example of preparation of the organic electroluminescent element of this invention is shown.
In the following, a part of the produced organic electroluminescent device was subjected to the following driving life test.

<Driving life test>
Temperature: Room temperature Drive system: DC drive (DC drive)
Initial luminance: 2,500 cd / m ²
Luminance and voltage increase after 1,000 hours from the start of driving were compared. The ratio (L _1,000 / L ₀ ) of the luminance (L _1,000 ) after 1,000 hours to the initial luminance (L ₀ ) and the increase value of the voltage (V _1,000 ) after 1,000 hours from the initial voltage (V ₀ ) ( ΔV = V _1,000 −V ₀ ) was obtained.

Example 1
An organic electroluminescent element having the structure shown in FIG. 3 was produced by the following method.
An indium tin oxide (ITO) transparent conductive film deposited to a thickness of 150 nm on a glass substrate 1 (sputtered film product; sheet resistance 15Ω) is patterned into a 2 mm wide stripe using normal photolithography and hydrochloric acid etching Thus, an anode 2 was formed. The patterned ITO substrate was cleaned in the order of ultrasonic cleaning with acetone, water with pure water, and ultrasonic cleaning with isopropyl alcohol, then dried with nitrogen blow, and finally subjected to ultraviolet ozone cleaning.

  As a material for the hole injection layer 3, a structure shown below is a non-conjugated polymer compound (PB-1 (weight average molecular weight: 29400, number average molecular weight: 12600)) having an aromatic amino group of the structural formula shown below. It spin-coated on the following conditions with the electron-accepting compound (A-2) of a formula.

Spin coating conditions Solvent Ethyl benzoate Coating concentration 2 [wt%]
PB-1: A-2 10: 2 (weight ratio)
Spinner speed 1500 [rpm]
Spinner rotation time 30 [seconds]
Drying conditions 230 [℃] × 15 [min]

  A uniform thin film having a thickness of 30 nm was formed by the above spin coating.

Next, the substrate on which the hole injection layer 3 was formed was placed in a vacuum evaporation apparatus. After roughly exhausting the apparatus with an oil rotary pump, the apparatus was exhausted with a cryopump until the degree of vacuum in the apparatus was 5.2 × 10 ⁻⁵ Pa (about 3.9 × 10 ⁻⁷ Torr) or less. The arylamine compound (H-1) shown below placed in a ceramic crucible arranged in the above apparatus was heated by a tantalum wire heater around the crucible to perform vapor deposition. At this time, the temperature of the crucible was controlled in the range of 258 to 271 ° C. A hole transport layer 4 having a film thickness of 40 nm was obtained at a vacuum degree of 5.8 × 10 ⁻⁵ Pa (about 4.4 × 10 ⁻⁷ Torr) at the time of vapor deposition and at a vapor deposition rate of 0.18 nm / second.

Subsequently, the target product 3 (hereinafter referred to as EM-1) synthesized in Synthesis Example 1 was used as the main component (host material) of the light-emitting layer 5, and the organic iridium complex (D-1) was used as a separate component (dopant) as a separate ceramic. It installed in the crucible and formed into a film by the binary simultaneous vapor deposition method.

The crucible temperature of the target product 3 (EM-1) is 307 to 309 ° C., the deposition rate is controlled to 0.10 nm / second, and the crucible temperature of the compound (D-1) is controlled to 244 to 245 ° C. The light emitting layer 5 containing about 6% by weight of (D-1) was laminated on the hole transport layer 4. The degree of vacuum during the deposition was 5.5 × 10 ⁻⁵ Pa (about 4.1 × 10 ⁻⁷ Torr).

Further, a pyridine derivative (HB-1) shown below was laminated as a hole blocking layer 6 at a crucible temperature of 213 to 216 ° C. with a deposition rate of 0.08 nm / second and a film thickness of 5 nm. The degree of vacuum during the deposition was 4.9 × 10 ⁻⁵ Pa (about 3.7 × 10 ⁻⁷ Torr).

Next, an aluminum 8-hydroxyquinoline complex (ET-1) shown below was deposited as an electron transport layer 7 on the hole blocking layer 6 in the same manner. At this time, the crucible temperature of the aluminum 8-hydroxyquinoline complex is controlled in the range of 250 to 260 ° C., the degree of vacuum during deposition is 5.0 × 10 ⁻⁵ Pa (about 3.8 × 10 ⁻⁷ Torr), and the deposition rate is 0.21. The film thickness was 30 nm at nm / second.

  The substrate temperature at the time of vacuum deposition of the hole injection layer 3, the hole transport layer 4, the light emitting layer 5, the hole blocking layer 6 and the electron transport layer 7 was kept at room temperature.

Here, the element on which the electron transport layer 6 has been deposited is once taken out from the vacuum deposition apparatus into the atmosphere, and a 2 mm wide stripe shadow mask is used as a cathode deposition mask. Installed in a separate vacuum deposition device in close contact with the element at right angles, and the degree of vacuum in the device is 2.0 × 10 ⁻⁶ Torr (about 2.7 × 10 ⁻⁴ Pa) or less in the same manner as the organic layer Was exhausted. As the cathode 8, first, lithium fluoride (LiF) is deposited on a molybdenum boat at a deposition rate of 0.03 nm / second, a vacuum degree of 2.8 × 10 ⁻⁶ Torr (about 3.7 × 10 ⁻⁴ Pa), and a film thickness of 0.5 nm. Then, a film was formed on the electron transport layer 7. Next, aluminum was similarly heated by a molybdenum boat to form an aluminum layer with a thickness of 80 nm at a deposition rate of 0.46 nm / second and a degree of vacuum of 9.6 × 10 ⁻⁶ Torr (about 1.3 × 10 ⁻³ Pa) to form a cathode. 8 was completed. The substrate temperature at the time of vapor deposition of the above two-layer cathode 8 was kept at room temperature.

As described above, an organic electroluminescent element having a light emitting area portion having a size of 2 mm × 2 mm was obtained.
The light emission characteristics and lifetime characteristics of this element are shown in Table 1.
The maximum wavelength of the emission spectrum of the device was 512 nm, and the chromaticity was CIE (x, y) = (0.30, 0.60), which was identified as that from the organic iridium complex (D-1).
This device had higher luminous efficiency and a longer life compared to the device of Comparative Example described later.

(Example 2)
A device was fabricated in the same manner as in Example 1 except that the pyridine derivative (HB-1) of the hole blocking layer was not laminated.
The light emission characteristics and lifetime characteristics of this element are shown in Table 1.
The maximum wavelength of the emission spectrum of the device was 512 nm, and the chromaticity was CIE (x, y) = (0.29, 0.60), which was identified as that from the organic iridium complex (D-1).
In this device, light emission from the organic iridium complex was obtained with high efficiency even without the hole blocking layer.

(Example 3)
A device was fabricated in the same manner as in Example 1 except that the target product 5 (hereinafter referred to as EM-2) shown below was used instead of the target product 3 (EM-1) as the main component (host material) of the light emitting layer 5. did.
The light emission characteristics of this device are shown in Table 1.
The maximum wavelength of the emission spectrum of the device was 514 nm, and the chromaticity was CIE (x, y) = (0.30, 0.61), which was identified as that from the organic iridium complex (D-1).
In this element, light emission from the organic iridium complex was obtained with high efficiency, and the driving voltage was low.

Example 4
A device was produced in the same manner as in Example 3 except that the pyridine derivative (HB-1) of the hole blocking layer was not laminated.
The light emission characteristics of this device are shown in Table 1.
The maximum wavelength of the emission spectrum of the device was 514 nm, and the chromaticity was CIE (x, y) = (0.30, 0.61), which was identified as that from the organic iridium complex (D-1).
In this device, light emission from the organic iridium complex was obtained with high efficiency even without the hole blocking layer, and the driving voltage was low.

(Example 5)
A device was fabricated in the same manner as in Example 1 except that the target 7 (EM-3) shown below was used instead of the target 3 (EM-1) as the main component (host material) of the light emitting layer 5. did.
The light emission characteristics of this device are shown in Table 1.
The maximum wavelength of the emission spectrum of the device was 513 nm, and the chromaticity was CIE (x, y) = (0.30, 0.61), which was identified as that from the organic iridium complex (D-1).

(Example 6)
A device was fabricated in the same manner as in Example 5 except that the pyridine derivative (HB-1) of the hole blocking layer was not laminated.
The light emission characteristics of this device are shown in Table 1.
The maximum wavelength of the emission spectrum of the device was 513 nm, and the chromaticity was CIE (x, y) = (0.30, 0.61), which was identified as that from the organic iridium complex (D-1).
In this device, light emission from the organic iridium complex was obtained with high efficiency even without the hole blocking layer, and the driving voltage was lower than in Comparative Example 1 and Comparative Example 2.

(Example 7)
A device was fabricated in the same manner as in Example 2, except that the target 16 (EM-4) shown below was used as the main component (host material) of the light emitting layer 5 instead of the target 3 (EM-1).
The light emission characteristics of this device are shown in Table 1.
The maximum wavelength of the emission spectrum of the device was 513 nm, and the chromaticity was CIE (x, y) = (0.30, 0.61), which was identified as that from the organic iridium complex (D-1).
In this device, light emission from the organic iridium complex was obtained with high efficiency without the hole blocking layer, and the voltage was lower than that of Comparative Example 2.

(Example 8)
A device was fabricated in the same manner as in Example 2 except that the target product 21 (EM-5) shown below was used as the main component (host material) of the light-emitting layer 5 instead of the target product 3 (EM-1).
The light emission characteristics of this device are shown in Table 1.
The maximum wavelength of the emission spectrum of the device was 513 nm, and the chromaticity was CIE (x, y) = (0.30, 0.61), which was identified as that from the organic iridium complex (D-1).
In this device, light emission from the organic iridium complex was obtained with high efficiency without the hole blocking layer, and the voltage was lower than that of Comparative Example 2.

Example 9
A device was fabricated in the same manner as in Example 1 except that the target 25 (EM-6) shown below was used instead of the target 3 (EM-1) as the main component (host material) of the light emitting layer 5.
The light emission characteristics of this device are shown in Table 1.
The maximum wavelength of the emission spectrum of the device was 514 nm, and the chromaticity was CIE (x, y) = (0.31,0.61), which was identified as that from the organic iridium complex (D-1).
In this device, light emission from the organic iridium complex was obtained with high efficiency, and the voltage was lower than that of Comparative Example 1.

(Example 10)
A device was fabricated in the same manner as in Example 9 except that the hole blocking layer pyridine derivative (HB-1) was not laminated.
The light emission characteristics of this device are shown in Table 1.
The maximum wavelength of the emission spectrum of the device was 515 nm, and the chromaticity was CIE (x, y) = (0.31,0.62), which was identified as that from the organic iridium complex (D-1).
In this device, light emission from the organic iridium complex was obtained with high efficiency even without the hole blocking layer, and the voltage was lower than that of Comparative Example 2.

(Comparative Example 1)
A device was fabricated in the same manner as in Example 1 except that (CBP) shown below was used as the main component (host material) of the light emitting layer 5 instead of the target (EM-1).
The light emission characteristics and lifetime characteristics of this element are shown in Table 1.
The maximum wavelength of the emission spectrum of the device was 514 nm, and the chromaticity was CIE (x, y) = (0.30,0.58), which was identified as that from the organic iridium complex (D-1).
This device had lower luminous efficiency than the devices of Examples 1-6.

(Comparative Example 2)
A device was prepared in the same manner as in Comparative Example 1 except that the pyridine derivative (HB-1) of the hole blocking layer was not laminated.
The light emission characteristics of this device are shown in Table 1.
The maximum wavelength of the emission spectrum of the device was 512 nm, and the chromaticity was CIE (x, y) = (0.30, 0.60), which was identified as that from the organic iridium complex (D-1).
In this device, light emission from the organic iridium complex was obtained even without the hole blocking layer, but the light emission efficiency was low as compared with the devices of Examples 1-6. Also, the drive voltage was higher than that of the devices of Examples 1 and 2.

  As described above, the elements of Examples 1 to 4 have higher luminous efficiency than the elements of Comparative Examples 1 and 2, and in particular, the elements of Examples 1 and 2 are compared with the elements of Comparative Example 1. The brightness is high and the voltage rise is small. From these results, it is clear that by using the organic compound of the present invention, a long-lived phosphorescent device having high efficiency and excellent driving stability is realized.

It is typical sectional drawing which showed an example of the organic electroluminescent element of this invention. It is typical sectional drawing which showed another example of the organic electroluminescent element of this invention. It is typical sectional drawing which showed another example of the organic electroluminescent element of this invention.

Explanation of symbols

1 substrate 2 anode 3 hole injection layer (anode buffer layer)
4 hole transport layer 5 light emitting layer 6 hole blocking layer 7 electron transport layer 8 cathode

Claims (7)

An organic compound represented by the following formula (I), wherein the following formula (I ′), which is a partial structure of the following formula (I), is represented by the following formula (III-1): Compound.

(In the formula, Cz ¹ and Cz ² represent a carbazolyl group. Cz ¹ and Cz ² may be the same or different.
Q ¹ and Q ² represent a direct bond or a linking group selected from the following (1). Q ¹ and Q ² may be the same or different.
Cz ¹ , Cz ² , Q ¹ , Q ² , Ring B ¹ and Ring B ² may each have a substituent selected from the following (2). )
(1) Benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, perylene ring, tetracene ring, pyrene ring, benzpyrene ring, chrysene ring, triphenylene ring, fluoranthene ring, 6-membered monocyclic ring or 2-5 condensed ring Or a divalent linking group formed by linking a plurality of them (2) alkyl group, aromatic hydrocarbon group, acyl group, alkoxy group, aryloxy group, alkylthio group, arylthio group Group, alkoxycarbonyl group, aryloxycarbonyl group, halogen atom, arylamino group, alkylamino group, aromatic heterocyclic group

(In the formula, ring B ¹ and ring B ² have the same meanings as in formula (I).) The organic compound according to claim 1, wherein the formula (I) is the following formula (I-1).

(In the formula, G ^{1 to} G ⁴ represent a direct bond or a linking group selected from the following (1). G ^{1 to} G ⁴ may be the same or different.
Ring A ¹ and ring A ² are each a benzene ring which may have a substituent selected from the following (2).
Cz ¹ , Cz ² , ring B ¹ and ring B ² are as defined in formula (I). )
(1) Benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, perylene ring, tetracene ring, pyrene ring, benzpyrene ring, chrysene ring, triphenylene ring, fluoranthene ring, 6-membered monocyclic ring or 2-5 condensed ring Or a divalent linking group formed by linking a plurality of them (2) alkyl group, aromatic hydrocarbon group, acyl group, alkoxy group, aryloxy group, alkylthio group, arylthio group Group, alkoxycarbonyl group, aryloxycarbonyl group, halogen atom, arylamino group, alkylamino group, aromatic heterocyclic group The organic compound according to claim 1, wherein the formula (I) is the following formula (I-2).

(In the formula, G ⁵ represents a direct bond or a linking group selected from the following (1).
Z represents a linking group selected from the following (1) capable of conjugating nitrogen atoms on Cz ¹ and Cz ² . Z may have a substituent selected from the following (2).
Cz ¹ , Cz ² , ring B ¹ and ring B ² are as defined in formula (I). )
(1) Benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, perylene ring, tetracene ring, pyrene ring, benzpyrene ring, chrysene ring, triphenylene ring, fluoranthene ring, 6-membered monocyclic ring or 2-5 condensed ring Or a divalent linking group formed by linking a plurality of them (2) alkyl group, aromatic hydrocarbon group, acyl group, alkoxy group, aryloxy group, alkylthio group, arylthio group Group, alkoxycarbonyl group, aryloxycarbonyl group, halogen atom, arylamino group, alkylamino group, aromatic heterocyclic group The organic compound according to claim 1, wherein the formula (I) is the following formula (I-3).

(In the formula, Cz ¹ , Cz ² , Q ¹ , Q ² , ring B ¹ and ring B ² have the same meanings as in formula (I).) The organic compound according to any one of claims 1 to 4 , wherein all carbazolyl groups present in the molecule are N-carbazolyl groups represented by the following formula (II).

A charge transport material comprising the organic compound according to any one of claims 1 to 5 . The organic electroluminescent device having an anode, a cathode, and an organic light emitting layer provided between both electrodes on a substrate, wherein the organic material according to any one of claims 1 to 5 is interposed between the anode and the cathode. An organic electroluminescent device comprising a layer containing a compound.

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