JP2006213686A - Metal complex compound and organic electroluminescent device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic electroluminescent device high in emission efficiency and having long service life, and to provide a new metal complex compound realizing the device. <P>SOLUTION: The new metal complex compound of a specific structure containing a metal atom such as iridium is provided. The organic electroluminescent device is such that a single or multiple organic thin film layers including at least luminescent layer are sandwiched in between a pair of electrodes, wherein at least one layer of the organic thin film layers contains the metal complex compound. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a metal complex compound and an organic electroluminescence device using the same, and more particularly to an organic electroluminescence device having high luminous efficiency and a long lifetime and a novel metal complex compound that realizes the organic electroluminescence device.

An organic electroluminescence (EL) element is a self-luminous element utilizing the principle that a fluorescent substance emits light by recombination energy of holes injected from an anode and electrons injected from a cathode by applying an electric field. . Eastman Kodak's C.I. W. Tang et al. Have reported a low-voltage driven organic EL element using a stacked element (CW Tang, SA Vanslyke, Applied Physics Letters, 51, 913, 1987, etc.). Since then, researches on organic EL elements using organic materials as constituent materials have been actively conducted. Tang et al. Use tris (8-quinolinolato) aluminum for the light emitting layer and a triphenyldiamine derivative for the hole transporting layer. The advantages of the stacked structure are that it increases the efficiency of hole injection into the light-emitting layer, blocks the electrons injected from the cathode, increases the generation efficiency of excitons generated by recombination, and generates in the light-emitting layer For example, confining excitons. As in this example, the element structure of the organic EL element includes a hole transport (injection) layer, a two-layer type of an electron transport light emitting layer, or a hole transport (injection) layer, a light emitting layer, and an electron transport (injection) layer. A three-layer type is well known. In such a stacked structure element, the element structure and the formation method are devised in order to increase the recombination efficiency of injected holes and electrons.
As light-emitting materials for organic EL elements, chelate complexes such as tris (8-quinolinolato) aluminum complex, light-emitting materials such as coumarin derivatives, tetraphenylbutadiene derivatives, distyrylarylene derivatives, oxadiazole derivatives, and the like are known. It is reported that light emission in the visible region from blue to red can be obtained, and realization of a color display element is expected (see, for example, Patent Document 1, Patent Document 2, Patent Document 3, etc.).

In recent years, it has been proposed to use a phosphorescent material in addition to a fluorescent material for the light emitting layer of an organic EL element (see, for example, Non-Patent Document 1 and Non-Patent Document 2). Thus, high emission efficiency is achieved by utilizing the singlet state and triplet state of the phosphorescent material in the light emitting layer of the organic EL element. When electrons and holes are recombined in an organic EL device, it is considered that singlet excitons and triplet excitons are generated at a ratio of 1: 3 due to the difference in spin multiplicity. If the light emitting material is used, it is conceivable that the light emission efficiency is 3 to 4 times that of an element using only fluorescence.
In such an organic EL element, an anode, a hole transport layer, an organic light emitting layer, an electron transport layer (a hole blocking layer) are sequentially arranged so that a triplet excited state or a triplet exciton is not quenched. A structure in which layers are stacked such as an electron transport layer and a cathode has been used, and a host compound and a phosphorescent compound have been used for an organic light emitting layer (see, for example, Patent Document 4 and Patent Document 5). These patent documents are technologies related to phosphorescent materials that emit red to green light. Moreover, the technique regarding the luminescent material which has a blue luminescent color is also released (for example, refer patent document 6, patent document 7, patent document 8). However, they have a very short element lifetime, and in particular, Patent Documents 7 and 8 describe a ligand skeleton in which an Ir metal and a phosphorus atom are bonded. Although the emission color is blue, the bond is weak and heat-resistant. Sexually poor. Similarly, Patent Document 9 describes a complex in which an oxygen atom and a nitrogen atom are bonded to the central metal, but there is no description about the specific effect of the group bonded to the oxygen atom, and it is unclear. Furthermore, Patent Document 10 discloses a complex in which nitrogen atoms contained in different ring structures are bonded to a central metal one by one, and an element using the same emits blue light, but the external quantum efficiency is around 5%. It is low. Further, Patent Document 11 discloses a complex in which substituents CF ₃ and F are introduced on a carbon atom adjacent to a carbon atom forming a metal-carbon bond of a phenylpyridine ligand as a metal example of an Ir complex. . However, no specific effect on the bluening of this position is described.

JP-A-8-239655 Japanese Patent Laid-Open No. 7-183561 JP-A-3-200289 US Pat. No. 6,097,147 International Publication WO01 / 41512 US2001 / 0025108 Publication US2002 / 0182441 Publication JP 2002-170684 A JP 2003-123982 A JP 2003-133074 A US2003 / 0040627 D. F. OBrien, M.M. A. Baldo et al. "Improved energy transfer electrophorescentive devices", Vol. 74, no. 3, pp. 442-444, January 18, 1999. M.M. A. Baldo et al. , “Very high-efficiency green organic light-emitting devices based on electrophoretics”, Applied Physics Letters, Vol. 75, no. 1, pp. 4-6, July 5, 1999.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an organic EL device having high luminous efficiency and a long lifetime and a novel metal complex compound that realizes the organic EL device.

  As a result of intensive studies to achieve the above object, the present inventors have obtained an organic EL device with high luminous efficiency and long life when a metal complex compound represented by the following general formula (1) is used. As a result, the present invention has been completed.

｛一般式（２）及び（３）において、Ｎは、窒素原子であり、Ｑは窒素原子又は炭素原子を表す。Ａ環は、置換基を有してもよい核炭素数４〜４０のアリール基又はシクロアルケニル基であり、Ｂ環は、置換基を有してもよい窒素原子を含有する核原子数３〜４０の芳香族複素環基であり、Ａ環とＢ環は炭素又は窒素原子を介して共有結合により結合している。Ｒ₁及びＲ₄は、それぞれ独立に、置換基を有してもよい炭素数１〜３０のアルキル基、置換基を有してもよい炭素数２〜３０のハロゲン化アルキル基、置換基を有してもよい核原子数３〜３０の芳香族複素環基、置換基を有してもよい核炭素数６〜３０のアリール基、置換基を有してもよい炭素数７〜４０のアラルキル基、置換基を有してもよい炭素数２〜３０のアルケニル基、置換基を有してもよい炭素数６〜４０のアリールアミノ基、置換基を有してもよい炭素数１〜４０のアルキルアミノ基、置換基を有してもよい炭素数３〜３０アルキルシリル基、置換基を有してもよい炭素数６〜３０のアリールシリル基、チオシアノ基、シアノ基、ニトロ基、−Ｓ（Ｒ）Ｏ₂基、−Ｓ（Ｒ）Ｏ（Ｒは置換基）、置換基を有してもよい炭素数１〜３０のアルコキシ基又は置換基を有してもよい炭素数１〜３０のエステル基、塩素原子、臭素原子及びヨウ素原子から選ばれる。Ｒ₂は、上記Ｒ₁及びＲ₄と同じ基、水素原子、フッ素原子及びトリフルオロメチル基から選ばれる。Ｒ₃は、それぞれ独立に、置換基を有してもよい炭素数１〜３０のアルキル基、置換基を有してもよい炭素数２〜３０のハロゲン化アルキル基、置換基を有してもよい核原子数３〜３０の芳香族複素環基、置換基を有してもよい核炭素数６〜３０のアリール基、置換基を有してもよい炭素数７〜４０のアラルキル基、置換基を有してもよい炭素数２〜３０のアルケニル基、置換基を有してもよい炭素数６〜４０のアリールアミノ基、置換基を有してもよい炭素数１〜４０のアルキルアミノ基、置換基を有してもよい炭素数３〜３０アルキルシリル基、置換基を有してもよい炭素数６〜３０のアリールシリル基、チオシアノ基、シアノ基、ニトロ基、−Ｓ（Ｒ）Ｏ₂基、−Ｓ（Ｒ）Ｏ（Ｒは置換基）、置換基を有してもよい炭素数１〜３０のアルコキシ基又は置換基を有してもよい炭素数１〜３０のエステル基及び水素原子から選ばれる。Ｒ₂とＲ₃は互いに結合して、環状構造を形成してもよい。Ｒ₁及びＲ₄はそれぞれＭと結合する炭素原子の隣の炭素原子に結合する。｝］ The present invention provides the following metal complex compounds (a) to (j) and organic electroluminescence devices (k) to (o) using the same. That is, the present invention provides (a) a metal complex compound represented by the following general formula (1),
(L ₁ ) _m M (L ₂ ) _n (1)
[In General Formula (1), M is a metal atom of iridium (Ir), platinum (Pt), rhodium (Rh) or palladium (Pd), and L ₁ and L ₂ are bidentate ligands different from each other. is there. m is an integer of 1 to 3, n is an integer of 0 to 1, and m + n is an integer of 2 or 3.
The partial structure (L ₁ ) _m M is represented by the following general formula (2) or (3).

{In General Formulas (2) and (3), N represents a nitrogen atom, and Q represents a nitrogen atom or a carbon atom. The A ring is an aryl group or cycloalkenyl group having 4 to 40 nuclear carbon atoms which may have a substituent, and the B ring has 3 to 3 nuclear atoms containing a nitrogen atom which may have a substituent. 40 aromatic heterocyclic groups, the A ring and the B ring are bonded by a covalent bond via a carbon or nitrogen atom. R ₁ and R ₄ are each independently an alkyl group having 1 to 30 carbon atoms which may have a substituent, a halogenated alkyl group having 2 to 30 carbon atoms which may have a substituent, or a substituent. An aromatic heterocyclic group having 3 to 30 nuclear atoms, an aryl group having 6 to 30 nuclear carbon atoms which may have a substituent, and an alkyl group having 7 to 40 carbon atoms which may have a substituent An aralkyl group, an optionally substituted alkenyl group having 2 to 30 carbon atoms, an optionally substituted arylamino group having 6 to 40 carbon atoms, and an optionally substituted carbon atom having 1 to 1 carbon atoms 40 alkylamino groups, an optionally substituted alkyl silyl group having 3 to 30 carbon atoms, an optionally substituted aryl silyl group having 6 to 30 carbon atoms, a thiocyano group, a cyano group, a nitro group, -S (R) O ₂ group, -S (R) O (R is a substituted group), carbon atoms which may have a substituent group 1-3 Alkoxy group or a substituent a good ester group having 1 to 30 carbon atoms which may have a chlorine atom, selected from bromine and iodine atoms. R ₂ is selected from the same group as the above R ₁ and R ₄ , a hydrogen atom, a fluorine atom and a trifluoromethyl group. R ₃ each independently has an optionally substituted alkyl group having 1 to 30 carbon atoms, an optionally substituted halogenated alkyl group having 2 to 30 carbon atoms, and a substituent. An aromatic heterocyclic group having 3 to 30 nuclear atoms, an aryl group having 6 to 30 nuclear carbon atoms which may have a substituent, an aralkyl group having 7 to 40 carbon atoms which may have a substituent, An optionally substituted alkenyl group having 2 to 30 carbon atoms, an optionally substituted arylamino group having 6 to 40 carbon atoms, and an optionally substituted alkyl having 1 to 40 carbon atoms An amino group, an optionally substituted alkyl silyl group having 3 to 30 carbon atoms, an optionally substituted aryl silyl group having 6 to 30 carbon atoms, a thiocyano group, a cyano group, a nitro group, -S ( R) O ₂ group, —S (R) O (R is a substituent), and optionally having 1 to 30 carbon atoms. It is selected from a C1-30 ester group which may have a alkoxy group or a substituent and a hydrogen atom. R ₂ and R ₃ may be bonded to each other to form a cyclic structure. R ₁ and R ₄ are each bonded to a carbon atom adjacent to the carbon atom bonded to M. }]

（式中、Ｍ及びｍはそれぞれ前記と同じである。Ｒ₅、Ｒ₁₀及びＲ₁₄は、それぞれ独立に、一般式（２）及び（３）におけるＲ₁及びＲ₄と同じ基から選ばれる。Ｒ₆〜Ｒ₉、Ｒ₁₁〜Ｒ₁₃、Ｒ₁₅及びＲ₁₇は、それぞれ独立に、一般式（２）におけるＲ₂と同じ基から選ばれる。Ｒ₁₆は、一般式（２）におけるＲ₃と同じ基から選ばれる。Ｒ₆とＲ₇、Ｒ₇とＲ₈、Ｒ₈とＲ₉、Ｒ₁₁とＲ₁₂、Ｒ₁₂とＲ₁₃、Ｒ₁₅とＲ₁₆及びＲ₁₆とＲ₁₇はそれぞれ互いに結合して、環状構造を形成してもよい。Ｒ₅、Ｒ₁₀及びＲ₁₄はそれぞれＭと結合する炭素原子の隣の炭素原子に結合する。） (B) the metal complex compound of (a) in which the partial structure (L ₁ ) _m M in the general formula (1) is represented by any one of the following general formulas (4) to (6),

(In the formula, M and m are the same as defined above. R ₅ , R ₁₀ and R ₁₄ are each independently selected from the same groups as R ₁ and R ₄ in formulas (2) and (3)). R _{6 to} R ₉ , R _{11 to} R ₁₃ , R ₁₅ and R ₁₇ are each independently selected from the same group as R ₂ in the general formula (2), and R ₁₆ is R in the general formula (2). R ₆ and R ₇ , R ₇ and R ₈ , R ₈ and R ₉ , R ₁₁ and R ₁₂ , R ₁₂ and R ₁₃ , R ₁₅ and R _16, and R ₁₆ and R ₁₇ are selected from the same groups as _3. Each may be bonded to each other to form a cyclic structure, and R ₅ , R ₁₀ and R ₁₄ are each bonded to the carbon atom adjacent to the carbon atom bonded to M.)

（式中、Ｍ及びｍはそれぞれ前記と同じである。Ｒ₁₈、Ｒ₂₅、Ｒ₃₁は、それぞれ独立に、一般式（２）及び（３）におけるＲ₁及びＲ₄と同じ基から選ばれる。Ｒ₁₉〜Ｒ₂₄、Ｒ₂₆〜Ｒ₃₀、Ｒ₃₂〜Ｒ₃₄及びＲ₃₆は、それぞれ独立に、一般式（２）におけるＲ₂と同じ基から選ばれる。Ｒ₃₅は、一般式（２）におけるＲ₃と同じ基から選ばれる。Ｒ₂₀とＲ₂₁、Ｒ₂₁とＲ₂₂、Ｒ₂₂とＲ₂₃、Ｒ₂₃とＲ₂₄、Ｒ₂₇とＲ₂₈、Ｒ₂₈とＲ₂₉、Ｒ₂₉とＲ₃₀、Ｒ₃₃とＲ₃₄、Ｒ₃₄とＲ₃₅及びＲ₃₅とＲ₃₆はそれぞれ互いに結合して、環状構造を形成してもよい。Ｒ₁₈、Ｒ₂₅及びＲ₃₁はそれぞれＭと結合する炭素原子の隣の炭素原子に結合する。） (C) the metal complex compound of (a), wherein the partial structure (L ₁ ) _m M in the general formula (1) is a partial structure represented by any one of the following general formulas (7) to (9),

(In the formula, M and m are the same as defined above. R ₁₈ , R ₂₅ and R ₃₁ are each independently selected from the same groups as R ₁ and R ₄ in formulas (2) and (3)). _{.R 19 ~R 24, R 26 ~R} 30, R 32 ~R 34 and R ₃₆ are each independently, .R ₃₅ selected from the same group as R ₂ in the general formula (2) has the general formula (2 ) and .R ₂₀ and R _21, R ₂₁ and R _22, R ₂₂ and R _23, R ₂₃ and R _24, R ₂₇ and R _28, R ₂₈ and R _29, R ₂₉ selected from the same group as R ₃ in R ₃₀ , R ₃₃ and R ₃₄ , R ₃₄ and R ₃₅ and R ₃₅ and R ₃₆ may be bonded to each other to form a cyclic structure, and R ₁₈ , R ₂₅ and R ₃₁ are each bonded to M. Bonds to the carbon atom next to the carbon atom.)

(式中、Ｍ、ｍ、Ｎ、Ｑ、Ａ環及びＢ環はいずれも一般式（２）及び（３）におけるものと同じである。Ｒ_1'及びＲ_4'は、それぞれ独立に、一般式（２）及び（３）におけるＲ₁及びＲ₄と同じ基及びハロゲン原子から選ばれる。Ｒ_2'は、一般式（２）におけるＲ₂と同じ基から選ばれる。Ｒ_3'は、一般式（２）におけるＲ₃と同じ基から選ばれる。Ｒ₅₉及びＲ₆₀は、それぞれ独立に、一般式（２）及び（３）におけるＲ₁及びＲ₄と同じ基、フッ素原子及びトリフルオロメチル基から選ばれる。Ｒ₅₉及びＲ₆₀はそれぞれＲ_1'とＲ_4'に結合する炭素原子の隣の炭素原子に結合する) (D) the metal complex compound of (a) in which the partial structure (L ₁ ) _m M in the general formula (1) is represented by the following general formula (10) or (11),

(In the formula, all of M, m, N, Q, A ring and B ring are the same as those in formulas (2) and (3). R _{1 ′} and R _{4 ′} are each independently equation (2) and (3) .R 2 selected from the same group and a halogen atom and R ₁ and R ₄ in _'is .R 3 which selected from the same group as R ₂ in the general formula _(2)' is generally .R ₅₉ and R ₆₀ are selected from the same group as R ₃ in formula (2) are each independently a general formula (2) and the same group as R ₁ and R ₄ in (3), a fluorine atom and trifluoromethyl R ₅₉ and R ₆₀ are each bonded to the carbon atom adjacent to the carbon atom bonded to R _{1 ′} and R _{4 ′} )

（式中、Ｍ及びｍはそれぞれ前記と同じである。Ｒ_5'、Ｒ_10'及びＲ_14'は、それぞれ独立に、一般式（２）及び（３）におけるＲ₁及びＲ₄と同じ基から選ばれる。Ｒ_6'〜Ｒ_9'、Ｒ_11'〜Ｒ_13'、Ｒ_15'及びＲ_17'は、それぞれ独立に、一般式（２）におけるＲ₂と同じ基から選ばれる。Ｒ_16'は、一般式（２）におけるＲ₃と同じ基から選ばれる。Ｒ₆₁〜Ｒ₆₃は、一般式（１０）及び（１１）におけるＲ₅₉及びＲ₆₀と同じ基から選ばれる。Ｒ_6'とＲ_7'、Ｒ_7'とＲ_8'、Ｒ_8'とＲ_9'、Ｒ_11'とＲ_12'、Ｒ_12'とＲ_13'、Ｒ_15'とＲ_16'及びＲ_16'とＲ_17'はそれぞれ互いに結合して、環状構造を形成してもよい。Ｒ_5'、Ｒ_10'及びＲ_14'はそれぞれＭと結合する炭素原子の隣の炭素原子に結合する。） (E) the metal complex compound (d) in which the partial structure (L ₁ ) _m M in the general formula (1) is represented by any one of the following general formulas (12) to (14),

(In the formula, M and m are the same as defined above. R _{5 ′} , R _{10 ′} and R _{14 ′} are each independently the same groups as R ₁ and R ₄ in the general formulas (2) and (3)). selected from _{.R 6 '~R 9', R} 11 '~R 13', .R R 15 ' and R _17' are each independently selected from the same group as R ₂ in the general formula (2) _{16 'is} .R ₆₁ to R ₆₃ is selected from the same group as R ₃ in the general formula (2) has the general formula (10) and (11) .R ₆ selected from the same group as R ₅₉ and R _60' in And R _{7 ′} , R _{7 ′} and R _{8 ′} , R _{8 ′} and R _{9 ′} , R _{11 ′} and R _{12 ′} , R _{12 ′} and R _{13 ′} , R _{15 ′} and R _{16 ′} and R _{16 ′} and R _{17 ′} may be bonded to each other to form a cyclic structure. R _{5 ′} , R _{10 ′} and R _{14 ′} are each bonded to the carbon atom adjacent to the carbon atom bonded to M.)

（式中、Ｍ及びｍはそれぞれ前記と同じである。Ｒ_18'、Ｒ_25'及びＲ_31'は、それぞれ独立に、一般式（２）及び（３）におけるＲ₁及びＲ₄と同じ基から選ばれる。Ｒ_20'〜Ｒ_24'、Ｒ_27'〜Ｒ_30'、Ｒ_33'、Ｒ_34'及びＲ_36'は、それぞれ独立に、一般式（２）におけるＲ₂と同じ基から選ばれる。Ｒ_35'は、一般式（２）におけるＲ₃と同じ基から選ばれる。Ｒ_19`、Ｒ_26'及びＲ_32'は、それぞれ独立に、一般式（１０）及び（１１）におけるＲ₅₉及びＲ₆₀と同じ基から選ばれる。Ｒ_20'とＲ_21'、Ｒ_21'とＲ_22'、Ｒ_22'とＲ_23'、Ｒ_23'とＲ_24'、Ｒ_27'とＲ_28'、Ｒ_28'とＲ_29'、Ｒ_29'とＲ_30'、Ｒ_33'とＲ_34'、Ｒ_34'とＲ_35'及びＲ_35'とＲ_36'はそれぞれ互いに結合して、環状構造を形成してもよい。Ｒ_18'、Ｒ_25'及びＲ_31'はそれぞれＭと結合する炭素原子の隣の炭素原子に結合する。） (F) The metal complex compound of (d), wherein the partial structure (L ₁ ) _m M in the general formula (1) is a partial structure represented by any of the following general formulas (15) to (17),

Wherein M and m are the same as defined above. R _{18 ′} , R _{25 ′} and R _{31 ′} are each independently the same group as R ₁ and R ₄ in the general formulas (2) and (3). R _{20 ′ to} R _{24 ′} , R _{27 ′ to} R _{30 ′} , R _{33 ′} , R _{34 ′} and R _{36 ′} are each independently selected from the same groups as R ₂ in the general formula (2) R _{35 ′} is selected from the same group as R ₃ in the general formula (2) R _{19 ′} , R _{26 ′} and R _{32 ′} are each independently R in the general formulas (10) and (11). ₅₉ and R ₆₀ are selected from the same group: R _{20 ′} and R _{21 ′} , R _{21 ′} and R _{22 ′} , R _{22 ′} and R _{23 ′} , R _{23 ′} and R _{24 ′} , R _{27 ′} and R _{28 ′.} , R _{28 ′} and R _{29 ′} , R _{29 ′} and R _{30 ′} , R _{33 ′} and R _{34 ′} , R _{34 ′} and R _{35 ′} and R _{35 ′} and R _{36 ′} are bonded to each other to form a cyclic structure. R _{18 ′} , R _{25 ′} and R _{31 ′} may each be a carbon atom bonded to M. To the next carbon atom.)

（式中、Ｍ及びｎはそれぞれ前記と同じである。Ｒ₃₇〜Ｒ₅₈は、それぞれ独立に、一般式（２）におけるＲ₂と同じ基から選ばれる。Ｒ₃₇〜Ｒ₅₈のうち隣り合うものはそれぞれ互いに結合して、環状構造を形成してもよい。） (G) The metal complex compound of (a) in which the partial structure M (L ₂ ) _n in the general formula (1) is represented by any of the following general formulas (18) to (22),

(In the formula, M and n are the same as defined above. R _{37 to} R ₅₈ are each independently selected from the same groups as R ₂ in formula (2). Adjacent of R _{37 to} R _58. Each may be bonded together to form a ring structure.)

(H) The metal complex compound of any one of (a) to (f), wherein m = 3, n = 0 and M is Ir in the general formula (1),
(I) The metal complex compound of any one of (a) to (g), wherein m = 2, n = 1 and M is Ir in the general formula (1),
(J) The metal complex compound of any one of (a) to (f), wherein m = 2, n = 0 and M is Pt in the general formula (1),
(K) In the general formula (1), L ₁ is a bidentate ligand of any one of the general formulas (15) to (17), and L ₂ is a bidentate ligand of the general formula (18) The metal complex compound of (a), wherein M is Ir, m and n are integers of 1 to 2, and m + n = 3,
(L) In the general formula (1), L ₁ is a bidentate ligand of any one of the general formulas (15) to (17), and L ₂ is a bidentate ligand of the general formula (19) The metal complex compound of (a), wherein M is Ir, m and n are integers of 1 to 2, and m + n = 3,
(M) In the general formula (1), L ₁ is a bidentate ligand of any one of the general formulas (15) to (17), and L ₂ is a bidentate ligand of the general formula (20). The metal complex compound of (a), wherein M is Ir, m and n are integers of 1 to 2, and m + n = 3,
(N) In the general formula (1), L ₁ is a bidentate ligand of any one of the general formulas (15) to (17), and L ₂ is a bidentate ligand of the general formula (21) The metal complex compound of (a), wherein M is Ir, m and n are integers of 1 to 2, and m + n = 3,
(O) In the general formula (1), L ₁ is a bidentate ligand of any one of the general formulas (15) to (17), and L ₂ is a bidentate ligand of the general formula (22) The metal complex compound of (a), wherein M is Ir, m and n are integers of 1 to 2, and m + n = 3,

(P) In an organic electroluminescence device in which an organic thin film layer composed of one or more layers having at least a light-emitting layer is sandwiched between an anode and a cathode, at least one of the organic thin film layers comprises (a) to (o) An organic electroluminescence device containing any of the metal complex compounds of
(Q) The organic electroluminescence device of (p), wherein the light emitting layer contains any of the metal complex compounds of (a) to (o) as a light emitting material,
(R) The organic electroluminescent element of (p), wherein the light emitting layer contains the metal complex compound of any one of (a) to (o) as a dopant,
(S) An electron injection layer and / or an electron transport layer is provided between the light emitting layer and the cathode, and the electron injection layer and / or the electron transport layer contains a π electron deficient nitrogen-containing heterocyclic derivative as a main component. (P) The organic electroluminescent element of (p), (t) The organic electroluminescent element of (p) by which the reducing dopant is added to the interface area | region of a cathode and an organic thin film layer is provided.

  The present invention succeeded in developing a novel metal complex compound having one or two types of bidentate ligands. Moreover, an organic EL device using such a metal complex compound has high luminous efficiency and has succeeded in achieving a deep color of the device.

The present invention provides a metal complex compound represented by the following general formula (1).
(L ₁ ) _m M (L ₂ ) _n (1)
[In General Formula (1), M is a metal atom of iridium (Ir), platinum (Pt), rhodium (Rh) or palladium (Pd), and L ₁ and L ₂ are bidentate ligands different from each other. is there. m is an integer of 1 to 3, n is an integer of 0 to 1, and m + n is an integer of 2 or 3. ]
The partial structure (L ₁ ) _m M in the general formula (1) has the structure shown in the general formulas (2) to (17) as described in detail in the above (a) to (f). Further, the partial structure M (L ₂ ) _n in the general formula (1) has the structure shown in the general formulas (18) to (22) as described in detail in the above (g). Furthermore, Ir and Pt complex compounds described in (h) to (j) are given as special examples represented by the general formula (1).
Further, the present invention provides an organic electroluminescence device in which an organic thin film layer comprising at least one light emitting layer or a plurality of light emitting layers is sandwiched between an anode and a cathode, wherein at least one layer of the organic thin film layer has the general formula ( The organic electroluminescent element containing the metal complex compound represented by 1) is provided.
The organic electroluminescent element of this invention contains the metal compound by which a light emitting layer is represented with General formula (1) as a light emitting material and / or a dopant. The organic electroluminescence device of the present invention has an electron injection layer and / or an electron transport layer between a light emitting layer and a cathode, and the electron injection layer and / or the electron transport layer is a π electron deficient nitrogen-containing heterocyclic derivative. Is contained as a main component. In the organic electroluminescence device of the present invention, a reducing dopant is added to the interface region between the cathode and the organic thin film layer.
First, specific examples of groups constituting L ₁ and L ₂ that can be used in the present invention will be described below.
In the general formulas (2) to (6), the aryl group having 5 to 40 nuclear carbon atoms which may have a substituent of the A ring is preferably one having 6 to 30 nuclear carbon atoms, and 6 to 18 nuclear atoms. Are more preferred. Examples of the aryl group serving as a mother skeleton having 6 to 18 nucleus atoms include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 1-anthryl group, a 2-anthryl group, a 9-anthryl group, and a 1-phenanthryl group. 2-phenanthryl group, 3-phenanthryl group, 4-phenanthryl group, 9-phenanthryl group, 1-naphthacenyl group, 2-naphthacenyl group, 9-naphthacenyl group, 1-pyrenyl group, 2-pyrenyl group, 4-pyrenyl group 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, p-terphenyl-4-yl group, p-terphenyl-3-yl group, p-terphenyl-2-yl group, m -Terphenyl-4-yl group, m-terphenyl-3-yl group, m-terphenyl-2-yl group and the like can be mentioned.
Among these, a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 2-biphenylyl group, a 3-biphenylyl group, and a 4-biphenylyl group are preferable.
In the general formulas (2) to (6), the ring A cycloalkenyl group preferably has 4 to 15 nuclear carbon atoms, and is a cyclobutenyl group, cyclopentenyl group, cyclohexenyl group, cycloheptenyl group, indenyl group, 1,2 -Benzo-1,3-cycloheptadienyl group, bicyclo [2.2.2] oct-7-en-2-yl group and the like.

The alkyl group having 1 to 30 carbon atoms which may have a substituent is preferably an alkyl group having 1 to 10 carbon atoms, and examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, n- Butyl group, s-butyl group, isobutyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group N-dodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, neopentyl group, 1-methylpentyl group, 2-methylpentyl group 1-pentylhexyl group, 1-butylpentyl group, 1-heptyloctyl group, 3-methylpentyl group, hydroxymethyl group, 1-hydroxyethyl group, 2-hydro Siethyl group, 2-hydroxyisobutyl group, 1,2-dihydroxyethyl group, 1,3-dihydroxyisopropyl group, 2,3-dihydroxy-t-butyl group, 1,2,3-trihydroxypropyl group, aminomethyl group 1-aminoethyl group, 2-aminoethyl group, 2-aminoisobutyl group, 1,2-diaminoethyl group, 1,3-diaminoisopropyl group, 2,3-diamino-t-butyl group, 1,2, 3-triaminopropyl group, cyanomethyl group, 1-cyanoethyl group, 2-cyanoethyl group, 2-cyanoisobutyl group, 1,2-dicyanoethyl group, 1,3-dicyanoisopropyl group, 2,3-dicyano-t- Butyl group, 1,2,3-tricyanopropyl group, nitromethyl group, 1-nitroethyl group, 2-nitroethyl group, 1,2-dinitroethyl Group, 2,3-dinitro -t- butyl group, 1,2,3-trinitro-propyl group, a cyclopentyl group, a cyclohexyl group, cyclooctyl group, 3,5-tetramethyl cyclohexyl group.
Of these, methyl, ethyl, propyl, isopropyl, n-butyl, s-butyl, isobutyl, t-butyl, n-pentyl, n-hexyl, and n-heptyl are preferred. Group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group Group, n-octadecyl group, neopentyl group, 1-methylpentyl group, 1-pentylhexyl group, 1-butylpentyl group, 1-heptyloctyl group, cyclohexyl group, cyclooctyl group, 3,5-tetramethylcyclohexyl group is there.

The halogenated alkyl group having 2 to 30 carbon atoms that may have a substituent is preferably one having 2 to 10 carbon atoms. Examples of the halogenated alkyl group include a 1-chloroethyl group, a 2-chloroethyl group, 2-chloroisobutyl group, 1,2-dichloroethyl group, 1,3-dichloroisopropyl group, 2,3-dichloro-t-butyl group, 1,2,3-trichloropropyl group, bromomethyl group, 1-bromoethyl group 2-bromoethyl group, 2-bromoisobutyl group, 1,2-dibromoethyl group, 1,3-dibromoisopropyl group, 2,3-dibromo-t-butyl group, 1,2,3-tribromopropyl group, Iodomethyl group, 1-iodoethyl group, 2-iodoethyl group, 2-iodoisobutyl group, 1,2-diiodoethyl group, 1,3-diiodoisopropyl group, 2, -Diiodo-t-butyl group, 1,2,3-triiodopropyl group, fluoromethyl group, 1-fluoromethyl group, 2-fluoromethyl group, 2-fluoroisobutyl group, 1,2-difluoroethyl group, difluoromethyl Group, trifluoromethyl group, pentafluoroethyl group, perfluoroisopropyl group, perfluorobutyl group, perfluorocyclohexyl group and the like.
Among these, a fluoromethyl group, a trifluoromethyl group, a pentafluoroethyl group, a perfluoroisopropyl group, a perfluorobutyl group, and a perfluorocyclohexyl group are preferable.

  The aromatic heterocyclic group having 3 to 30 nuclear atoms which may have a substituent is preferably an aromatic heterocyclic group having 3 to 18 nuclear atoms. Examples of the aromatic heterocyclic group include 1-pyrrolyl group, 2 -Pyrrolyl group, 3-pyrrolyl group, pyrazinyl group, 2-pyridinyl group, 1-imidazolyl group, 2-imidazolyl group, 1-pyrazolyl group, 1-indolidinyl group, 2-indolidinyl group, 3-indolidinyl group, 5-indolidinyl group Group, 6-indolidinyl group, 7-indolidinyl group, 8-indolidinyl group, 2-imidazopyridinyl group, 3-imidazopyridinyl group, 5-imidazopyridinyl group, 6-imidazopyridinyl group, 7 -Imidazopyridinyl group, 8-Imidazopyridinyl group, 3-pyridinyl group, 4-pyridinyl group, 1-indolyl group, 2-indolyl group, 3-indolyl group, 4- Group, 5-indolyl group, 6-indolyl group, 7-indolyl group, 1-isoindolyl group, 2-isoindolyl group, 3-isoindolyl group, 4-isoindolyl group, 5-isoindolyl group, 6-isoindolyl group, 7- Isoindolyl group, 2-furyl group, 3-furyl group, 2-benzofuranyl group, 3-benzofuranyl group, 4-benzofuranyl group, 5-benzofuranyl group, 6-benzofuranyl group, 7-benzofuranyl group, 1-isobenzofuranyl group 3-isobenzofuranyl group, 4-isobenzofuranyl group, 5-isobenzofuranyl group, 6-isobenzofuranyl group, 7-isobenzofuranyl group, 2-quinolyl group, 3-quinolyl group 4-quinolyl group, 5-quinolyl group, 6-quinolyl group, 7-quinolyl group, 8-quinolyl group, 1-isoquinolyl 3-isoquinolyl group, 4-isoquinolyl group, 5-isoquinolyl group, 6-isoquinolyl group, 7-isoquinolyl group, 8-isoquinolyl group, 2-quinoxalinyl group, 5-quinoxalinyl group, 6-quinoxalinyl group, 1-carbazolyl group 2-carbazolyl group, 3-carbazolyl group, 4-carbazolyl group, 9-carbazolyl group, β-carbolin-1-yl, β-carbolin-3-yl, β-carbolin-4-yl, β-carboline-5 -Yl, β-carbolin-6-yl, β-carbolin-7-yl, β-carbolin-6-yl, β-carbolin-9-yl, 1-phenanthridinyl group, 2-phenanthridinyl group 3-phenanthridinyl group, 4-phenanthridinyl group, 6-phenanthridinyl group, 7-phenanthridinyl group, 8-phenanthridyl group Group, 9-phenanthridinyl group, 10-phenanthridinyl group, 1-acridinyl group, 2-acridinyl group, 3-acridinyl group, 4-acridinyl group, 9-acridinyl group, 1,7-phenanthroline- 2-yl group, 1,7-phenanthroline-3-yl group, 1,7-phenanthroline-4-yl group, 1,7-phenanthroline-5-yl group, 1,7-phenanthroline-6-yl group, 1 , 7-phenanthroline-8-yl group, 1,7-phenanthroline-9-yl group, 1,7-phenanthroline-10-yl group, 1,8-phenanthroline-2-yl group, 1,8-phenanthroline-3 -Yl group, 1,8-phenanthroline-4-yl group, 1,8-phenanthroline-5-yl group, 1,8-phenanthroline-6-yl group, 1,8-phenyl group Enanthroline-7-yl group, 1,8-phenanthroline-9-yl group, 1,8-phenanthroline-10-yl group, 1,9-phenanthroline-2-yl group, 1,9-phenanthroline-3-yl group 1,9-phenanthroline-4-yl group, 1,9-phenanthroline-5-yl group, 1,9-phenanthroline-6-yl group, 1,9-phenanthroline-7-yl group, 1,9-phenanthroline -8-yl group, 1,9-phenanthroline-10-yl group, 1,10-phenanthroline-2-yl group, 1,10-phenanthroline-3-yl group, 1,10-phenanthroline-4-yl group, 1,10-phenanthroline-5-yl group, 2,9-phenanthroline-1-yl group, 2,9-phenanthroline-3-yl group, 2,9-phenant Rin-4-yl group, 2,9-phenanthroline-5-yl group, 2,9-phenanthroline-6-yl group, 2,9-phenanthroline-7-yl group, 2,9-phenanthroline-8-yl group 2,9-phenanthroline-10-yl group, 2,8-phenanthroline-1-yl group, 2,8-phenanthroline-3-yl group, 2,8-phenanthroline-4-yl group, 2,8-phenanthroline -5-yl group, 2,8-phenanthroline-6-yl group, 2,8-phenanthroline-7-yl group, 2,8-phenanthroline-9-yl group, 2,8-phenanthroline-10-yl group, 2,7-phenanthroline-1-yl group, 2,7-phenanthroline-3-yl group, 2,7-phenanthroline-4-yl group, 2,7-phenanthroline-5-yl group 2,7-phenanthroline-6-yl group, 2,7-phenanthroline-8-yl group, 2,7-phenanthroline-9-yl group, 2,7-phenanthroline-10-yl group, 1-phenazinyl group, 2-phenazinyl group, 1-phenothiazinyl group, 2-phenothiazinyl group, 3-phenothiazinyl group, 4-phenothiazinyl group, 10-phenothiazinyl group, 1-phenoxazinyl group, 2-phenoxazinyl group, 3-phenoxazinyl group, 4-phenoxazinyl group, 10-phenoxazinyl group, 2-oxazolyl group, 4-oxazolyl group, 5-oxazolyl group, 2-oxadiazolyl group, 5-oxadiazolyl group, 3-flazanyl group, 2-thienyl group, 3-thienyl group, 2-methylpyrrol-1-yl group, 2-methylpyrrol-3-yl group, 2- Methylpyrrol-4-yl group, 2-methylpyrrol-5-yl group, 3-methylpyrrol-1-yl group, 3-methylpyrrol-2-yl group, 3-methylpyrrol-4-yl group, 3- Methylpyrrol-5-yl group, 2-t-butylpyrrol-4-yl group, 3- (2-phenylpropyl) pyrrol-1-yl group, 2-methyl-1-indolyl group, 4-methyl-1- Indolyl group, 2-methyl-3-indolyl group, 4-methyl-3-indolyl group, 2-t-butyl-1-indolyl group, 4-t-butyl 1-indolyl group, 2-t-butyl 3-indolyl group Group, 4-t-butyl-3-indolyl group and the like.

  Among these, 2-pyridinyl group, 1-indolidinyl group, 2-indolidinyl group, 3-indolidinyl group, 5-indolidinyl group, 6-indolidinyl group, 7-indolidinyl group, 8-indolidinyl group, 2-imidazo Pyridinyl group, 3-imidazopyridinyl group, 5-imidazopyridinyl group, 6-imidazopyridinyl group, 7-imidazopyridinyl group, 8-imidazopyridinyl group, 3-pyridinyl group, 4-pyridinyl group, 1-indolyl group, 2-indolyl group, 3-indolyl group, 4-indolyl group, 5-indolyl group, 6-indolyl group, 7-indolyl group, 1-isoindolyl group, 2-isoindolyl group, 3-isoindolyl group, 4-isoindolyl group, 5-isoindolyl group, 6-isoindolyl group, 7-isoindolyl group 1-carbazolyl group, 2-carbazolyl group, 3-carbazolyl group, 4-carbazolyl group, a 9-carbazolyl group.

The aryl group having 6 to 30 nuclear carbon atoms which may have a substituent is preferably an aryl group having 6 to 18 nuclear carbon atoms. Examples of the aryl group include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, 1-anthryl group, 2-anthryl group, 9-anthryl group, 1-phenanthryl group, 2-phenanthryl group, 3-phenanthryl group, 4-phenanthryl group, 9-phenanthryl group, 1-naphthacenyl group, 2-naphthacenyl group, 9-naphthacenyl group, 1-pyrenyl group, 2-pyrenyl group, 4-pyrenyl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, p-terphenyl-4-yl group, p- Terphenyl-3-yl group, p-terphenyl-2-yl group, m-terphenyl-4-yl group, m-terphenyl-3-yl group, m-terphenyl-2 Yl group, o-tolyl group, m-tolyl group, p-tolyl group, pt-butylphenyl group, p- (2-phenylpropyl) phenyl group, 3-methyl-2-naphthyl group, 4-methyl- 1-naphthyl group, 4-methyl-1-anthryl group, 4′-methylbiphenylyl group, 4 ″ -t-butyl-p-terphenyl-4-yl group, o-cumenyl group, m-cumenyl group, p -Cumenyl group, 2,3-xylyl group, 3,4-xylyl group, 2,5-xylyl group, mesityl group, perfluorophenyl group and the like.
Among these, phenyl group, 1-naphthyl group, 2-naphthyl group, 9-phenanthryl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, p-tolyl group, 3,4 -Xylyl group.

  The aralkyl group having 7 to 40 carbon atoms which may have a substituent is preferably one having 7 to 18 carbon atoms, and examples of the aralkyl group include benzyl group, 1-phenylethyl group and 2-phenylethyl group. 1-phenylisopropyl group, 2-phenylisopropyl group, phenyl-t-butyl group, α-naphthylmethyl group, 1-α-naphthylethyl group, 2-α-naphthylethyl group, 1-α-naphthylisopropyl group, 2-α-naphthylisopropyl group, β-naphthylmethyl group, 1-β-naphthylethyl group, 2-β-naphthylethyl group, 1-β-naphthylisopropyl group, 2-β-naphthylisopropyl group, 1-pyrrolylmethyl group 2- (1-pyrrolyl) ethyl group, p-methylbenzyl group, m-methylbenzyl group, o-methylbenzyl group, p-chlorobenzyl group, m- Lorobenzyl group, o-chlorobenzyl group, p-bromobenzyl group, m-bromobenzyl group, o-bromobenzyl group, p-iodobenzyl group, m-iodobenzyl group, o-iodobenzyl group, p-hydroxybenzyl group M-hydroxybenzyl group, o-hydroxybenzyl group, p-aminobenzyl group, m-aminobenzyl group, o-aminobenzyl group, p-nitrobenzyl group, m-nitrobenzyl group, o-nitrobenzyl group, p -Cyanobenzyl group, m-cyanobenzyl group, o-cyanobenzyl group, 1-hydroxy-2-phenylisopropyl group, 1-chloro-2-phenylisopropyl group and the like, preferably benzyl group, p-cyano Benzyl group, m-cyanobenzyl group, o-cyanobenzyl group, 1-phenylethyl group, 2-phenyl An ethyl group, a 1-phenylisopropyl group, and a 2-phenylisopropyl group.

  As a C2-C30 alkenyl group which may have a substituent, a C2-C16 thing is preferable. Examples of alkenyl groups include vinyl, allyl, 1-butenyl, 2-butenyl, 3-butenyl, 1,3-butanedienyl, 1-methylvinyl, styryl, 2,2-diphenylvinyl. Group, 1,2-diphenylvinyl group, 1-methylallyl group, 1,1-dimethylallyl group, 2-methylallyl group, 1-phenylallyl group, 2-phenylallyl group, 3-phenylallyl group, 3,3- Examples include diphenylallyl group, 1,2-dimethylallyl group, 1-phenyl-1-butenyl group, 3-phenyl-1-butenyl group, and preferably styryl group, 2,2-diphenylvinyl group, 1,2 -A diphenylvinyl group.

The arylamino group having 6 to 40 nuclear carbon atoms which may have a substituent and the alkylamino group having 1 to 40 carbon atoms which may have a substituent are represented by -NQ ₁ Q _2, and Q ₁ and As examples of Q ₂ , those having 1 to 20 carbon atoms are preferable independently, and examples other than the hydrogen atom include the same examples as those described for the alkyl group and aryl group.

Examples of the alkylsilyl group having 3 to 30 carbon atoms which may have a substituent include a trimethylsilyl group, a triethylsilyl group, a t-butyldimethylsilyl group, a vinyldimethylsilyl group, and a propyldimethylsilyl group.
Examples of the arylsilyl group having 6 to 30 carbon atoms which may have a substituent include a triphenylsilyl group, a phenyldimethylsilyl group, and a t-butyldiphenylsilyl group.
Examples of the halogen atom include fluorine, chlorine, bromine, iodine and the like.
Examples of the substituent R in —S (R) O ₂ and —S (R) O include the same groups as those described above.
An alkoxy group 1 to 30 carbon atoms which may have a substituent is a group represented by -OX _1, examples of X ₁ is preferably has 1 to 10 carbon atoms, the alkyl group, halogen Examples similar to those described for the alkyl group and aryl group.
Examples of the ester group having 1 to 30 carbon atoms that may have a substituent include methyl ester, ethyl ester, and butyl ester.

  Examples of the cyclic structure that may be formed by bonding to each other include, for example, cycloalkanes having 4 to 12 carbon atoms such as cyclobutane, cyclopentane, cyclohexane, adamantane, norbornane, cyclobutene, cyclopentene, cyclohexene, cycloheptene, cyclooctene, and the like. C6-C12 cycloalkadiene such as cycloalkene, cyclohexadiene, cycloheptadiene, cyclooctadiene, etc. having 4 to 12 carbon atoms, C6-C6 such as benzene, naphthalene, phenanthrene, anthracene, pyrene, chrysene, acenaphthylene, etc. 50 aromatic rings and nitrogen-containing aromatic rings such as pyridine, quinoline and isoquinoline.

The nitrogen-containing aromatic heterocyclic group for the B ring preferably has 3 to 20 nuclear atoms, and more preferably has 3 to 10 nuclear atoms. Examples of the nitrogen-containing aromatic heterocyclic group include pyrazinyl group, pyridyl group, pyrimidinyl group, pyrazolyl group, imidazolyl group, indolizinyl group, imidazolpyridinyl group, quinolyl group, isoquinolyl group, quinoxalinyl group and the like.
Among these, a pyrazinyl group, a pyridyl group, a pyrimidinyl group, a pyrazolyl group, an imidazolyl group, a quinolyl group, and an isoquinolyl group are preferable.

Specific examples of the metal complex compound represented by the general formula (1) of the present invention are shown below, but are not limited to these exemplified compounds.

The organic EL device of the present invention is an organic EL device in which an organic thin film layer comprising at least one light emitting layer or a plurality of layers is sandwiched between a pair of electrodes comprising an anode and a cathode, and at least one of the organic thin film layers However, it contains the metal complex compound of the present invention.
As content of the metal complex compound of this invention in the said organic thin film layer, it is 0.1-100 weight% normally with respect to the mass of the whole light emitting layer, and it is preferable in it being 1-30 weight%.
In the organic EL device of the present invention, the light emitting layer preferably contains the metal complex compound of the present invention as a light emitting material. In addition, the light emitting layer is usually thinned by vacuum deposition or coating. However, since the coating process can simplify the manufacturing process, the layer containing the metal complex compound of the present invention is preferably formed by coating. .

  In the organic EL device of the present invention, the organic thin film layer is a light emitting layer when the organic thin film layer is a single layer type, and this light emitting layer contains the metal complex compound of the present invention. In addition, multilayer organic EL elements include (anode / hole injection layer (hole transport layer) / light emitting layer / cathode), (anode / light emitting layer / electron injection layer (electron transport layer) / cathode), ( Anode / hole injection layer (hole transport layer) / light emitting layer / electron injection layer (electron transport layer) / cathode) and the like.

  The anode of the organic EL device of the present invention supplies holes to a hole injection layer, a hole transport layer, a light emitting layer and the like, and it is effective to have a work function of 4.5 eV or more. As a material for the anode, a metal, an alloy, a metal oxide, an electrically conductive compound, a mixture thereof, or the like can be used. Specific examples of the material of the anode include conductive metal oxides such as tin oxide, zinc oxide, indium oxide, and indium tin oxide (ITO), or metals such as gold, silver, chromium, nickel, and these conductive metals. Mixtures or laminates of oxides and metals, inorganic conductive materials such as copper iodide and copper sulfide, organic conductive materials such as polyaniline, polythiophene and polypyrrole, and laminates of these with ITO, etc. In particular, it is preferable to use ITO from the viewpoint of productivity, high conductivity, transparency, and the like. The film thickness of the anode can be appropriately selected depending on the material.

  The cathode of the organic EL device of the present invention supplies electrons to an electron injection layer, an electron transport layer, a light emitting layer, and the like. As a material of the cathode, metals, alloys, metal halides, metal oxides, electric conduction Or a mixture of these can be used. Specific examples of cathode materials include alkali metals (eg, Li, Na, K, etc.) and their fluorides or oxides, alkaline earth metals (eg, Mg, Ca, etc.) and their fluorides or oxides, gold Silver, lead, aluminum, sodium-potassium alloy or sodium-potassium mixed metal, lithium-aluminum alloy or lithium-aluminum mixed metal, magnesium-silver alloy or magnesium-silver mixed metal, or rare earth metals such as indium and ytterbium, etc. Can be mentioned. Among these, aluminum, lithium-aluminum alloy or lithium-aluminum mixed metal, magnesium-silver alloy or magnesium-silver mixed metal are preferable. The cathode may have a single layer structure of the material or a laminated structure of layers containing the material. For example, a laminated structure of aluminum / lithium fluoride and aluminum / lithium oxide is preferable. The film thickness of the cathode can be appropriately selected depending on the material.

  The hole injection layer and the hole transport layer of the organic EL device of the present invention have any one of a function of injecting holes from the anode, a function of transporting holes, and a function of blocking electrons injected from the cathode. If it is what. Specific examples include carbazole derivatives, triazole derivatives, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, styrylanthracene derivatives. , Fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aromatic tertiary amine compounds, styrylamine compounds, aromatic dimethylidin compounds, porphyrin compounds, polysilane compounds, poly (N-vinylcarbazole) derivatives, aniline compounds Examples include copolymers, thiophene oligomers, conductive polymer oligomers such as polythiophene, organosilane derivatives, and metal complex compounds of the present invention. Further, the hole injection layer and the hole transport layer may have a single layer structure composed of one or more of the materials, or a multilayer structure composed of a plurality of layers having the same composition or different compositions. May be.

  The electron injection layer and the electron transport layer of the organic EL device of the present invention have any one of the function of injecting electrons from the cathode, the function of transporting electrons, and the function of blocking holes injected from the anode. If it is. Specific examples include triazole derivatives, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, fluorenone derivatives, anthraquinodimethane derivatives, anthrone derivatives, diphenylquinone derivatives, thiopyrandioxide derivatives, carbodiimide derivatives, fluorenylidenemethane derivatives. , Represented by metal complexes of aromatic ring tetracarboxylic anhydrides such as distyrylpyrazine derivatives, naphthalene and perylene, phthalocyanine derivatives, 8-quinolinol derivatives, metal phthalocyanines, benzoxazoles and benzothiazoles as ligands Examples include various metal complexes, organosilane derivatives, and metal complex compounds of the present invention. In addition, the electron injection layer and the electron transport layer may have a single layer structure composed of one or more of the materials, or a multilayer structure composed of a plurality of layers having the same composition or different compositions. Good.

Further, examples of the electron transport material used for the electron injection layer and the electron transport layer include the following compounds.

In the organic EL device of the present invention, it is preferable that the electron injection layer and / or the electron transport layer contain a π electron deficient nitrogen-containing heterocyclic derivative as a main component.
As the π-electron deficient nitrogen-containing heterocyclic derivative, a nitrogen-containing 5-membered ring derivative selected from a benzimidazole ring, a benztriazole ring, a pyridinoimidazole ring, a pyrimidinoimidazole ring, and a pyridazinoimidazole ring, pyridine Preferred examples include nitrogen-containing 6-membered ring derivatives composed of a ring, a pyrimidine ring, a pyrazine ring, and a triazine ring. Preferred examples of the nitrogen-containing 5-membered ring derivative include structures represented by the following general formula B-I. As the nitrogen-containing 6-membered ring derivative, structures represented by the following general formulas C-I, C-II, C-III, C-IV, CV and C-VI are preferably exemplified, and particularly preferably, It is a structure represented by general formula CI and C-II.

一般式（Ｂ−Ｉ）において、Ｌ^Bは二価以上の連結基を表し、好ましくは、炭素、ケイ素、窒素、ホウ素、酸素、硫黄、金属、金属イオン等で形成される連結基であり、より好ましくは炭素原子、窒素原子、ケイ素原子、ホウ素原子、酸素原子、硫黄原子、芳香族炭化水素環、芳香族へテロ環であり、さらに好ましくは炭素原子、ケイ素原子、芳香族炭化水素環、芳香族へテロ環である。

In the general formula ^(B-I), L B represents a divalent or higher linking group, preferably, the linking group formed by carbon, silicon, nitrogen, boron, oxygen, sulfur, metals, metal ions, etc., More preferably a carbon atom, a nitrogen atom, a silicon atom, a boron atom, an oxygen atom, a sulfur atom, an aromatic hydrocarbon ring, an aromatic heterocycle, and still more preferably a carbon atom, a silicon atom, an aromatic hydrocarbon ring, An aromatic heterocycle.

L ^B may have a substituent, preferably an alkyl group as a substituent, an alkenyl group, an alkynyl group, an aromatic hydrocarbon group, an amino group, an alkoxy group, an aryloxy group, an acyl group, an alkoxycarbonyl group, Aryloxycarbonyl group, acyloxy group, acylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfonylamino group, sulfamoyl group, carbamoyl group, alkylthio group, arylthio group, sulfonyl group, halogen atom, cyano group, aromatic hetero complex A cyclic group, more preferably an alkyl group, an aryl group, an alkoxy group, an aryloxy group, a halogen atom, a cyano group, or an aromatic heterocyclic group, and still more preferably an alkyl group, an aryl group, an alkoxy group, an aryloxy group. An aromatic heterocyclic group Particularly preferably an alkyl group, an aryl group, an alkoxy group, an aromatic heterocyclic group.

Specific examples of the linking group represented by L ^B may include the following.

In the general formula (BI), X ^B2 represents —O—, —S— or ═N—R ^B2 . R ^B2 represents a hydrogen atom, an aliphatic hydrocarbon group, an aryl group or a heterocyclic group.
The aliphatic hydrocarbon group represented by R ^B2 is a linear, branched or cyclic alkyl group (preferably an alkyl group having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, and particularly preferably 1 to 8 carbon atoms). And examples thereof include methyl, ethyl, isopropyl, t-butyl, n-octyl, n-decyl, n-hexadecyl, cyclopropyl, cyclopentyl, cyclohexyl and the like, and an alkenyl group (preferably having 2 to 2 carbon atoms). 20, more preferably an alkenyl group having 2 to 12 carbon atoms, particularly preferably 2 to 8 carbon atoms, and examples thereof include a vinyl group, an allyl group, a 2-butenyl group, and a 3-pentenyl group.), An alkynyl group (Preferably an alkynyl group having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, particularly preferably 2 to 8 carbon atoms, such as a propargyl group, 3 Pentynyl group and the like.), More preferably an alkyl group.
The aryl group represented by R ^B2 is a monocyclic or condensed ring aryl group, preferably an aryl group having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, still more preferably 6 to 12 carbon atoms, For example, phenyl, 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 2-methoxyphenyl, 3-trifluoromethylphenyl, pentafluorophenyl, 1-naphthyl, 2-naphthyl and the like can be mentioned.

The heterocyclic group represented by R ^B2 is a monocyclic or condensed heterocyclic group (preferably a heterocyclic group having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, still more preferably 2 to 10 carbon atoms). Yes, preferably an aromatic heterocyclic group containing at least one of a nitrogen atom, an oxygen atom, a sulfur atom, and a selenium atom, such as pyrrolidine, piperidine, piperazine, morpholine, thiophene, selenophene, furan, pyrrole, imidazole , Pyrazole, pyridine, pyrazine, pyridazine, pyrimidine, triazole, triazine, indole, indazole, purine, thiazoline, thiazole, thiadiazole, oxazoline, oxazole, oxadiazole, quinoline, isoquinoline, phthalazine, naphthyridine, quinoxaline, quinazoline, cinnoline, pteri , Acridine, phenanthroline, phenazine, tetrazole, benzimidazole, benzoxazole, benzothiazole, benzotriazole, tetrazaindene, carbazole, azepine, etc., preferably furan, thiophene, pyridine, pyrazine, pyrimidine, pyridazine, triazine Quinoline, phthalazine, naphthyridine, quinoxaline and quinazoline, more preferably furan, thiophene, pyridine and quinoline, and still more preferably quinoline.
The aliphatic hydrocarbon group, aryl group, and heterocyclic group represented by R ^B2 may have a substituent, and examples thereof include the same as L ^B described above.
R ^B2 is preferably an alkyl group, an aryl group, or an aromatic heterocyclic group, more preferably an aryl group or an aromatic heterocyclic group, and still more preferably an aryl group.

X ^B2 is preferably —O— or ═N—R ^B2 , more preferably ═N—R ^B2 , and particularly preferably ═N—Ar ^B2 {Ar ^B2 is an aryl group (preferably having 6 carbon atoms). To 30, more preferably 6 to 20 carbon atoms, still more preferably an aryl group having 6 to 12 carbon atoms) or an aromatic heterocyclic group (preferably 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, still more preferably Is an aromatic heterocyclic group having 2 to 10 carbon atoms, preferably an aryl group. }.

Z ^B2 represents an atomic group necessary for forming an aromatic ring. The aromatic ring formed by Z ^B2 may be either an aromatic hydrocarbon ring or an aromatic heterocycle. Specific examples include, for example, a benzene ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, a triazine ring, and a pyrrole. Ring, furan ring, thiophene ring, selenophene ring, tellurophen ring, imidazole ring, thiazole ring, selenazole ring, tellurazole ring, thiadiazole ring, oxadiazole ring, pyrazole ring, etc., preferably benzene ring, pyridine ring, pyrazine A ring, a pyrimidine ring and a pyridazine ring, more preferably a benzene ring, a pyridine ring and a pyrazine ring, still more preferably a benzene ring and a pyridine ring, and particularly preferably a pyridine ring. The aromatic ring formed by Z ^B2 may further form a condensed ring with another ring and may have a substituent. As a substituent, preferably an alkyl group, alkenyl group, alkynyl group, aryl group, amino group, alkoxy group, aryloxy group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, acyloxy group, acylamino group, alkoxycarbonylamino group Aryloxycarbonylamino group, sulfonylamino group, sulfamoyl group, carbamoyl group, alkylthio group, arylthio group, sulfonyl group, halogen atom, cyano group, heterocyclic group, more preferably alkyl group, aryl group, alkoxy group, An aryloxy group, a halogen atom, a cyano group and a heterocyclic group, more preferably an alkyl group, an aryl group, an alkoxy group, an aryloxy group and an aromatic heterocyclic group, particularly preferably an alkyl group, an aryl group, Al Alkoxy group, an aromatic heterocyclic group.
n ^B2 is an integer of 1 to 4, preferably 2 to 3.

Of the compounds represented by the general formula (BI), more preferred is a compound represented by the following general formula (B-II).

In general formula (B-II), R ^B71 , R ^B72 and R ^B73 have the same ^{meanings as} R ^B2 in general formula ( ^BI ), respectively, and the preferred ranges are also the same.
Z ^B71 , Z ^B72 and Z ^B73 are the same as Z ^B2 in formula ( ^BI ), respectively, and the preferred ranges are also the same.
L ^B71 , L ^B72 and L ^B73 each represent a linking group, and examples thereof include a divalent example of L ^{B in} the general formula (BI), preferably a single bond or a divalent aromatic carbonization. A linking group composed of a hydrogen ring group, a divalent aromatic heterocyclic group, and a combination thereof, more preferably a single bond. L ^B71 , L ^B72 and L ^B73 may have a substituent, and examples of the substituent include those similar to L ^{B in the} general formula (BI).
Y represents a nitrogen atom, a 1,3,5-benzenetriyl group or a 2,4,6-triazinetriyl group. The 1,3,5-benzenetriyl group may have a substituent at the 2,4,6-position, and examples of the substituent include an alkyl group, an aromatic hydrocarbon ring group, and a halogen atom. It is done.

Specific examples of the nitrogen-containing 5-membered ring derivative represented by the general formula (BI) or (B-II) are shown below, but are not limited to these exemplified compounds.

(Cz-) _n A (CI)
Cz (-A) _m (C-II)
{In the formula, Cz is a substituted or unsubstituted carbazolyl group, arylcarbazolyl group or carbazolylalkylene group, and A is a group formed from a site represented by the following general formula (A). n and m are integers of 1 to 3, respectively.
(M) _p − (L) _q − (M ′) _r (A)
(M and M ′ are each independently a nitrogen-containing heteroaromatic ring having 2 to 40 carbon atoms to form a ring, and the ring may or may not have a substituent. M and M ′ may be the same or different, and L is a single bond, an arylene group having 6 to 30 carbon atoms, a cycloalkylene group having 5 to 30 carbon atoms, or a heteroaromatic ring having 2 to 30 carbon atoms. , May or may not have a substituent bonded to the ring, p is 0 to 2, q is 1 to 2, and r is an integer of 0 to 2. However, p + r is 1 or more. is there.)}

The bonding mode of the general formulas (C-I) and (C-II) is specifically represented by the number of parameters n and m as shown in the following table.

Further, the bonding mode of the group represented by the general formula (A) is specifically the form described in (1) to (16) in the following table depending on the number of parameters p, q and r.

  In the general formulas (CI) and (C-II), when Cz is bonded to A, it may be bonded to any part of M, L, M ′ representing A. For example, in Cz-A in which m = n = 1, when p = q = r = 1 ((6) in the table), A becomes M-L-M 'and Cz-M-L-M', M- L (-Cz) -M 'and ML-M'-Cz are represented as three bonding modes. Similarly, for example, in the case of Cz-A-Cz in which n = 2 in the general formula (CI), when p = q = 1 and r = 2 ((7) in the table), A is M-LM It becomes '-M' or ML (-M ')-M' and is represented as the following binding mode.

Specific examples represented by the general formulas (CI) and (C-II) include the following structures, but are not limited to these examples.

（式中、Ａｒ₁₁〜Ａｒ₁₃は、それぞれ一般式（Ｂ−Ｉ）のＲ^B2と同様の基を示し、具体例も同様であり、Ａｒ₁〜Ａｒ₃は、一般式（Ｂ−Ｉ）のＲ^B2と同様の基を２価にしたものを示し、具体例も同様である。）
一般式（Ｃ−ＩＩＩ)の具体例を以下に示すが、これに限定されない。

(In the formula, Ar _{11 to} Ar ₁₃ each represent the same group as R ^{B2 in the} general formula (BI), and specific examples thereof are also the same. Ar _{1 to} Ar ₃ are the same in the general formula (BI)). the same groups as R ^B2 in indicates those divalent, examples versa.)
Specific examples of the general formula (C-III) are shown below, but are not limited thereto.

（式中、Ｒ₅₉〜Ｒ₆₂は、それぞれ一般式（Ｂ−Ｉ）のＲ^B2と同様の基を示し、具体例も同様である。）
一般式（Ｃ−ＩＶ）の具体例を以下に示すが、これらに限定されない。

(In the formula, R _{59 to} R ₆₂ each represent the same group as R ^{B2 in} formula (BI), and specific examples thereof are also the same).
Although the specific example of general formula (C-IV) is shown below, it is not limited to these.

（式中、Ａｒ₄〜Ａｒ₆は、それぞれ一般式（Ｂ−Ｉ）のＲ^B2と同様の基を示し、具体例も同様である。）
一般式（Ｃ−Ｖ）の具体例を以下に示すが、これに限定されない。

(In formula, Ar < ₄ > -Ar < ₆ > respectively shows the group similar to R ^<B2 > of general formula (BI), and a specific example is also the same.)
Although the specific example of general formula (CV) is shown below, it is not limited to this.

（式中、Ａｒ₇〜Ａｒ₁₀は、それぞれ一般式（Ｂ−Ｉ）のＲ^B2と同様の基を示し、具体例も同様である。）
一般式（Ｃ−ＶＩ）の具体例を以下に示すが、これに限定されない。

(In formula, Ar < ₇ > -Ar < ₁₀ > shows the group similar to R ^<B2 > of general formula (BI) respectively, and a specific example is also the same.)
Although the specific example of general formula (C-VI) is shown below, it is not limited to this.

In the organic EL device of the present invention, it is preferable to use an insulator or a semiconductor inorganic compound as a substance constituting the electron injection / transport layer. If the electron injecting / transporting layer is made of an insulator or a semiconductor, current leakage can be effectively prevented and the electron injecting property can be improved. As such an insulator, it is preferable to use at least one metal compound selected from the group consisting of alkali metal chalcogenides, alkaline earth metal chalcogenides, alkali metal halides and alkaline earth metal halides. If the electron injecting / transporting layer is composed of these alkali metal chalcogenides or the like, it is preferable in that the electron injecting property can be further improved.
Specifically, preferable alkali metal chalcogenides include, for example, Li ₂ O, K ₂ O, Na ₂ S, Na ₂ Se, and Na ₂ O, and preferable alkaline earth metal chalcogenides include, for example, CaO, BaO. , SrO, BeO, BaS and CaSe. Further, preferable alkali metal halides include, for example, LiF, NaF, KF, LiCl, KCl, and NaCl. Examples of preferable alkaline earth metal halides include fluorides such as CaF ₂ , BaF ₂ , SrF ₂ , MgF ₂ and BeF ₂ , and halides other than fluorides.

The semiconductor constituting the electron injecting / transporting layer includes at least one element of Ba, Ca, Sr, Yb, Al, Ga, In, Li, Na, Cd, Mg, Si, Ta, Sb, and Zn. One kind of oxide, nitride, oxynitride or the like may be used alone or in combination of two or more kinds. Moreover, it is preferable that the inorganic compound which comprises an electron carrying layer is a microcrystal or an amorphous insulating thin film. If the electron transport layer is composed of these insulating thin films, a more uniform thin film is formed, and pixel defects such as dark spots can be reduced. Examples of such inorganic compounds include the alkali metal chalcogenides, alkaline earth metal chalcogenides, alkali metal halides, and alkaline earth metal halides described above.
Furthermore, in the organic EL device of the present invention, the electron injection layer and / or the electron transport layer may contain a reducing dopant having a work function of 2.9 eV or less. In the present invention, the reducing dopant is a compound that increases the electron injection efficiency.

  In the present invention, a reducing dopant is preferably added to the interface region between the cathode and the organic thin film layer, and at least a part of the organic layer contained in the interface region is reduced and anionized. Preferred reducing dopants include alkali metals, alkaline earth metal oxides, alkaline earth metals, rare earth metals, alkali metal oxides, alkali metal halides, alkaline earth metal oxides, alkaline earth metals. At least one compound selected from the group consisting of halides of rare earth metals, rare earth metal oxides or halides of rare earth metals, alkali metal complexes, alkaline earth metal complexes, and rare earth metal complexes. More specifically, preferable reducing dopants include Na (work function: 2.36 eV), K (work function: 2.28 eV), Rb (work function: 2.16 eV) and Cs (work function: 1.95 eV). ) And at least one alkali metal selected from the group consisting of Ca (work function: 2.9 eV), Sr (work function: 2.0 to 2.5 eV), and Ba (work function: 2.52 eV). Examples include at least one alkaline earth metal selected from the group, and a work function of 2.9 eV is particularly preferable. Among these, a more preferable reducing dopant is at least one alkali metal selected from the group consisting of K, Rb and Cs, more preferably Rb or Cs, and most preferably Cs. These alkali metals have particularly high reducing ability, and the addition of a relatively small amount to the electron injection region can improve the light emission luminance and extend the life of the organic EL element.

Examples of the alkaline earth metal oxide include BaO, SrO, CaO and Ba _x Sr _1-x O (0 <x <1) mixed with these, Ba _x Ca _1-x O (0 <x <1). 1) can be mentioned as a preferable one. Examples of the alkali metal oxide or alkali metal fluoride include LiF, Li ₂ O, and NaF. The alkali metal complex, alkaline earth metal complex, and rare earth metal complex are not particularly limited as long as they contain at least one of alkali metal ions, alkaline earth metal ions, and rare earth metal ions as metal ions. Examples of the ligand include quinolinol, benzoquinolinol, acridinol, phenanthridinol, hydroxyphenyloxazole, hydroxyphenylthiazole, hydroxydiaryloxadiazole, hydroxydiarylthiadiazole, hydroxyphenylpyridine, hydroxyphenylbenzimidazole, hydroxybenzo Examples include, but are not limited to, triazole, hydroxyfulborane, bipyridyl, phenanthroline, phthalocyanine, porphyrin, cyclopentadiene, β-diketones, azomethines, and derivatives thereof.

Moreover, as a preferable form of a reducing dopant, it forms in a layer form or an island form. A preferable film thickness when used in a layered form is 0.05 to 8 nm.
As a method for forming an electron injecting / transporting layer containing a reducing dopant, an organic substance that is a light emitting material or an electron injecting material for forming an interface region is simultaneously deposited while depositing a reducing dopant by a resistance heating vapor deposition method. A method in which a reducing dopant is dispersed in is preferable. The dispersion concentration is 100: 1 to 1: 100, preferably 5: 1 to 1: 5, as a molar ratio. When forming the reducing dopant in layers, after forming the light emitting material or the electron injecting material, which is an organic layer at the interface, into layers, the reducing dopant is vapor-deposited by resistance heating evaporation method, preferably with a film thickness of 0. Formed at 5 nm to 15 nm. When forming the reducing dopant in an island shape, after forming the light emitting material or electron injecting material which is the organic layer at the interface, the reducing dopant is vapor-deposited by resistance heating vapor deposition method alone, preferably 0.05 Form at ˜1 nm.

  The light emitting layer of the organic EL device of the present invention can inject holes from the anode or the hole injection layer when an electric field is applied, and can inject electrons from the cathode or the electron injection layer. And holes) by the force of an electric field, a field for recombination of electrons and holes, and a function to connect this to light emission. The light emitting layer of the organic EL device of the present invention preferably contains at least the metal complex compound of the present invention, and may contain a host material using the metal complex compound as a guest material. Examples of the host material include those having a carbazole skeleton, those having a diarylamine skeleton, those having a pyridine skeleton, those having a pyrazine skeleton, those having a triazine skeleton, and those having an arylsilane skeleton. It is preferable that T1 (energy level of the lowest triplet excited state) of the host material is larger than the T1 level of the guest material. The host material may be a low molecular compound or a high molecular compound. Further, by co-evaporating the host material and a light emitting material such as the metal complex compound, a light emitting layer in which the light emitting material is doped in the host material can be formed.

In the organic EL device of the present invention, the method for forming each layer is not particularly limited, but a vacuum deposition method, an LB method, a resistance heating deposition method, an electron beam method, a sputtering method, a molecular lamination method, a coating method. Various methods such as a spin coating method, a casting method, a dip coating method, an ink jet method, and a printing method can be used. In the present invention, a coating method that is a coating method is preferable.
In addition, the organic thin film layer containing the metal complex compound of the present invention can be prepared by vacuum deposition, molecular beam deposition (MBE), or solution dipping in a solvent, spin coating, casting, bar coating, roll It can be formed by a known method such as a coating method.
In the coating method, the metal complex compound of the present invention can be dissolved in a solvent to prepare a coating solution, and the coating solution can be applied on a desired layer (or electrode) and dried. The coating solution may contain a resin, and the resin can be dissolved in a solvent or dispersed. As the resin, a non-conjugated polymer (for example, polyvinyl carbazole) or a conjugated polymer (for example, a polyolefin-based polymer) can be used. More specifically, for example, polyvinyl chloride, polycarbonate, polystyrene, polymethyl methacrylate, polybutyl methacrylate, polyester, polysulfone, polyphenylene oxide, polybutadiene, poly (N-vinylcarbazole), hydrocarbon resin, ketone resin, phenoxy resin. , Polyamide, ethyl cellulose, vinyl acetate, ABS resin, polyurethane, melamine resin, unsaturated polyester resin, alkyd resin, epoxy resin, silicon resin and the like.
In addition, the thickness of each organic layer of the organic EL element of the present invention is not particularly limited, but in general, if the film thickness is too thin, defects such as pinholes are likely to occur. Conversely, if it is too thick, a high applied voltage is required and efficiency is increased. Usually, the range of several nm to 1 μm is preferable because of deterioration.

（１）配位子Ａの合成
窒素気流下、１Ｌフラスコにテトラキス（トリフェニルホスフィン）パラジウム５ｍｍｏｌ（５．３ｇ）、３−ブロモ−４−メトキシベンゾニトリル９１ｍｍｏｌ（１９．３ｇ）及び２−ピリジル臭化亜鉛１１８ｍｍｏｌ（ＴＨＦ（テトラヒドロフラン）溶液２３６ｍＬ）を入れ、３時間還流反応させた。反応液を濃縮後、残渣を塩化メチレン３００ｍＬに溶解したものを８５％水酸化カリウム水溶液１００ｍＬで洗浄した。分離した有機層を３５％塩酸１００ｍＬで洗い、さらにその水層に８５％水酸化カリウム水溶液をｐＨ１２になるまで、投入した。ついで塩化メチレン３００ｍＬで抽出し、有機層を飽和塩化ナトリウム水溶液１００ｍＬで洗浄後、無水硫酸マグネシウムで乾燥した。ろ過後濃縮して得た固形物をシリカカラムクロマトグラフィー（ヘキサン：酢酸エチル＝９：１から５：５）で精製し、１３．５ｇの目的物を得た（収率７０％）。
¹H-NMR (CDCl₃): δ8.66(1H), δ8.11(1H), δ7.81(1H), δ7.73-7.69(1H), δ7.60-7.63(1H), δ7.22-7.25(1H), δ7.03(1H), δ3.90(3H) Next, the present invention will be described in more detail using examples.
Synthesis Example 1 (Synthesis of Compound (B25))
The following compound (B25) was synthesized in the following reaction process.

(1) Synthesis of Ligand A Under a nitrogen stream, 5 mmol (5.3 g) of tetrakis (triphenylphosphine) palladium, 91 mmol (19.3 g) of 3-bromo-4-methoxybenzonitrile and 2-pyridyl odor were added to a 1 L flask. Zinc halide (118 mmol) (THF (tetrahydrofuran) solution 236 mL) was added, and the mixture was refluxed for 3 hours. After concentrating the reaction solution, the residue dissolved in 300 mL of methylene chloride was washed with 100 mL of 85% aqueous potassium hydroxide. The separated organic layer was washed with 100 mL of 35% hydrochloric acid, and an 85% aqueous potassium hydroxide solution was added to the aqueous layer until the pH reached 12. Subsequently, extraction was performed with 300 mL of methylene chloride, and the organic layer was washed with 100 mL of a saturated aqueous sodium chloride solution and then dried over anhydrous magnesium sulfate. The solid substance obtained after filtration and concentration was purified by silica column chromatography (hexane: ethyl acetate = 9: 1 to 5: 5) to obtain 13.5 g of the desired product (yield 70%).
¹ H-NMR (CDCl ₃ ): δ8.66 (1H), δ8.11 (1H), δ7.81 (1H), δ7.73-7.69 (1H), δ7.60-7.63 (1H), δ7. 22-7.25 (1H), δ7.03 (1H), δ3.90 (3H)

(2) Synthesis of intermediate A 4.2 g of 2- (5-cyano-2-methoxyphenyl) pyridine (ligand A), 1.5 g of iridium chloride and 40 mL of 2-ethoxyethanol were placed in a 200 mL three-necked flask. The atmosphere was replaced with argon, and the mixture was heated to reflux with stirring for 10 hours. After returning to room temperature, the precipitate was filtered off, washed with ethanol and dichloromethane, and then dried in vacuo to obtain 2.7 g of a yellow solid (Intermediate A).

(3) Synthesis of Compound (B25) 2.7 g of Intermediate A, 0.5 g of acetylacetone, 2.6 g of sodium carbonate and 30 mL of 2-ethoxyethanol were placed in a 200 mL three-necked flask, purged with argon, and heated to reflux with stirring for 10 hours. did. After cooling to room temperature, the solid was filtered off, dichloromethane and water were added to the obtained solid, and the mixture was extracted with dichloromethane. The organic layer was dried over anhydrous sodium sulfate, concentrated, and purified by 100 g silica gel column chromatography to obtain 0.8 g of a light yellow solid. Further sublimation purification was performed to obtain 0.2 g of the target compound. The structure was confirmed by FD-MS. The measurement results are shown below.
FD-MS: calcd.for IrC ₃₁ H ₂₅ N ₄ O ₄ = 710, found m / z = 710 (100)

Synthesis Example 2 (Synthesis of Compound (B35))
Compound (B35) was synthesized in the following reaction step.

(1) Synthesis of 2- (2-methyl-5-nitrophenyl) pyridine Under a nitrogen stream, tetrakis (triphenylphosphine) palladium 4 mmol (4.6 g) and 2-iodo-2-nitrotoluene 502 mmol (132 g) in a 3 L flask Then, 526 mmol of 2-pyridyl zinc bromide (1052 mL of THF solution) was added, and the mixture was refluxed for 4 hours. After concentrating the reaction solution, the residue was treated with 500 mL of toluene and 300 mL of 10% hydrochloric acid. The separated aqueous layer was neutralized with potassium hydroxide and extracted with 500 mL of toluene. After filtering insoluble matter, toluene was distilled off to obtain 52 g of the desired product (yield 48%).

(2) Synthesis of 2- (5-amino-2-methylphenyl) pyridine In an autoclave, 243 mmol (52 g) of 2- (2-methyl-5-nitrophenyl) pyridine, 10% Pd / C (manufactured by Aldrich, 50% wet) 25 g, 500 mL of ethyl acetate and 500 mL of ethanol were added. The mixture was reacted at 80 ° C. for 4 hours under 5 kg / cm ² hydrogen pressure. Pd / C was removed from the reaction mixture, and the filtrate was concentrated to obtain 44 g of the desired product (yield 98%).

(3) Synthesis of 2- (5-iodo-2-methylphenyl) pyridine 130 mmol (24 g) of 2- (5-amino-2-methylphenyl) pyridine, 150 mL of water, 50 mL of methylene chloride and 194 mmol of 98% sulfuric acid in a 500 mL flask (19 g) was added. It cooled to 7-15 degreeC, sodium nitrite 159mmol (11g) was added, and it was made to react at the same temperature for 5 minutes. Further, 193 mmol (32 g) of potassium iodide was added and reacted at 7 to 19 ° C. The resulting reaction solution was extracted with 500 mL of methylene chloride, and the solid obtained after concentration was purified by silica gel column chromatography (toluene) to obtain 26 g (yield 68%) of the desired product.

(4) Synthesis of 2- (5-cyano-2-methylphenyl) pyridine (ligand B) In a 200 mL flask, 88 mmol (26 g) of 2- (5-iodo-2-methylphenyl) pyridine and 106 mmol of copper cyanide ( 9.5 g) and 50 mL of dimethylformamide were added and heated to reflux for 4 hours. The reaction solution was treated with aqueous ammonia and extracted with toluene. The toluene extraction solution was passed through a silica column and further isolated by silica column chromatography (hexane: ethyl acetate = 7: 3). The obtained crude crystals were recrystallized with ethyl acetate / hexane and purified and dried to obtain 5.0 g of the final desired product (yield 29%).

(5) Synthesis of Intermediate B In a 100 mL flask, 5.0 mmol (1.5 g) of iridium chloride hydrate and 20.0 mmol (3.9 g) of 2- (5-cyano-2-methylphenyl) pyridine were added and reacted. The system was depressurized and purged with argon. Under a stream of argon, 35 mL of 2-ethoxyethanol was added and reacted for 14 hours under heating and reflux. After cooling, 100 mL of methanol was added to the resulting solution, and a yellow precipitate was collected by filtration. The product was further washed with 100 mL of methylene chloride to obtain 1.48 g (48%) of the desired product.

(6) Synthesis of Compound (B35) Intermediate B 1.14 mmol (1.4 g) and sodium carbonate 12.8 mmol (1.36 g) were placed in a 100 mL flask, and the reaction system was evacuated to perform argon substitution. Next, 2.85 mmol (0.28 g) of acetylacetone and 25 mL of 2-ethoxyethanol were added under an argon stream and reacted for 14 hours under heating and reflux. After cooling, the solvent was distilled off, and the resulting black solid was dissolved in 450 mL of methylene chloride and washed twice with 300 mL of saturated aqueous sodium chloride solution. The separated organic layer was dried over anhydrous magnesium sulfate, filtered and concentrated, and the resulting brown solid was purified twice by silica column chromatography (methylene chloride) to obtain 0.25 g of the desired product as yellow crystals ( Yield 16%).
FD-MS: calcd. For IrC ₃₁ H ₂₅ N ₄ O ₂ = 678, found m / z = 678 (100)
¹ H-NMR (CDCl ₃ ): δ8.51 (2H), δ8.15 (2H), δ7.80 (2H), δ6.75-7.22 (6H), δ5.15 (1H), δ2.78 ( 6H), δ 1.70 (6H)

Device fabrication example Example 1
A glass substrate with an ITO transparent electrode having a thickness of 25 mm × 75 mm × 0.7 mm was subjected to ultrasonic cleaning in isopropyl alcohol for 5 minutes and then UV ozone cleaning for 30 minutes. The glass substrate with the transparent electrode after the cleaning was mounted on the substrate holder of the vacuum deposition apparatus, and the following TPD232 was formed to a thickness of 85 nm so as to cover the transparent electrode on the surface where the transparent electrode was formed. . This TPD232 film functions as a hole injection layer. Next, the following 4,4 ′, 4 ″ -tris (carbazol-9-yl) -triphenylamine (TCTA) was formed on the TPD232 film with a thickness of 10 nm. This TCTA film was used as a hole transport layer. Furthermore, the following compound (H) having a film thickness of 30 nm was deposited on the TCTA film as a host material to form a light emitting layer, and at the same time, the above metal complex compound (B25) as a phosphorescent Ir metal complex dopant. The concentration of the metal complex compound (B25) in the light emitting layer was 7.5% by weight, and this film functions as the light emitting layer, and the following BAlq having a thickness of 25 nm was formed on this film. This BAlq film functions as an electron transport layer, and then the following Alq film having a thickness of 5 nm is formed on this film.This Alq film functions as an electron injection layer. Vapor deposition was performed to a thickness of 1 nm, and then aluminum was deposited to a thickness of 150 nm, and the Al / LiF functions as a cathode.
When the obtained device was sealed and subjected to an energization test, the CIE chromaticity (0.17, 0.30) was obtained at a voltage of 6.4 V, a current density of 0.96 mA / cm ² , and an emission luminance of 100 cd / m ^2. ) Was obtained, and the luminous efficiency was 10.4 cd / A.

Example 2
A device was fabricated in the same manner as in Example 1 except that (B35) was used instead of (B25) as the dopant. When this device was subjected to an energization test, blue-green light emission with a voltage of 6.2 V, a current density of 0.52 mA / cm ² , an emission luminance of 106 cd / m ² , and a CIE chromaticity (0.16, 0.30) Was obtained, and the light emission efficiency was 20 cd / A.

Comparative Example 1
A device was produced in the same manner as in Example 1 except that Compound D was used instead of (B35) as a dopant. When this device was subjected to an energization test, blue-green light emission with a voltage of 6.4 V, a current density of 1.08 mA / cm ² , an emission luminance of 102 cd / m ² , and CIE chromaticity (0.18, 0.35) And the luminous efficiency was 9.4 cd / A.

Table 1 shows the emission wavelengths of the compounds (B25), (B35) and (Compound D) in solution.

  By introducing a substituent into the element adjacent to the carbon bonded to the Ir metal, a deep color can be achieved and the efficiency as an EL element is improved.

As described above in detail, the organic EL device using the metal complex compound of the present invention has high luminous efficiency and can be applied to fields such as various display devices, displays, backlights, illumination light sources, signs, signboards, and interiors. Particularly, it is suitable as a display element for a color display.

Claims (20)

A metal complex compound represented by the following general formula (1).
(L ₁ ) _m M (L ₂ ) _n (1)
[In General Formula (1), M is a metal atom of iridium (Ir), platinum (Pt), rhodium (Rh) or palladium (Pd), and L ₁ and L ₂ are bidentate ligands different from each other. is there. m is an integer of 1 to 3, n is an integer of 0 to 1, and m + n is an integer of 2 or 3.
The partial structure (L ₁ ) _m M is represented by the general formula (2) or (3).

{In General Formulas (2) and (3), N represents a nitrogen atom, and Q represents a nitrogen atom or a carbon atom. The A ring is an aryl group or cycloalkenyl group having 4 to 40 nuclear carbon atoms which may have a substituent, and the B ring has 3 to 3 nuclear atoms containing a nitrogen atom which may have a substituent. 40 aromatic heterocyclic groups, the A ring and the B ring are bonded by a covalent bond via a carbon or nitrogen atom. R ₁ and R ₄ are each independently an alkyl group having 1 to 30 carbon atoms which may have a substituent, a halogenated alkyl group having 2 to 30 carbon atoms which may have a substituent, or a substituent. An aromatic heterocyclic group having 3 to 30 nuclear atoms, an aryl group having 6 to 30 nuclear carbon atoms which may have a substituent, and an alkyl group having 7 to 40 carbon atoms which may have a substituent An aralkyl group, an optionally substituted alkenyl group having 2 to 30 carbon atoms, an optionally substituted arylamino group having 6 to 40 carbon atoms, and an optionally substituted carbon atom having 1 to 1 carbon atoms 40 alkylamino groups, an optionally substituted alkyl silyl group having 3 to 30 carbon atoms, an optionally substituted aryl silyl group having 6 to 30 carbon atoms, a thiocyano group, a cyano group, a nitro group, -S (R) O ₂ group, -S (R) O (R is a substituted group), carbon atoms which may have a substituent 1 to 3 Alkoxy group or a substituent a good ester group having 1 to 30 carbon atoms which may have a chlorine atom, selected from bromine and iodine atoms. R ₂ is selected from the same group as the above R ₁ and R ₄ , a hydrogen atom, a fluorine atom and a trifluoromethyl group. R ₃ is an optionally substituted alkyl group having 1 to 30 carbon atoms, an optionally substituted halogenated alkyl group having 2 to 30 carbon atoms, and an optionally substituted nucleus atom. An aromatic heterocyclic group having 3 to 30 carbon atoms, an aryl group having 6 to 30 nuclear carbon atoms which may have a substituent, an aralkyl group having 7 to 40 carbon atoms which may have a substituent, and a substituent; An optionally substituted alkenyl group having 2 to 30 carbon atoms, an arylamino group having 6 to 40 carbon atoms which may have a substituent, an alkylamino group having 1 to 40 carbon atoms which may have a substituent, and a substituent good number 3-30 alkylsilyl group carbon atoms which may have a group, aryl silyl group having 6 to 30 carbon atoms which may have a substituent group, thiocyano group, a cyano group, a nitro group, -S (R) O ₂ Group, -S (R) O (R is a substituent), an optionally substituted alkoxy group having 1 to 30 carbon atoms or a substituent It is selected from a C1-30 ester group which may have a group and a hydrogen atom. R ₂ and R ₃ may be bonded to each other to form a cyclic structure. R ₁ and R ₄ are each bonded to a carbon atom adjacent to the carbon atom bonded to M. }] The metal complex compound according to claim 1, wherein the partial structure (L ₁ ) _m M in the general formula (1) is represented by any one of the following general formulas (4) to (6).

(In the formula, M and m are the same as defined above. R ₅ , R ₁₀ and R ₁₄ are each independently selected from the same groups as R ₁ and R ₄ in formulas (2) and (3)). R _{6 to} R ₉ , R _{11 to} R ₁₃ , R ₁₅ and R ₁₇ are each independently selected from the same group as R ₂ in the general formula (2), and R ₁₆ is R in the general formula (2). R ₆ and R ₇ , R ₇ and R ₈ , R ₈ and R ₉ , R ₁₁ and R ₁₂ , R ₁₂ and R ₁₃ , R ₁₅ and R _16, and R ₁₆ and R ₁₇ are selected from the same groups as _3. Each may be bonded to each other to form a cyclic structure, and R ₅ , R ₁₀ and R ₁₄ are each bonded to the carbon atom adjacent to the carbon atom bonded to M.) The metal complex compound according to claim 1, wherein the partial structure (L ₁ ) _m M in the general formula (1) is a partial structure represented by any one of the following general formulas (7) to (9).

(In the formula, M and m are the same as defined above. R ₁₈ , R ₂₅ and R ₃₁ are each independently selected from the same groups as R ₁ and R ₄ in formulas (2) and (3)). _{.R 19 ~R 24, R 26 ~R} 30, R 32 ~R 34 and R ₃₆ are each independently, .R ₃₅ selected from the same group as R ₂ in the general formula (2) has the general formula (2 ) and .R ₂₀ and R _21, R ₂₁ and R _22, R ₂₂ and R _23, R ₂₃ and R _24, R ₂₇ and R _28, R ₂₈ and R _29, R ₂₉ selected from the same group as R ₃ in R ₃₀ , R ₃₃ and R ₃₄ , R ₃₄ and R ₃₅ and R ₃₅ and R ₃₆ may be bonded to each other to form a cyclic structure, and R ₁₈ , R ₂₅ and R ₃₁ are each bonded to M. Bonds to the carbon atom next to the carbon atom.) The metal complex compound according to claim 1, wherein the partial structure (L ₁ ) _m M in the general formula (1) is represented by the following general formula (10) or (11).

(In the formula, all of M, m, N, Q, A ring and B ring are the same as those in formulas (2) and (3). R _{1 ′} and R _{4 ′} are each independently equation (2) and (3) .R 2 selected from the same group and a halogen atom and R ₁ and R ₄ in _'is .R 3 which selected from the same group as R ₂ in the general formula _(2)' is generally .R ₅₉ and R ₆₀ are selected from the same group as R ₃ in formula (2) are each independently a general formula (2) and the same group as R ₁ and R ₄ in (3), a fluorine atom and trifluoromethyl R ₅₉ and R ₆₀ are each bonded to the carbon atom adjacent to the carbon atom bonded to R _{1 ′} and R _{4 ′} ) The metal complex compound according to claim 4, wherein the partial structure (L ₁ ) _m M in the general formula (1) is represented by any one of the following general formulas (12) to (14).

(In the formula, M and m are the same as defined above. R _{5 ′} , R _{10 ′} and R _{14 ′} are each independently the same groups as R ₁ and R ₄ in the general formulas (2) and (3)). selected from _{.R 6 '~R 9', R} 11 '~R 13', .R R 15 ' and R _17' are each independently selected from the same group as R ₂ in the general formula (2) _{16 '} Is selected from the same group as R ₃ in the general formula (2) R _{61 to} R ₆₃ are each independently selected from the same groups as R ₅₉ and R ₆₀ in the general formulas (10) and (11). R _{6 ′} and R _{7 ′} , R _{7 ′} and R _{8 ′} , R _{8 ′} and R _{9 ′} , R _{11 ′} and R _{12 ′} , R _{12 ′} and R _{13 ′} , R _{15 ′} and R _{16 ′} and R _{16 ′} and R _{17 ′} may be bonded to each other to form a cyclic structure, and R _{5 ′} , R _{10 ′} and R _{14 ′} are each bonded to a carbon atom adjacent to the carbon atom bonded to M. ) The metal complex compound according to claim 4, wherein the partial structure (L ₁ ) _m M in the general formula (1) is a partial structure represented by any one of the following general formulas (15) to (17).

Wherein M and m are the same as defined above. R _{18 ′} , R _{25 ′} and R _{31 ′} are each independently the same group as R ₁ and R ₄ in the general formulas (2) and (3). R _{20 ′ to} R _{24 ′} , R _{27 ′ to} R _{30 ′} , R _{33 ′} , R _{34 ′} and R _{36 ′} are each independently selected from the same groups as R ₂ in the general formula (2) R _{35 ′} is selected from the same group as R ₃ in the general formula (2) R _{19 ′} , R _{26 ′} and R _{32 ′} are each independently R in the general formulas (10) and (11). ₅₉ and R ₆₀ are selected from the same group: R _{20 ′} and R _{21 ′} , R _{21 ′} and R _{22 ′} , R _{22 ′} and R _{23 ′} , R _{23 ′} and R _{24 ′} , R _{27 ′} and R _{28 ′.} , R _{28 ′} and R _{29 ′} , R _{29 ′} and R _{30 ′} , R _{33 ′} and R _{34 ′} , R _{34 ′} and R _{35 ′} and R _{35 ′} and R _{36 ′} are bonded to each other to form a cyclic structure. R _{18 ′} , R _{25 ′} and R _{31 ′} may each be a carbon atom bonded to M. To the next carbon atom.) The metal complex compound according to claim 1, wherein the partial structure M (L ₂ ) _n in the general formula (1) is represented by any one of the following general formulas (18) to (22).

(In the formula, M and n are the same as defined above. R _{37 to} R ₅₈ are each independently selected from the same groups as R ₂ in formula (2). Adjacent of R _{37 to} R _58. Each may be bonded together to form a ring structure.)   The metal complex compound according to claim 1, wherein in general formula (1), m = 3, n = 0, and M is Ir.   The metal complex compound according to any one of claims 1 to 7, wherein in the general formula (1), m = 2, n = 1, and M is Ir.   The metal complex compound according to any one of claims 1 to 6, wherein m = 2, n = 0 and M is Pt in the general formula (1). In the general formula (1), L ₁ is a bidentate ligand of any one of the general formulas (15) to (17), L ₂ is a bidentate ligand of the general formula (18), The metal complex compound according to claim 1, wherein M is Ir, m and n are integers of 1 to 2, and m + n = 3. In the general formula (1), L ₁ is a bidentate ligand of any one of the general formulas (15) to (17), L ₂ is a bidentate ligand of the general formula (19), The metal complex compound according to claim 1, wherein M is Ir, m and n are integers of 1 to 2, and m + n = 3. In the general formula (1), L ₁ is a bidentate ligand of any one of the general formulas (15) to (17), L ₂ is a bidentate ligand of the general formula (20), The metal complex compound according to claim 1, wherein M is Ir, m and n are integers of 1 to 2, and m + n = 3. In the general formula (1), L ₁ is a bidentate ligand of any one of the general formulas (15) to (17), L ₂ is a bidentate ligand of the general formula (21), The metal complex compound according to claim 1, wherein M is Ir, m and n are integers of 1 to 2, and m + n = 3. In the general formula (1), L ₁ is a bidentate ligand of any one of the general formulas (15) to (17), L ₂ is a bidentate ligand of the general formula (22), The metal complex compound according to claim 1, wherein M is Ir, m and n are integers of 1 to 2, and m + n = 3.   In the organic electroluminescent element in which the organic thin film layer which consists of a single layer or multiple layers which has an at least light emitting layer between the anode and the cathode is pinched | interposed, at least 1 layer of this organic thin film layer is in any one of Claims 1-15. The organic electroluminescent element containing the metal complex compound of this.   The organic electroluminescent element of Claim 16 in which the said light emitting layer contains the metal complex compound in any one of Claims 1-15 as a luminescent material.   The organic electroluminescent element of Claim 16 in which the said light emitting layer contains the metal complex compound in any one of Claims 1-15 as a dopant.   An electron injection layer and / or an electron transport layer is provided between the light emitting layer and the cathode, and the electron injection layer and / or the electron transport layer contains a π electron deficient nitrogen-containing heterocyclic derivative as a main component. 16. The organic electroluminescence device according to 16. The organic electroluminescent element according to claim 16, wherein a reducing dopant is added to an interface region between a cathode and the organic thin film layer.