JP2008214306A - Electron transport material and organic electroluminescent element using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electron transport material contributing to the lowering of the driving voltage of an organic EL element, the elongation of the life, etc., and to provide an organic EL element utilizing the electron transport material. <P>SOLUTION: The invention relates to a compound represented by formula (1), and an organic EL element using the compound. In the formula, G is an n-valent linking group; n is an integer of 2-4; R<SP>1</SP>to R<SP>4</SP>are each independently a hydrogen atom, a mono-valent group or a free atomic valence linking to G; R<SP>5</SP>to R<SP>8</SP>are each independently a hydrogen atom or a mono-valent group; one of R<SP>1</SP>to R<SP>4</SP>is a free atomic valence linking to G; and n 4,3'-bipyridyl groups are the same or different. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a novel electron transporting material having a 4,3′-bipyridyl group, an organic electroluminescence device using the electron transporting material (hereinafter sometimes abbreviated as an organic EL device or simply a device), and the like.

In recent years, organic EL elements have attracted attention as next-generation full-color flat panel displays, and active research has been conducted. In order to promote the practical use of organic EL elements, it is indispensable to reduce the drive voltage and extend the life of the elements, and new electron transport materials have been developed to achieve these. JP 2003-123983 A (Patent Document 1) describes that an organic EL device can be driven at a low voltage by using a phenanthroline derivative as an electron transporting material, and is similar to phenanthroline. Similarly, it is described that an organic EL device can be driven at a low voltage by using a 2,2′-bipyridyl compound as a body as an electron transport material. However, the element characteristics (driving voltage, light emission efficiency, etc.) reported in the examples of this document are only relative values based on comparative examples, and no actual measurement values that can be judged as practical values are described. Alternatively, example of using 2,2'-bipyridyl compound to the electron-transporting ^{material, Proceedings of the 10 th International Workshop} on Inorganic and Organic Electroluminescence (: non-patent document 1), JP 2002-158093 JP (: Patent Document 2) and Japanese Patent Application Laid-Open No. 11-514143 (Patent Document 3). The 2,2′-bipyridyl compound described in Non-Patent Document 1 has a low glass transition temperature (hereinafter abbreviated as Tg) and is not practical. The 2,2′-bipyridyl compound described in Patent Document 3 can drive an organic EL device at a relatively low voltage, but further reduction in voltage is desired for practical use. Patent Document 3 does not disclose a specific compound.
JP 2003-123983 A JP 2002-158093 A Japanese National Patent Publication No. 11-514143 Proceedings of the 10th International Workshop on Inorganic and Organic Electroluminescence

The present invention has been made in view of the problems of such conventional techniques. It is an object of the present invention to provide an electron transport material that contributes to reduction in driving voltage and long life of an organic EL element. Furthermore, this invention makes it a subject to provide the organic EL element using this electron transport material.

As a result of intensive studies, the present inventors have obtained an organic EL device that can be driven with high brightness, long life, and low voltage by using a compound having 4,3′-bipyridyl for the electron transport layer of the organic EL device. Based on this finding, the present invention has been completed.
Said subject is solved by each item shown below.

式中、Ｇはｎ価の連結基であり、ｎは２〜４の整数であり；
Ｒ^１〜Ｒ^４は独立して水素、１価の基またはＧに結合する遊離原子価であり、Ｒ^５〜Ｒ^８は独立して水素または１価の基であるが、Ｒ^１〜Ｒ^４の１つはＧに結合する遊離原子価であり；そして、ｎ個の４，３’−ビピリジル基は同一でもよく、異なっていてもよい。

［２］Ｒ^１〜Ｒ^４の１つがＧに結合する遊離原子価であり、それ以外が水素であり、Ｒ^５〜Ｒ⁸が水素である、前記［１］項に記載の化合物。 [1] A compound represented by the following formula (1).

Wherein G is an n-valent linking group and n is an integer of 2 to 4;
R ^{1 to} R ⁴ are independently hydrogen, a monovalent group or a free valence bonded to G, and R ^{5 to} R ⁸ are independently hydrogen or a monovalent group, but R ^{1 to} R ⁴ Is the free valence attached to G; and the n 4,3′-bipyridyl groups may be the same or different.

[2] The compound according to [1], wherein one of R ^{1 to} R ⁴ is a free valence bonded to G, the other is hydrogen, and R ^{5 to} R ⁸ are hydrogen.

式中、Ｇは下記の式（Ｇ１）〜（Ｇ３）で表される基の群から選択される１つであり；Ｒ^９〜Ｒ^１２の１つはＧに結合する遊離原子価であり、それ以外は水素であり；そして、Ｒ^１３〜Ｒ^１６の１つはＧに結合する遊離原子価であり、それ以外は水素である。

式中、Ｇ^１は独立して、下記の式（Ａ−１）〜（Ａ−２１）および式（Ｂ−１）〜（Ｂ−４０）で表される化合物の群から選択される１つから誘導される２価の基である。

上記の式中、Ｒは独立して水素、炭素数１〜８のアルキル、炭素数３〜１０のシクロアルキル、または炭素数６〜２０のアリールであり；式（Ａ−１）〜（Ａ−２１）および式（Ｂ−１）〜（Ｂ−４０）で表される化合物から誘導される２価の基は、遊離原子価を持つ原子以外の位置に置換基を有していてもよい。 [3] The compound according to item [2], represented by the following formula (2).

In the formula, G is one selected from the group of groups represented by the following formulas (G1) to (G3); one of R ^{9 to} R ¹² is a free valence bonded to G; The other is hydrogen; and one of R ¹³ -R ¹⁶ is the free valence bonded to G, the other is hydrogen.

In the formula, G ¹ is independently one selected from the group of compounds represented by the following formulas (A-1) to (A-21) and formulas (B-1) to (B-40) Is a divalent group derived from

In the above formula, R is independently hydrogen, alkyl having 1 to 8 carbons, cycloalkyl having 3 to 10 carbons, or aryl having 6 to 20 carbons; formulas (A-1) to (A- 21) and the divalent group derived from the compounds represented by formulas (B-1) to (B-40) may have a substituent at a position other than the atom having a free valence.

式中、Ｇの定義は前記［３］項に記載の式（２）におけるＧと同じである。

［５］Ｇが前記の式（Ｇ１）で表される連結基であり、式（Ｇ１）中Ｇ^１が前記の式（Ａ−１）〜（Ａ−２１）で表される化合物の群から選択される１つから誘導される２価の基である、前記［４］項に記載の化合物。

［６］Ｇが前記の式（Ｇ１）で表される連結基であり、式（Ｇ１）中Ｇ^１が前記の式（Ａ−１）〜（Ａ−４）で表される化合物の群から選択される１つから誘導される２価の基である、前記［４］項に記載の化合物。

［７］Ｇが前記の式（Ｇ１）で表される連結基であり、式（Ｇ１）中Ｇ^１が下記の式（Ｃ−１）〜（Ｃ−１０）で表される２価の基の群から選択される１つである、前記［４］項に記載の化合物。

式中、Ｒは独立して水素、メチル、エチル、へキシル、シクロヘキシル、フェニル、１−ナフチルまたは２−ナフチルであり；式（Ｃ−１）〜（Ｃ−１０）で表される２価の基は、遊離原子価をもつ原子以外の位置に置換基を有していてもよい。

［８］Ｇが前記の式（Ｇ２）で表される連結基であり、式（Ｇ２）中、Ｇ^１が前記の式（Ａ−１）〜（Ａ−２１）および式（Ｂ−１）〜（Ｂ−４０）で表される化合物の群から選択される１つから誘導される同一の２価の基である、前記［４］項に記載の化合物。

［９］Ｇが前記の式（Ｇ２）で表される連結基であり、式（Ｇ２）中、Ｇ^１が前記の式（Ｃ−１）〜（Ｃ−６）で表される２価の基の群から選択される同一の基である、前記［４］項に記載の化合物。

［１０］Ｇが下記の式（Ｇ３−１）〜（Ｇ３−３）で表される基の群から選択される１つである、前記［４］項に記載の化合物。

式中、Ｇ^１Ａは独立して、前記の式（Ａ−１）〜（Ａ−２１）で表される化合物の群から選択される１つから誘導される２価の基であり；Ｇ^１Ｂは独立して、前記の記載の式（Ｂ−１）〜（Ｂ−４０）で表される化合物の群から選択される１つから誘導される２価の基である。

［１１］Ｇが式（Ｇ３−２）で表される連結基であり；Ｇ^１Ａが前記の式（Ｃ−１）〜（Ｃ−６）で表される２価の基の群から選択される同一の基であり、Ｇ^１Ｂが下記の式（Ｄ−１）〜（Ｄ−１０）で表される２価の基の群から選択される１つである、前記［１０］項に記載の化合物。

式中、Ｒは独立して水素、メチル、エチル、へキシル、シクロヘキシル、フェニル、１−ナフチルまたは２−ナフチルであり；式（Ｄ−１）〜（Ｄ−１０）で表される２価の基は、遊離原子価をもつ原子以外の位置に置換基を有していてもよい。

［１２］Ｇが式（Ｇ３−３）で表される連結基であり；Ｇ^１Ａが前記の式（Ｃ−１）〜（Ｃ−６）で表される２価の基の群から選択される１つであり、Ｇ^１Ｂが前記の式（Ｄ−１）〜（Ｄ−１０）で表される２価の基の群から選択される同一の基である、前記［１０］項に記載の化合物。

［１３］Ｇが下記の式（Ｇ３−４）で表される連結基である、前記［１０］項に記載の化合物。

式中、Ｇ^１Ｂ１は前記の式（Ｄ−１）〜（Ｄ−５）で表される２価の基の群から選択される１つであり、Ｇ^１Ｂ２は前記の式（Ｄ−１）〜（Ｄ−１０）で表される２価の基の群から選択される同一の基である。 [4] The compound according to [3], which is represented by the following formula (2-1).

In the formula, the definition of G is the same as G in the formula (2) described in the item [3].

[5] a linking group G is represented by the formula (G1), from the group of compounds formula (G1) Medium ^{G 1} is represented by the formula (A-1) ~ (A -21) The compound according to [4] above, which is a divalent group derived from one selected.

[6] is a linking group G is represented by the formula (G1), from the group of compounds represented by formula (G1) Medium ^{G 1} is the formula (A-1) ~ (A -4) The compound according to [4] above, which is a divalent group derived from one selected.

[7] G is a linking group represented by the above formula (G1), and G ^{1 in} the formula (G1) is a divalent group represented by the following formulas (C-1) to (C-10): The compound according to [4] above, which is one selected from the group of

In the formula, R is independently hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl or 2-naphthyl; a divalent group represented by formulas (C-1) to (C-10) The group may have a substituent at a position other than the atom having a free valence.

[8] G is a linking group represented by the formula (G2), the formula (G2) in, ^{G 1} is the formula (A-1) ~ (A -21) and formula (B-1) The compound according to [4] above, which is the same divalent group derived from one selected from the group of compounds represented by: (B-40).

[9] G is a linking group represented by the above formula (G2), and in formula (G2), G ¹ is a divalent group represented by the above formulas (C-1) to (C-6). The compound according to item [4], which is the same group selected from the group of groups.

[10] The compound according to [4], wherein G is one selected from the group of groups represented by the following formulas (G3-1) to (G3-3).

In the formula, G ^1A is independently a divalent group derived from one selected from the group of compounds represented by formulas (A-1) to (A-21); G ^1B Is independently a divalent group derived from one selected from the group of compounds represented by formulas (B-1) to (B-40) described above.

[11] G is a linking group represented by the formula (G3-2); G ^1A is selected from the group of divalent groups represented by the formulas (C-1) to (C-6). The same group, and G ^1B is one selected from the group of divalent groups represented by the following formulas (D-1) to (D-10): Compound.

In the formula, R is independently hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl or 2-naphthyl; a divalent group represented by formulas (D-1) to (D-10) The group may have a substituent at a position other than the atom having a free valence.

[12] G is a linking group represented by the formula (G3-3); G ^1A is selected from the group of divalent groups represented by the formulas (C-1) to (C-6). And G ^1B is the same group selected from the group of divalent groups represented by the formulas (D-1) to (D-10). Compound.

[13] The compound according to [10], wherein G is a linking group represented by the following formula (G3-4).

In the formula, G ^1B1 is one selected from the group of divalent groups represented by the formulas (D-1) to (D-5), and G ^1B2 is the formula (D-1). It is the same group selected from the group of the bivalent group represented by-(D-10).

式中、Ｇの定義は前記［３］項に記載の式（２）におけるＧと同じである。

［１５］Ｇが前記の式（Ｇ１）で表される連結基であり、式（Ｇ１）中Ｇ^１が前記の式（Ａ−１）〜（Ａ−２１）で表される化合物の群から選択される１つから誘導される２価の基である、前記［１４］項に記載の化合物。

［１６］Ｇが前記の式（Ｇ１）で表される連結基であり、式（Ｇ１）中Ｇ^１が前記の式（Ａ−１）〜（Ａ−４）で表される化合物の群から選択される１つから誘導される２価の基である、前記［１４］項に記載の化合物。

［１７］Ｇが前記の式（Ｇ１）で表される連結基であり、式（Ｇ１）中Ｇ^１が前記の式（Ｃ−１）〜（Ｃ−１０）で表される２価の基の群から選択される１つである、前記［１４］項に記載の化合物。

［１８］Ｇが式（Ｇ２）で表される連結基であり、式（Ｇ２）中Ｇ^１が前記の式（Ａ−１）〜（Ａ−２１）および式（Ｂ−１）〜（Ｂ−４０）で表される化合物の群から選択される１つから誘導される同一の２価の基である、前記［１４］項に記載の化合物。

［１９］Ｇが前記の式（Ｇ２）で表される連結基であり、式（Ｇ２）中Ｇ^１が前記の式（Ｃ−１）〜（Ｃ−６）で表される２価の基の群から選択される同一の基である、前記［１４］項に記載の化合物。

［２０］Ｇが下記の式（Ｇ３−１）〜（Ｇ３−３）で表される基の群から選択される１つである、前記［１４］項に記載の化合物。

式中、Ｇ^１Ａは独立して、前記の式（Ａ−１）〜（Ａ−２１）で表される化合物の群から選択される１つから誘導される２価の基であり；Ｇ^１Ｂは独立して、前記の式（Ｂ−１）〜（Ｂ−４０）で表される化合物の群から選択される１つから誘導される２価の基である。

［２１］Ｇが式（Ｇ３−２）で表される連結基であり；Ｇ^１Ａが前記の式（Ｃ−１）〜（Ｃ−６）で表される２価の基の群から選択される同一の基であり、Ｇ^１Ｂが前記の式（Ｄ−１）〜（Ｄ−１０）で表される２価の基の群から選択される１つである、前記［２０］項に記載の化合物。

［２２］Ｇが式（Ｇ３−３）で表される連結基であり；Ｇ^１Ａが前記の式（Ｃ−１）〜（Ｃ−６）で表される２価の基の群から選択される１つであり、Ｇ^１Ｂが前記の式（Ｄ−１）〜（Ｄ−１０）で表される２価の基の群から選択される同一の基である、前記［２０］項に記載の化合物。

［２３］Ｇが下記の式（Ｇ３−４）で表される連結基である、前記［２０］項に記載の化合物。

式中、Ｇ^１Ｂ１は前記の式（Ｄ−１）〜（Ｄ−５）で表される２価の基の群から選択される１つであり、Ｇ^１Ｂ２は前記の式（Ｄ−１）〜（Ｄ−１０）で表される２価の基の群から選択される同一の基である。 [14] The compound according to item [3], represented by the following formula (2-2).

In the formula, the definition of G is the same as G in the formula (2) described in the item [3].

[15] a linking group G is represented by the formula (G1), from the group of compounds formula (G1) Medium ^{G 1} is represented by the formula (A-1) ~ (A -21) The compound according to item [14], which is a divalent group derived from one selected.

[16] a linking group G is represented by the formula (G1), from the group of compounds represented by formula (G1) Medium ^{G 1} is the formula (A-1) ~ (A -4) The compound according to item [14], which is a divalent group derived from one selected.

[17] G is a linking group represented by the formula (G1), and G ^{1 in} the formula (G1) is a divalent group represented by the formulas (C-1) to (C-10). The compound according to the above item [14], which is one selected from the group of [14].

[18] G is a linking group represented by the formula (G2), and G ^{1 in} the formula (G2) is the formula (A-1) to (A-21) and the formula (B-1) to (B The compound according to [14] above, which is the same divalent group derived from one selected from the group of compounds represented by -40).

[19] G is a linking group represented by the formula (G2), and G ^{1 in} the formula (G2) is a divalent group represented by the formulas (C-1) to (C-6). The compound according to the above item [14], which is the same group selected from the group of [14].

[20] The compound according to item [14], wherein G is one selected from the group of groups represented by the following formulas (G3-1) to (G3-3).

In the formula, G ^1A is independently a divalent group derived from one selected from the group of compounds represented by formulas (A-1) to (A-21); G ^1B Is independently a divalent group derived from one selected from the group of compounds represented by formulas (B-1) to (B-40).

[21] G is a linking group represented by the formula (G3-2); G ^1A is selected from the group of divalent groups represented by the formulas (C-1) to (C-6). The above-mentioned [20], wherein G ^1B is one selected from the group of divalent groups represented by the formulas (D-1) to (D-10). Compound.

[22] G is a linking group represented by the formula (G3-3); G ^1A is selected from the group of divalent groups represented by the formulas (C-1) to (C-6). And G ^1B is the same group selected from the group of divalent groups represented by the formulas (D-1) to (D-10). Compound.

[23] The compound according to [20], wherein G is a linking group represented by the following formula (G3-4).

In the formula, G ^1B1 is one selected from the group of divalent groups represented by the formulas (D-1) to (D-5), and G ^1B2 is the formula (D-1). It is the same group selected from the group of the bivalent group represented by-(D-10).

式中、Ｇの定義は前記［３］項に記載の式（２）におけるＧと同じである。

［２５］Ｇが前記の式（Ｇ１）で表される連結基であり、式（Ｇ１）中Ｇ^１が前記の式（Ａ−１）〜（Ａ−２１）で表される化合物の群から選択される１つから誘導される２価の基である、前記［２４］項に記載の化合物。

［２６］Ｇが前記の式（Ｇ１）で表される連結基であり、式（Ｇ１）中Ｇ^１が前記の式（Ｃ−１）〜（Ｃ−１０）で表される２価の基の群から選択される１つである、前記［２４］項に記載の化合物。
[24] The compound according to item [3], represented by the following formula (2-3).

In the formula, the definition of G is the same as G in the formula (2) described in the item [3].

[25] G is a linking group represented by the above formula (G1), and G ^{1 in} the formula (G1) is selected from the group of compounds represented by the above formulas (A-1) to (A-21). The compound according to the above [24], which is a divalent group derived from one selected.

[26] G is a linking group represented by the formula (G1), and G ^{1 in} the formula (G1) is a divalent group represented by the formulas (C-1) to (C-10). The compound according to [24] above, which is one selected from the group of

式中、Ｇは下記の式（Ｇ４）または（Ｇ５）で表される基であり；Ｒ^１７〜Ｒ^２０の１つはＧに結合する遊離原子価であり、それ以外は水素であり；Ｒ^２１〜Ｒ^２４の１つはＧに結合する遊離原子価であり、それ以外は水素であり；Ｒ^２５〜Ｒ^２８の１つはＧに結合する遊離原子価であり、それ以外は水素である。

式中、Ｇ^１は独立して、前記の式（Ａ−１）〜（Ａ−２１）および式（Ｂ−１）〜（Ｂ−４０）で表される化合物の群から選択される１つから誘導される２価の基であり；Ｇ^２Ａは、下記の式（Ｅ−１）〜（Ｅ−９）で表される３価の基の群から選択される１つであり、Ｇ^２Ｂはホウ素、ホスホリル基、または式（Ｅ−１）〜（Ｅ−９）で表される３価の基の群から選択される１つである。

［２８］Ｇが式（Ｇ５）で表される連結基であり、式（Ｇ５）においてＧ^１が同一である、前記[２７]項に記載の化合物。 [27] The compound according to item [2], represented by the following formula (3):

In the formula, G is a group represented by the following formula (G4) or (G5); one of R ^{17 to} R ²⁰ is a free valence bonded to G, and the other is hydrogen; ^{One of 21 to} R ²⁴ is a free valence bonded to G and the other is hydrogen; one of R ^{25 to} R ²⁸ is a free valence bonded to G and the other is hydrogen .

In the formula, G ¹ is independently one selected from the group of compounds represented by formulas (A-1) to (A-21) and formulas (B-1) to (B-40). G ^2A is one selected from the group of trivalent groups represented by the following formulas (E-1) to (E-9), and G ^2B Is one selected from the group of boron, phosphoryl groups, or trivalent groups represented by formulas (E-1) to (E-9).

[28] The compound according to [27], wherein G is a linking group represented by formula (G5), and G ¹ is the same in formula (G5).

式中、Ｇは下記の式（Ｇ６）または（Ｇ７）で表される基であり；Ｒ^２９〜Ｒ^３２の１つはＧに結合する遊離原子価であり、それ以外は水素であり；Ｒ^３３〜Ｒ^３６の１つはＧに結合する遊離原子価であり、それ以外は水素であり；Ｒ^３７〜Ｒ^４０の１つはＧに結合する遊離原子価であり、それ以外は水素であり；Ｒ^４１〜Ｒ^４４の１つはＧに結合する遊離原子価であり、それ以外は水素である。

式中、Ｇ^１は独立して、前記の式（Ａ−１）〜（Ａ−２１）および式（Ｂ−１）〜（Ｂ−４０）で表される化合物の群から選択される１つから誘導される２価の基であり；Ｇ^３Ａは、下記の式（Ｆ−１）〜（Ｆ−８）で表される４価の基の群から選択される１つであり；Ｇ^３Ｂは炭素、ケイ素、または式（Ｆ−１）〜（Ｆ−８）で表される４価の基の群から選択される１つである。

［３０］Ｇが式（Ｇ７）で表される連結基であり、式（Ｇ７）においてＧ^１が同一である、前記[２９]項に記載の化合物。 [29] The compound according to item [2], represented by the following formula (4):

In the formula, G is a group represented by the following formula (G6) or (G7); one of R ^{29 to} R ³² is a free valence bonded to G, and the other is hydrogen; ^{One of 33 to} R ³⁶ is a free valence bonded to G and the other is hydrogen; one of R ^{37 to} R ⁴⁰ is a free valence bonded to G and the other is hydrogen One of R ^{41 to} R ⁴⁴ is a free valence bonded to G, and the other is hydrogen.

In the formula, G ¹ is independently one selected from the group of compounds represented by formulas (A-1) to (A-21) and formulas (B-1) to (B-40). G ^3A is one selected from the group of tetravalent groups represented by the following formulas (F-1) to (F-8); G ^3B Is one selected from carbon, silicon, or a group of tetravalent groups represented by formulas (F-1) to (F-8).

[30] The compound according to [29], wherein G is a linking group represented by formula (G7), and G ¹ is the same in formula (G7).

上記の式中、Ｒ^４５は水素、メチル、ｔ−ブチル、シクロヘキシル、フェニル、ナフチル、ビフェニリルまたはテルフェニリルである。

［３２］Ｇが前記の式（５）で表される、前記[４]項に記載の化合物。

［３３］Ｇが前記の式（５）で表される、前記[１４]項に記載の化合物。 [31] The compound according to [3], wherein G is represented by the following formula (5).

In the above formula, R ⁴⁵ is hydrogen, methyl, t-butyl, cyclohexyl, phenyl, naphthyl, biphenylyl or terphenylyl.

[32] The compound according to [4], wherein G is represented by the formula (5).

[33] The compound according to [14], wherein G is represented by the formula (5).

上記の式中、Ｒ^４６〜Ｒ^４９は独立して水素、メチル、ｔ−ブチル、シクロヘキシル、フェニル、ナフチル、ビフェニリルまたはテルフェニリルである。

［３５］Ｇが前記の式（６）で表される、前記［４］項に記載の化合物。

［３６］Ｇが前記の式（６）で表される、前記［１４］項に記載の化合物。 [34] The compound according to [3], wherein G is represented by the following formula (6).

In the above formula, R ^{46 to} R ⁴⁹ are independently hydrogen, methyl, t-butyl, cyclohexyl, phenyl, naphthyl, biphenylyl or terphenylyl.

[35] The compound according to [4], wherein G is represented by the formula (6).

[36] The compound according to [14], wherein G is represented by the formula (6).

上記の式中、Ｒ^５０およびＲ^５１は独立して水素、メチル、ｔ−ブチル、シクロヘキシル、フェニル、ナフチル、ビフェニリルまたはテルフェニリルである。

［３８］Ｇが前記の式（７）で表される、前記［４］項に記載の化合物。

［３９］Ｇが前記の式（７）で表される、前記［１４］項に記載の化合物。 [37] The compound according to [3], wherein G is represented by the following formula (7).

In the above formula, R ⁵⁰ and R ⁵¹ are independently hydrogen, methyl, t-butyl, cyclohexyl, phenyl, naphthyl, biphenylyl or terphenylyl.

[38] The compound according to [4], wherein G is represented by the formula (7).

[39] The compound according to [14], wherein G is represented by the formula (7).

［４１］Ｇが前記の式（８）で表される、前記［４］項に記載の化合物。

［４２］Ｇが前記の式（８）で表される、前記［１４］項に記載の化合物。 [40] The compound according to [3], wherein G is represented by the following formula (8).

[41] The compound according to [4], wherein G is represented by the formula (8).

[42] The compound according to [14], wherein G is represented by the formula (8).

[43] An organic electroluminescent device comprising the compound according to any one of [1] to [42].

[44] An organic electroluminescent device having at least a hole transport layer, a light-emitting layer, and an electron transport layer sandwiched between an anode and a cathode on the substrate, wherein the electron transport layer is the above-described [1] to [42] ] The organic electroluminescent element containing the compound of any one of clauses.

The compound of the present invention is stable even when a voltage is applied in a thin film state and has a feature of high charge transport capability. The compound of the present invention is suitable as a charge transport material in an organic EL device. By using the compound of this invention for the electron carrying layer of an organic EL element, the organic EL element which has a low drive voltage can be obtained. By using the organic EL element of the present invention, a high-performance display device such as full-color display can be created.

式中、Ｇは単結合ではないｎ価の連結基である。ｎ価の連結基とはｎ価の原子、ｎ価の基およびｎ個の遊離原子価をもつ環系を指す総称であり、かつ、ｎ価の連結基はこれらを組み合わせて構成されてもよい。ｎ価の連結基が非対称な構造である場合も、ｎ個の４，３’−ビピリジル基は該連結基の任意の位置に結合してよい。ｎ価の連結基Ｇについての詳しい説明は後述する。ｎは２〜４の整数である。 Hereinafter, the present invention will be described in more detail.
<Description of compound>
1st invention of this application is a compound which has a 4,3'- bipyridyl group represented by following formula (1).

In the formula, G is an n-valent linking group that is not a single bond. An n-valent linking group is a generic term that refers to a ring system having an n-valent atom, an n-valent group, and n free valences, and the n-valent linking group may be formed by combining them. . Even when the n-valent linking group has an asymmetric structure, n 4,3′-bipyridyl groups may be bonded to any position of the linking group. Detailed description of the n-valent linking group G will be described later. n is an integer of 2-4.

In the present specification, a group formed by R ^{1 to} R ⁸ and a 4,3′-bipyridyl nucleus is referred to as a 4,3′-bipyridyl group. One of R ^{1 to} R ⁴ in the 4,3′-bipyridyl group is a free valence bonded to G, and the others are independently hydrogen or a monovalent group. R ^{5 to} R ⁸ are independently hydrogen or a monovalent group. The n 4,3′-bipyridyl groups may be the same or different, but are preferably the same. The notations “n free valences” in the linking group G and “free valences bound to G” in the 4,3′-bipyridyl group are G and 4,3′-bipyridyl groups are free. It does not represent the presence of a group (radical). “Free valence” refers to a so-called “bond” that is bonded to another group or atom by a covalent bond. That is, the expression “ ^one of R ^{1 to} R ⁴ in the 4,3′-bipyridyl group is a free valence bonded to G” is any of R ^{1 to} R ⁴ in the 4,3′-bipyridyl group. One of them represents a state in which it is bonded to an atom having a free valence of the linking group G.

The monovalent group in R ^{1 to} R ⁸ is a nitro group, a cyano group, a dimesitylboryl group, an aryl having 6 to 12 carbon atoms, or an alkyl having 1 to 12 carbon atoms. The alkyl may be linear, branched or cyclic. Specific examples of the monovalent group are phenyl, 2-biphenylyl, 3-biphenylyl, 4-biphenylyl, 1-naphthyl, 2-naphthyl, methyl, t-butyl, and cyclohexyl. R ^{5 to} R ⁸ are preferably hydrogen.

In the 4,3′-bipyridyl group, R ¹ , R ² or R ³ is preferably bonded to G. R ^{1 to} R ⁴ that do not participate in bonding with G are preferably hydrogen.

In formula (1), n is most preferably 2, then 3 is preferred, and then 4 is preferred. One reason is that the compound is easy to produce. Secondly, it is considered that the molecular weight does not become extremely large and the sublimation property is relatively high, and an advantage that it is easy to form a film at the time of manufacturing an organic EL element can be expected.

Ｒ^９〜Ｒ^１２の１つはＧに結合する遊離原子価であり、それ以外は水素である。ここで、化合物の合成の容易さにおいてはＲ^１０またはＲ^１１がＧに結合することが好ましい。Ｒ^１３〜Ｒ^１６の１つはＧに結合する遊離原子価であり、それ以外は水素である。ここで、化合物の合成の容易さにおいてはＲ^１４またはＲ^１５がＧに結合することが好ましい。２つの４，３’−ビピリジル基は同一でもよく、異なっていてもよいが、同一である方が好ましい。また、ｎ＝２の場合、Ｇはパラテルフェニレンの持つエネルギーギャップより小さくなる事が好ましい。その理由はπ共役系が拡がる事で隣接分子間の電荷移動が容易になると考えられ、駆動電圧の低下に繋がることが期待されるからである。 <Compound with n = 2>
The compound in which n is 2 is specifically represented by the following formula (2).

One of R ^{9 to} R ¹² is a free valence bonded to G, and the other is hydrogen. Here, R ¹⁰ or R ¹¹ is preferably bonded to G for the ease of synthesis of the compound. One of R ^{13 to} R ¹⁶ is a free valence bonded to G, and the other is hydrogen. Here, R ¹⁴ or R ¹⁵ is preferably bonded to G in terms of the ease of synthesis of the compound. The two 4,3′-bipyridyl groups may be the same or different, but are preferably the same. When n = 2, G is preferably smaller than the energy gap of paraterphenylene. The reason is that it is considered that the charge transfer between adjacent molecules is facilitated by the expansion of the π-conjugated system, which is expected to lead to a decrease in driving voltage.

Ｇ^１は独立して、下記の式（Ａ−１）〜（Ａ−２１）および式（Ｂ−１）〜（Ｂ−４０）で表される化合物の群から選択される１つから誘導される２価の基である。以降、式（Ａ−１）〜（Ａ−２１）で表される化合物の群をＡ群、式（Ｂ−１）〜（Ｂ−４０）で表される化合物の群をＢ群と称することがある。 G is one selected from the group of linking groups represented by the following formulas (G1) to (G3). In formulas (G2) and (G3), G ¹ may be the same or different.

G ¹ is independently derived from one selected from the group of compounds represented by the following formulas (A-1) to (A-21) and formulas (B-1) to (B-40). A divalent group. Hereinafter, the group of compounds represented by formulas (A-1) to (A-21) is referred to as Group A, and the group of compounds represented by Formulas (B-1) to (B-40) is referred to as Group B. There is.

In the above formulas (A-1) to (A-21) and (B-1) to (B-40), R is independently hydrogen, alkyl having 1 to 8 carbons, or cyclohexane having 3 to 10 carbons. Alkyl or aryl having 6 to 20 carbon atoms. The alkyl having 1 to 8 carbon atoms may be either a straight chain or branched chain, and examples thereof include a straight chain alkyl having 1 to 8 carbon atoms and a branched chain alkyl having 3 to 8 carbon atoms. Examples of linear alkyl having 1 to 8 carbon atoms are methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl and n-octyl. Examples of branched alkyl having 3 to 8 carbon atoms are isopropyl, isobutyl, s-butyl, t-butyl, isopentyl, neopentyl, t-pentyl, 1-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethyl. Butyl, 2-ethylbutyl, 1-methylhexyl, t-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl and the like. Examples of cycloalkyl having 3 to 10 carbon atoms are cyclopropyl, cyclobutyl, cyclopentyl, methylcyclopentyl, cyclohexyl, methylcyclohexyl, dimethylcyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl and the like. Examples of aryl having 6 to 20 carbon atoms include phenyl, tolyl, xylyl, biphenylyl, naphthyl, anthracenyl, phenanthryl, terphenylyl, fluorenyl, pyrenyl and the like. Preferred R is hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl, and 2-naphthyl.

The divalent group derived from the compounds represented by formulas (A-1) to (A-21) and formulas (B-1) to (B-40) is located at a position other than an atom having a free valence. It may have a substituent. Specific examples of the substituent are phenyl, 2-biphenylyl, 3-biphenylyl, 4-biphenylyl, 1-naphthyl, 2-naphthyl, methyl, t-butyl, cyclohexyl, m-terphenyl-2′-yl and m-terphenyl. -5'-yl.

Ｒ^１７〜Ｒ^２０の１つはＧに連結する遊離原子価であり、それ以外は水素である。ここで、化合物の合成の容易さにおいてはＲ^１８またはＲ^１９がＧに結合することが好ましい。Ｒ^２１〜Ｒ^２４の１つはＧに連結する遊離原子価であり、それ以外は水素である。ここで、化合物の合成の容易さにおいてはＲ^２２またはＲ^２３がＧに結合することが好ましい。Ｒ^２５〜Ｒ^２８の１つはＧに連結する遊離原子価であり、それ以外は水素である。ここで、化合物の合成の容易さにおいてはＲ^２６またはＲ^２７がＧに結合することが好ましい。３つの４，３’−ビピリジル基は同一でもよく、異なっていてもよいが、同一である方が好ましい。 <Compound with n = 3>
The compound in which n is 3 is specifically represented by the following formula (3).

One of R ^{17 to} R ²⁰ is a free valence linked to G, and the other is hydrogen. Here, R ¹⁸ or R ¹⁹ is preferably bonded to G in terms of the ease of synthesis of the compound. One of R ^{21 to} R ²⁴ is a free valence linked to G, and the other is hydrogen. Here, R ²² or R ²³ is preferably bonded to G in terms of the ease of synthesis of the compound. One of R ^{25 to} R ²⁸ is the free valence linked to G, the other is hydrogen. Here, R ²⁶ or R ²⁷ is preferably bonded to G in terms of the ease of synthesis of the compound. The three 4,3′-bipyridyl groups may be the same or different, but are preferably the same.

Ｇ^１は独立して、前記のＡ群およびＢ群の化合物から選択される１つから誘導される２価の基である。 G is a linking group represented by the following formula (G4) or (G5). In Formula (G5), G ¹ may be the same or different, but the same is preferable.

G ¹ is independently a divalent group derived from one selected from the group A and group B compounds.

G ^2A is one selected from the group of trivalent groups represented by the following formulas (E-1) to (E-9), and G ^2B is boron, phosphoryl group, or the formula (E- 1) to one selected from the group of trivalent groups represented by (E-9).

Ｒ^２９〜Ｒ^３２の１つはＧに連結する遊離原子価であり、それ以外は水素である。ここで、化合物の合成の容易さにおいてはＲ^３０またはＲ^３１がＧに結合することが好ましい。Ｒ^３３〜Ｒ^３６の１つはＧに連結する遊離原子価であり、それ以外は水素である。ここで、化合物の合成の容易さにおいてはＲ^３４またはＲ^３５がＧに結合することが好ましい。Ｒ^３７〜Ｒ^４０の１つはＧに連結する遊離原子価であり、それ以外は水素である。ここで、化合物の合成の容易さにおいてはＲ^３８またはＲ^３９がＧに結合することが好ましい。Ｒ^４１〜Ｒ^４４の１つはＧに連結する遊離原子価であり、それ以外は水素である。ここで、化合物の合成の容易さにおいてはＲ^４２またはＲ^４３がＧに結合することが好ましい。４つの４，３’−ビピリジル基は同一でもよく、異なっていてもよいが、同一である方が好ましい。 <Compound with n = 4>
The compound in which n is 4 is specifically represented by the following formula (4).

One of R ^{29 to} R ³² is a free valence linked to G, and the other is hydrogen. Here, R ³⁰ or R ³¹ is preferably bonded to G in terms of the ease of synthesis of the compound. One of R ^{33 to} R ³⁶ is a free valence linked to G, and the other is hydrogen. Here, R ³⁴ or R ³⁵ is preferably bonded to G in terms of the ease of synthesis of the compound. One of R ^{37 to} R ⁴⁰ is a free valence linked to G, and the other is hydrogen. Here, R ³⁸ or R ³⁹ is preferably bonded to G in terms of the ease of synthesis of the compound. One of R ^{41 to} R ⁴⁴ is a free valence linked to G, and the other is hydrogen. Here, R ⁴² or R ⁴³ is preferably bonded to G in terms of the ease of synthesis of the compound. The four 4,3′-bipyridyl groups may be the same or different, but are preferably the same.

Ｇ^１は独立して、前記のＡ群およびＢ群の化合物から選択される１つから誘導される２価の基である。 G is a linking group represented by the following formula (G6) or (G7). In formula (G7), G ¹ may be the same or different, but the same is preferable.

G ¹ is independently a divalent group derived from one selected from the group A and group B compounds.

G ^3A is one selected from the group of tetravalent groups represented by the following formulas (F-1) to (F-8), and G ^3B is carbon, silicon, or the formula (F-1). ) To (F-8) and one selected from the group of tetravalent groups.

式（２−１）〜（２−３）においては、式（２−１）および（２−２）が好ましい。式（２−１）〜（２−３）においては、Ｇは式（Ｇ１）であることが好ましく、次いで式（Ｇ３）であることが好ましく、次いで式（Ｇ２）であることが好ましい。 <More detailed description of the compound where n = 2>
Preferred compounds in which n is 2 are represented by the following formulas (2-1) to (2-3).

In the formulas (2-1) to (2-3), the formulas (2-1) and (2-2) are preferable. In formulas (2-1) to (2-3), G is preferably formula (G1), then preferably formula (G3), and then preferably formula (G2).

Ｒは独立して水素、メチル、エチル、へキシル、シクロヘキシル、フェニル、１−ナフチルまたは２−ナフチルである。式（Ｃ−１）〜（Ｃ−１０）で表される２価の基は、遊離原子価をもつ原子以外の位置に置換基を有していてもよい。置換基の具体例はフェニル、２−ビフェニリル、３−ビフェニリル、４−ビフェニリル、１−ナフチル、２−ナフチル、メチル、ｔ−ブチル、シクロヘキシルである。 In the formula (2-1) to (2-3), when G is the formula (G1), it ^{G 1} is a divalent group derived from one selected from the compounds of the group A Is more preferable, and among the group A, a divalent group derived from one selected from the group of compounds represented by formulas (A-1) to (A-4) is more preferable. More preferably, it is one selected from the group of divalent groups represented by (C-1) to (C-10). Among groups C, one selected from the group of divalent groups represented by the following formulas (C-1) to (C-6) is preferable.

R is independently hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl or 2-naphthyl. The divalent group represented by the formulas (C-1) to (C-10) may have a substituent at a position other than an atom having a free valence. Specific examples of the substituent are phenyl, 2-biphenylyl, 3-biphenylyl, 4-biphenylyl, 1-naphthyl, 2-naphthyl, methyl, t-butyl, and cyclohexyl.

In the formulas (2-1) to (2-2), when G is the formula (G2), G ¹ is the same divalent derivative derived from one selected from the group A and B compounds. Are preferably the same divalent group derived from one selected from the group of compounds represented by formulas (A-1) to (A-4), More preferably, they are the same groups selected from the group of divalent groups represented by the above formulas (C-1) to (C-6).

Ｇ^１Ａは独立して、前記のＡ群の化合物から選択される１つから誘導される２価の基であり、Ｇ^１Ｂは独立して、前記のＢ群の化合物から選択される１つから誘導される２価の基である。 In the formulas (2-1) to (2-2), when G is the formula (G3), it is more specifically a linking group represented by the following formulas (G3-1) to (G3-3). Is preferred.

G ^1A is independently a divalent group derived from one selected from the group A compounds, and G ^1B is independently from one selected from the group B compounds. A divalent group to be derived.

Ｒは水素、メチル、エチル、へキシル、シクロヘキシル、フェニル、１−ナフチルまたは２−ナフチルである。式（Ｄ−１）〜（Ｄ−１０）で表される２価の基は、遊離原子価をもつ原子以外の位置に置換基を有していてもよい。置換基の具体例はフェニル、２−ビフェニリル、３−ビフェニリル、４−ビフェニリル、１−ナフチル、２−ナフチル、メチル、ｔ−ブチル、シクロヘキシルである。 In Formulas (2-1) to (2-2), when G is a linking group represented by Formula (G3-1), G ^1B is represented by Formulas (D-1) to (D-10) below. It is preferably the same group selected from the group of divalent groups represented.

R is hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl or 2-naphthyl. The divalent groups represented by formulas (D-1) to (D-10) may have a substituent at a position other than an atom having a free valence. Specific examples of the substituent are phenyl, 2-biphenylyl, 3-biphenylyl, 4-biphenylyl, 1-naphthyl, 2-naphthyl, methyl, t-butyl, and cyclohexyl.

In Formulas (2-1) to (2-2), when G is a linking group represented by Formula (G3-2), G ^1A is represented by Formulas (C-1) to (C-6). And G ^1B is selected from the group of divalent groups represented by the above formulas (D-1) to (D-10). One is preferred.

In Formulas (2-1) to (2-2), when G is a linking group represented by Formula (G3-3), G ^1A is represented by Formulas (C-1) to (C-6). G ^1B is one selected from the group of divalent groups represented, and G ^1B is the same selected from the group of divalent groups represented by the formulas (D-1) to (D-10). The group is preferably.

Ｇ^１Ｂ１は前記の式（Ｄ−１）〜（Ｄ−５）で表される２価の基の群から選択される１つであり、Ｇ^１Ｂ２は前記の式（Ｄ−１）〜（Ｄ−１０）で表される２価の基の群から選択される同一の基である。 In Formulas (2-1) to (2-2), when G is a linking group represented by Formula (G3-1), G is more specifically a linking group represented by Formula (G3-4). More preferably.

G ^1B1 is one selected from the group of divalent groups represented by the above formulas (D-1) to (D-5), and G ^1B2 is the above formula (D-1) to (D -10) is the same group selected from the group of divalent groups represented by

<Specific examples of compounds>
Specific examples of the compounds of the present invention are shown by the formulas listed below, but the present invention is not limited by the disclosure of these specific structures. In the following specific examples, Me represents methyl and t-Bu represents t-butyl.

<Specific Example of Compound Represented by Formula (2-1)>
Specific examples of the compound represented by the formula (2-1) are represented by the following formulas (2-1-1) to (2-1-67). Of these, preferred compounds are represented by formulas (2-1-1) to (2-1-28). More preferred compounds are the formulas (2-1-1) to (2-1-3), (2-1-8) to (2-1-10), (2-1-15), (2-1- 21) and (2-1-23).

<Specific Example of Compound Represented by Formula (2-2)>
Specific examples of the compound represented by the formula (2-2) are represented by the following formulas (2-2-1) to (2-252). Among these, preferred compounds are represented by formulas (2-2-1) to (2-227). More preferred compounds are the formulas (2-2-1) to (2-2-3), (2-2-8) to (2-2-10), (2-2-15), (2-2) 20) and (2-2-22).

<Specific Example of Compound Represented by Formula (2-3)>
Specific examples of the compound represented by the formula (2-3) are represented by the following formulas (2-3-1) to (2-3-12).

<Specific Example of Compound Represented by Formula (3)>
Specific examples of the compound represented by the formula (3) are represented by the following formulas (3-1) to (3-5).

Specific examples of the compound represented by the formula (4) are represented by the following formulas (4-1) to (4-4).

上記式中、Ｇは２価の基または２個の遊離原子価をもつ環系である。Ｒは短鎖のアルキルであり、通常メチル、エチル、イソプロピルなどが好適に用いられる。Ｘは塩素、臭素、ヨウ素、またはトリフラートである。 <Method of compound synthesis>
The compound of the present invention can be synthesized using a known method such as Suzuki coupling reaction or Negishi coupling reaction. A scheme for synthesizing the compound represented by the formula (2) by Suzuki coupling reaction or Negishi coupling reaction is illustrated below.

In the above formula, G is a divalent group or a ring system having two free valences. R is a short-chain alkyl, and usually methyl, ethyl, isopropyl and the like are preferably used. X is chlorine, bromine, iodine, or triflate.

上記式中、Ｇは２価の基または２個の遊離原子価をもつ環系であり、Ｘは塩素、臭素、ヨウ素、またはトリフラートである。

In the above formula, G is a divalent group or a ring system having two free valences, and X is chlorine, bromine, iodine, or triflate.

In Scheme 1, G in which two sites are boronic acid or boronate ester is reacted in a two-step with 4,3′-bipyridine having a reactive group in the presence of a palladium catalyst and a base, and in two locations. A method of reacting G having a reactive group with boronic acid of 4,3′-bipyridine in two steps in the presence of a palladium catalyst and a base was shown. When the same 4,3′-bipyridyl group is introduced into G, in the above process, 4,3′-bipyridine having a reactive group twice the mole of G may be reacted at one time. Then, it is possible to react boronic acid of 4,3′-bipyridine with 2 moles of G at once.

Scheme 2 includes a method in which G, which is a zinc complex at two positions, is reacted with 4,3′-bipyridine having a reactive group in two stages in the presence of a palladium catalyst, and a G having a reactive group at two positions. Shows a method for reacting a zinc complex of 4,3′-bipyridine in two steps in the presence of a palladium catalyst. When the same 4,3′-bipyridyl group is introduced into G, in the above process, 4,3′-bipyridine having a reactive group twice the mole of G may be reacted at one time. Then, a zinc complex of 4,3′-bipyridine having twice the mole of G may be reacted at once.

G is connected to a plurality of divalent groups, or a ring system having a plurality of two free valences is connected, or a ring having a divalent group and two free valences In the case of a combination of systems, for example, -G ¹ -G ^1- , after coupling the 3,3′-bipyridyl group to each single G ¹ using the above coupling reaction, a known cup The target compound may be synthesized by linking G ¹ together in a ring reaction. Also in this coupling reaction, the Suzuki coupling reaction or the Negishi coupling reaction is preferably used.

In addition, when G ¹ is a heterocycle such as oxadiazole, intramolecular cyclization dehydration reaction from hydrazide obtained by reacting a cyclic acid chloride having a 4,3′-bipyridyl group with hydrazine. It is also possible to use a method of synthesis via

The compound represented by Formula (3) or the compound represented by Formula (4) can also be synthesized by appropriately combining the above synthesis methods. As mentioned above, although the synthesis method of the compound of this invention was illustrated, this invention is not restrict | limited by these illustrated synthesis methods.

Specific examples of the palladium catalyst used in the Suzuki coupling reaction include Pd (PPh ₃ ) ₄ , PdCl ₂ (PPh ₃ ) ₂ , Pd (OAc) ₂ , tris (dibenzylideneacetone) dipalladium (0), tris (di) Benzylideneacetone) dipalladium (0) chloroform complex, bis (dibenzylideneacetone) palladium (0) and the like. In order to accelerate the reaction, a phosphine compound may be added to these palladium compounds in some cases. Specific examples of the phosphine compound include tri (t-butyl) phosphine, tricyclohexylphosphine, 1- (N, N-dimethylaminomethyl) -2- (di-t-butylphosphino) ferrocene, 1- (N, N -Dibutylaminomethyl) -2- (di-t-butylphosphino) ferrocene, 1- (methoxymethyl) -2- (di-t-butylphosphino) ferrocene, 1,1'-bis (di-t-butylphosphino) ) Ferrocene, 2,2′-bis (di-t-butylphosphino) -1,1′-binaphthyl, 2-methoxy-2 ′-(di-t-butylphosphino) -1,1′-binaphthyl, 2- And dicyclohexylphosphino-2 ′, 6′-dimethoxybiphenyl. Specific examples of the base used in this reaction are sodium carbonate, potassium carbonate, cesium carbonate, sodium bicarbonate, sodium hydroxide, potassium hydroxide, barium hydroxide, sodium ethoxide, sodium t-butoxide, sodium acetate, phosphoric acid. Tripotassium, potassium fluoride and the like. Furthermore, specific examples of the solvent used in this reaction are benzene, toluene, xylene, N, N-dimethylformamide, tetrahydrofuran, diethyl ether, t-butylmethyl ether, 1,4-dioxane, methanol, ethanol, Isopropyl alcohol and the like. These solvents can be appropriately selected and may be used alone or as a mixed solvent.

Specific examples of the palladium catalyst used in the Negishi coupling reaction include Pd (PPh ₃ ) ₄ , PdCl ₂ (PPh ₃ ) ₂ , Pd (OAc) ₂ , tris (dibenzylideneacetone) dipalladium (0), tris (di) Benzylideneacetone) dipalladium (0) chloroform complex, bis (dibenzylideneacetone) palladium (0), bis (tri-t-butylphosphino) palladium (0), (1,1′-bis (diphenylphosphino) ferrocene) Such as dichloropalladium (II). Furthermore, specific examples of the solvent used in this reaction are benzene, toluene, xylene, N, N-dimethylformamide, tetrahydrofuran, diethyl ether, t-butylmethyl ether, 1,4-dioxane and the like. These solvents can be appropriately selected and may be used alone or as a mixed solvent.

When the compound of the present invention is used for an electron injection layer or an electron transport layer in an organic EL device, it is stable when an electric field is applied, and light emission can be obtained at a low voltage. These represent that the compound of the present invention is excellent as an electron injecting material or an electron transporting material for an electroluminescent device. The electron injection layer mentioned here is a layer for receiving electrons from the cathode to the organic layer, and the electron transport layer is a layer for transporting the injected electrons to the light emitting layer. The electron transport layer can also serve as the electron injection layer. The material used for each layer is referred to as an electron injection material and an electron transport material.

<Description of organic EL element>
2nd invention of this application is an organic EL element which contains the compound represented by Formula (1) of this invention in an electron injection layer or an electron carrying layer. The organic EL element of the present invention has a low driving voltage and high durability during driving.

Although the structure of the organic EL device of the present invention has various modes, it is basically a multilayer structure in which at least a hole transport layer, a light emitting layer, and an electron transport layer are sandwiched between an anode and a cathode. Examples of the specific configuration of the device are (1) anode / hole transport layer / light emitting layer / electron transport layer / cathode, (2) anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer. / Cathode, (3) anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode, etc.

Since the compound of the present invention has high electron injecting property and electron transporting property, it can be used for an electron injecting layer or an electron transporting layer alone or in combination with other materials. The organic EL device of the present invention emits blue, green, red and white light by combining a hole injection layer, a hole transport layer, a light emitting layer, etc. using other materials with the electron transport material of the present invention. It can also be obtained.

The light-emitting material or light-emitting dopant that can be used in the organic EL device of the present invention is daylight fluorescence as described in the Polymer Society of Japan, Polymer Functional Materials Series “Optical Functional Materials”, Joint Publication (1991), P236. Materials, fluorescent brighteners, laser dyes, organic scintillators, various fluorescent analysis reagents and other luminescent materials, supervised by Koji Koji, “Organic EL materials and displays” published by CMC Publishing Co., Ltd. (2001) P155-156 And a light emitting material of a triplet material as described in P170 to 172.

The compounds that can be used as the light emitting material or the light emitting dopant are polycyclic aromatic compounds, heteroaromatic compounds, organometallic complexes, dyes, polymer light emitting materials, styryl derivatives, aromatic amine derivatives, coumarin derivatives, borane derivatives, oxazines. Derivatives, compounds having a spiro ring, oxadiazole derivatives, fluorene derivatives and the like. Examples of the polycyclic aromatic compound are anthracene derivatives, phenanthrene derivatives, naphthacene derivatives, pyrene derivatives, chrysene derivatives, perylene derivatives, coronene derivatives, rubrene derivatives, and the like. Examples of heteroaromatic compounds include oxadiazole derivatives, pyrazoloquinoline derivatives, pyridine derivatives, pyran derivatives, phenanthroline derivatives, silole derivatives, thiophene derivatives having a triphenylamino group, quinacridone derivatives having a dialkylamino group or a diarylamino group Etc. Examples of organometallic complexes are zinc, aluminum, beryllium, europium, terbium, dysprosium, iridium, platinum, osmium, gold, etc., quinolinol derivatives, benzoxazole derivatives, benzothiazole derivatives, oxadiazole derivatives, thiadiazole derivatives, A complex with a benzimidazole derivative, a pyrrole derivative, a pyridine derivative, a phenanthroline derivative, or the like. Examples of dyes are xanthene derivatives, polymethine derivatives, porphyrin derivatives, coumarin derivatives, dicyanomethylenepyran derivatives, dicyanomethylenethiopyran derivatives, oxobenzanthracene derivatives, carbostyril derivatives, perylene derivatives, benzoxazole derivatives, benzothiazole derivatives, benzimidazoles And pigments such as derivatives. Examples of the polymer light-emitting material include polyparaphenyl vinylene derivatives, polythiophene derivatives, polyvinyl carbazole derivatives, polysilane derivatives, polyfluorene derivatives, polyparaphenylene derivatives, and the like. Examples of styryl derivatives are amine-containing styryl derivatives, styrylarylene derivatives, and the like.

Other electron transport materials used in the organic EL device of the present invention are arbitrarily selected from compounds that can be used as electron transport compounds in photoconductive materials and compounds that can be used in the electron transport layer and electron injection layer of organic EL devices. Can be used.

Specific examples of such electron transport materials include quinolinol metal complexes, 2,2′-bipyridyl derivatives, phenanthroline derivatives, diphenylquinone derivatives, perylene derivatives, oxadiazole derivatives, thiophene derivatives, triazole derivatives, thiadiazole derivatives, oxine derivatives. Metal complexes, quinoxaline derivatives, polymers of quinoxaline derivatives, benzazole compounds, gallium complexes, pyrazole derivatives, perfluorinated phenylene derivatives, triazine derivatives, pyrazine derivatives, benzoquinoline derivatives, imidazopyridine derivatives, borane derivatives, and the like.

Regarding the hole injection material and the hole transport material used in the organic EL device of the present invention, in a photoconductive material, a compound conventionally used as a charge transport material for holes or a hole injection of an organic EL device is used. Any known material used for the layer and the hole transport layer can be selected and used. Specific examples thereof are carbazole derivatives, triarylamine derivatives, phthalocyanine derivatives and the like.

Each layer constituting the organic EL element of the present invention can be formed by forming a material to constitute each layer into a thin film by a method such as a vapor deposition method, a spin coat method, or a cast method. The thickness of each layer formed in this way is not particularly limited and can be appropriately set according to the properties of the material, but is usually in the range of 2 nm to 5000 nm. Note that it is preferable to adopt a vapor deposition method as a method of thinning the light emitting material from the viewpoint that a homogeneous film can be easily obtained and pinholes are hardly generated. When thinning using the vapor deposition method, the vapor deposition conditions differ depending on the type of the light emitting material of the present invention. Deposition conditions generally include a boat heating temperature of 50 to 400 ° C., a vacuum degree of 10 ⁻⁶ to 10 ⁻³ Pa, a deposition rate of 0.01 to 50 nm / second, a substrate temperature of −150 to + 300 ° C., and a film thickness of 5 nm to 5 μm. It is preferable to set appropriately within the range.

The organic EL device of the present invention is preferably supported by a substrate in any of the structures described above. The substrate only needs to have mechanical strength, thermal stability, and transparency, and glass, a transparent plastic film, and the like can be used. As the anode material, metals, alloys, electrically conductive compounds and mixtures thereof having a work function larger than 4 eV can be used. Specific examples thereof include metals such as Au, CuI, indium tin oxide (hereinafter abbreviated as ITO), SnO ₂ , ZnO, and the like.

Cathode materials can use metals, alloys, electrically conductive compounds, and mixtures thereof with work functions of less than 4 eV. Specific examples thereof are aluminum, calcium, magnesium, lithium, magnesium alloy, aluminum alloy and the like. Specific examples of the alloy include aluminum / lithium fluoride, aluminum / lithium, magnesium / silver, and magnesium / indium. In order to efficiently extract light emitted from the organic EL element, it is desirable that at least one of the electrodes has a light transmittance of 10% or more. The sheet resistance as the electrode is preferably several hundred Ω / □ or less. Although the film thickness depends on the properties of the electrode material, it is usually set in the range of 10 nm to 1 μm, preferably 10 to 400 nm. Such an electrode can be produced by forming a thin film by a method such as vapor deposition or sputtering using the electrode material described above.

Next, as an example of a method for producing an organic EL device using the light emitting material of the present invention, an organic material comprising the above-mentioned anode / hole injection layer / hole transport layer / light emitting layer / electron transport material of the present invention / cathode is used. A method for creating an EL element will be described. A thin film of an anode material is formed on a suitable substrate by vapor deposition to produce an anode, and then a thin film of a hole injection layer and a hole transport layer is formed on the anode. A light emitting layer thin film is formed thereon. On this light emitting layer, the electron transport material of this invention is vacuum-deposited, a thin film is formed, and it is set as an electron carrying layer. Furthermore, the target organic EL element is obtained by forming the thin film which consists of a substance for cathodes by a vapor deposition method, and making it a cathode. In the production of the organic EL element described above, the production order can be reversed, and the cathode, the electron transport layer, the light emitting layer, the hole transport layer, the hole injection layer, and the anode can be produced in this order.

When a DC voltage is applied to the organic EL device thus obtained, the anode may be applied with a positive polarity and the cathode with a negative polarity. When a voltage of about 2 to 40 V is applied, a transparent or translucent electrode is applied. Luminescence can be observed from the side (anode or cathode, and both). The organic EL element also emits light when an alternating voltage is applied. The alternating current waveform to be applied may be arbitrary.
Hereinafter, the present invention will be described in more detail based on examples.

Synthesis Example 1: Synthesis of Compound of Formula (2-1-2) <Synthesis of 6-chloro-4,3′-bipyridine>
3-Pyridineboronic acid, 2-chloro-4-bromopyridine, Pd (PPh ₃ ) ₄ , sodium carbonate, toluene, ethanol and pure water were placed in a flask and stirred overnight at reflux temperature in an argon atmosphere. After completion of the heating, the reaction solution was cooled to room temperature and the organic layer was extracted. The organic layer was concentrated, the concentrate was purified by silica gel column chromatography, and then recrystallized from heptane to obtain 6-chloro-4,3′-bipyridine.

<Synthesis of 2-phenylanthracene>
A flask is charged with 5.00 g of 2-chloroanthracene, 4.3 g of phenylboronic acid, 538 mg of tris (dibenzylideneacetone) dipalladium (0), 494 mg of tricyclohexylphosphine, 9.98 g of tripotassium phosphate, and 75 ml of toluene. The mixture was stirred at the reflux temperature for 2 hours under the atmosphere. After completion of heating, 1.5 liters of toluene was added to the reaction solution, cooled to room temperature and filtered, and the filtrate was purified by silica gel column chromatography (mobile phase: heptane). The solvent was distilled off under reduced pressure, and the concentrate was recrystallized from toluene to obtain 5.0 g of 2-phenylanthracene.

<Synthesis of 9,10-dibromo-2-phenylanthracene>
In a flask under a nitrogen atmosphere, 3.32 g of 2-phenylanthracene was dissolved in 400 ml of dichloromethane. A solution prepared by dissolving 5.00 g of bromine in 30 ml of carbon tetrachloride was added dropwise over 15 minutes. After completion of the dropping, the mixture was stirred for 2 hours at room temperature, and the reaction was stopped with an aqueous sodium thiosulfate solution. The organic layer was extracted, the solvent was distilled off under reduced pressure, and the resulting concentrate was recrystallized from 50 ml of toluene to obtain 4.4 g of 9,10-dibromo-2-phenylanthracene.

<Synthesis of 9,10-bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolanyl) -2-phenylanthracene>
9,10-dibromo-2-phenylanthracene 10.0 g, bis (pinacolato) diboron 14.8 g, bis (dibenzylideneacetone) palladium (0) 838 mg, tricyclohexylphosphine 1.02 g, potassium acetate 7.15 g and 1, 4-Dioxane (50 ml) was placed in a flask and stirred at reflux temperature for 8 hours under an argon atmosphere. After the heating was completed, toluene was added to the reaction solution, and after cooling to room temperature, the solid was filtered off and the filtrate was concentrated. The concentrate was purified by silica gel column chromatography (mobile phase: toluene) and then recrystallized from a tetrahydrofuran / heptane mixed solution to give 9,10-bis (4,4,5,5-tetramethyl-1,3,2). -Dioxaborolanyl) -2-phenylanthracene 8.3 g was obtained.

<Synthesis of 9,10-bis (4,3′-bipyridin-6-yl) -2-phenylanthracene>
9,10-bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolanyl) -2-phenylanthracene 2.02 g, 6-chloro-4,3′-bipyridine 9 g, 915 mg of tris (dibenzylideneacetone) dipalladium (0), 840 mg of tricyclohexylphosphine, 8.48 g of tripotassium phosphate, and 50 ml of toluene were placed in a flask and stirred at reflux temperature for 7 hours under an argon atmosphere. After completion of heating, the reaction solution was cooled to room temperature and washed with pure water. The organic layer was concentrated, and the concentrate was purified by activated alumina column chromatography (mobile phase: toluene / ethyl acetate). The solvent was distilled off under reduced pressure, and the concentrate was washed with ethyl acetate and recrystallized from toluene to obtain 360 mg of 9,10-bis (4,3′-bipyridin-6-yl) -2-phenylanthracene.
1H-NMR (CDCl ₃ ): 7.3-7.5 (m, 6H), 7.5-7.6 (m, 2H), 7.7-7.9 (m, 10H), 8.0-8.1 (m, 2H), 8.7 (m, 2H) , 9.0-9.1 (m, 4H).

By appropriately selecting a raw material compound, another light emitting material of the present invention can be synthesized by a method according to the above synthesis example.

A 25 mm × 75 mm × 1.1 mm glass substrate (manufactured by Tokyo Sanyo Vacuum Co., Ltd.) on which ITO was deposited to a thickness of 150 nm was used as a transparent support substrate. This transparent support substrate is fixed to a substrate holder of a commercially available vapor deposition apparatus (manufactured by Vacuum Kiko Co., Ltd.), and a molybdenum vapor deposition boat containing copper phthalocyanine, N, N′-diphenyl-N, N′-dinaphthyl-4 , 4′-diaminobiphenyl (hereinafter abbreviated as NPD), molybdenum vapor deposition boat, the following compound (A): 9-phenyl-10- [6- (1,1 ′; 3,1 ″ ) Terphenyl-5'-yl] naphthalen-2-yl] anthracene-containing molybdenum vapor deposition boat, styrylamine derivative (B) below: N, N, N ', N'-tetra (4-biphenylyl)- Molybdenum vapor deposition boat containing 4,4′-diaminostilbene, molybdenum vapor deposition boat containing compound (2-1-2), molybdenum vapor deposition boat containing lithium fluoride, and aluminum A tungsten vapor deposition boat with a refrigeration was installed.

Depressurize the vacuum chamber to 1 × 10 ⁻³ Pa, heat the vapor deposition boat containing copper phthalocyanine, and form a hole injection layer by vapor deposition to a film thickness of 20 nm, and then vapor deposition with NPD The boat was heated and NPD was deposited to a film thickness of 30 nm to form a hole transport layer. Next, the vapor deposition boat containing the compound (A) and the vapor deposition boat containing the compound (B) were heated at the same time and vapor-deposited to a film thickness of 30 nm to form a light emitting layer. The deposition rate was adjusted so that the weight ratio of compound (A) to compound (B) was approximately 95 to 5. Next, the evaporation boat containing the compound (2-2-1) was heated and evaporated to a film thickness of 20 nm to form an electron transport layer. The above deposition rate was 0.001 to 3.0 nm / second. Thereafter, the vapor deposition boat containing lithium fluoride is heated to deposit at a deposition rate of 0.003 to 0.01 nm / second so that the film thickness is 0.5 nm, and then the vapor deposition boat containing aluminum is heated. Then, an organic EL device was obtained by vapor deposition at a vapor deposition rate of 0.1 to 1.0 nm / second so as to have a film thickness of 100 nm. When a direct current voltage was applied using the ITO electrode as the anode and the lithium fluoride / aluminum electrode as the cathode, blue light emission with a wavelength of about 455 nm was obtained. In addition, a constant current driving test was performed at a current density for obtaining an initial luminance of 1000 cd / m ² . The drive test starting voltage was 6.41 V, and the luminance after 80 hours was 730 cd / m ² .

(Comparative Example 1)
An organic EL device was obtained in the same manner as in Example 2 except that the compound (2-1-2) was changed to the compound (C) (Compound II-4 described in Patent Document 2). A constant current driving test was performed using an ITO electrode as an anode and a lithium fluoride / aluminum electrode as a cathode at a current density for obtaining an initial luminance of 1000 cd / m ² . The drive test starting voltage was 3.71 V, and the luminance after 80 hours was 496 cd / m ² .

(Comparative Example 2)
An organic EL device was obtained in the same manner as in Example 2 except that the compound (2-1-2) was changed to tris (8-quinolinol) aluminum (Alq ₃ ). A constant current driving test was performed using an ITO electrode as an anode and a lithium fluoride / aluminum electrode as a cathode at a current density for obtaining an initial luminance of 1000 cd / m ² . The drive test start voltage was 6.77 V, and the luminance after 80 hours was 788 cd / m ² .

According to a preferred aspect of the present invention, it is possible to provide an organic EL element with better performance at a driving voltage, and to provide a high-performance display device including the organic EL element.

Claims (44)

A compound represented by the following formula (1).

Wherein G is an n-valent linking group and n is an integer of 2 to 4;
R ^{1 to} R ⁴ are independently hydrogen, a monovalent group or a free valence bonded to G, and R ^{5 to} R ⁸ are independently hydrogen or a monovalent group, but R ^{1 to} R ⁴ Is the free valence attached to G; and the n 4,3′-bipyridyl groups may be the same or different. The compound according to claim 1, wherein one of R ^{1 to} R ⁴ is a free valence bonded to G, the other is hydrogen, and R ^{5 to} R ⁸ are hydrogen. The compound of Claim 2 represented by following formula (2).

In the formula, G is one selected from the group of groups represented by the following formulas (G1) to (G3); one of R ^{9 to} R ¹² is a free valence bonded to G; The other is hydrogen; and one of R ¹³ -R ¹⁶ is the free valence bonded to G, the other is hydrogen.

In the formula, G ¹ is independently one selected from the group of compounds represented by the following formulas (A-1) to (A-21) and formulas (B-1) to (B-40) Is a divalent group derived from

In the above formula, R is independently hydrogen, alkyl having 1 to 8 carbons, cycloalkyl having 3 to 10 carbons, or aryl having 6 to 20 carbons; formulas (A-1) to (A- 21) and the divalent group derived from the compounds represented by formulas (B-1) to (B-40) may have a substituent at a position other than the atom having a free valence. The compound of Claim 3 represented by a following formula (2-1).

In the formula, the definition of G is the same as G in the formula (2) according to claim 3. G is a linking group represented by the formula (G1) according to claim 3, selected from the group of compounds formula (G1) Medium ^{G 1} is represented by the formula (A-1) ~ (A -21) 5. The compound of claim 4, which is a divalent group derived from one of the G is a linking group represented by the formula (G1) according to claim 3, selected from the group of compounds formula (G1) Medium ^{G 1} is represented by the formula (A-1) ~ (A -4) 5. The compound of claim 4, which is a divalent group derived from one of the G is a linking group represented by the formula (G1) according to claim 3, wherein (G1) Medium ^{G 1} is the following formula (C-1) ~ expressed divalent be in (C-10) 5. A compound according to claim 4 which is one selected from the group of groups.

In the formula, R is independently hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl or 2-naphthyl; a divalent group represented by formulas (C-1) to (C-10) The group may have a substituent at a position other than the atom having a free valence. G is a linking group represented by the formula (G2) as claimed in claim 3, wherein (G2) Medium ^{G 1} is the formula (A-1) ~ (A -21) and formula (B-1) ~ ( The compound according to claim 4, which is the same divalent group derived from one selected from the group of compounds represented by B-40). G is a linking group represented by the formula (G2) as claimed in claim 3, wherein (G2) Medium ^{G 1} is the following formula (C-1) ~ 2 divalent represented by (C-6) 5. A compound according to claim 4 which is the same group selected from the group of groups.

In the formula, R is hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl or 2-naphthyl; the divalent group represented by the formulas (C-1) to (C-6) is: You may have a substituent in positions other than the atom which has free valence. The compound according to claim 4, wherein G is one selected from the group of groups represented by the following formulas (G3-1) to (G3-3).

In the formula, G ^1A is independently a divalent group derived from one selected from the group of compounds represented by formulas (A-1) to (A-21) according to claim 3. Yes; G ^1B is independently a divalent group derived from one selected from the group of compounds represented by formulas (B-1) to (B-40) according to claim 3. . G is a linking group represented by the formula (G3-2); G ^1A is the same selected from the group of divalent groups represented by the following formulas (C-1) to (C-6) The compound according to claim 10, which is a group, and G ^1B is one selected from the group of divalent groups represented by the following formulas (D-1) to (D-10).

Wherein R is independently hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl or 2-naphthyl; formulas (C-1) to (C-6) and formula (D-1) The divalent group represented by (D-10) may have a substituent at a position other than the atom having a free valence. G is a linking group represented by the formula (G3-3); G ^1A is one selected from the group of divalent groups represented by the following formulas (C-1) to (C-6) The compound according to claim 10, wherein G ^1B is the same group selected from the group of divalent groups represented by the following formulas (D-1) to (D-10).

Wherein R is independently hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl or 2-naphthyl; formulas (C-1) to (C-6) and formula (D-1) The divalent group represented by (D-10) may have a substituent at a position other than an atom having a free valence. The compound of Claim 10 whose G is a coupling group represented by a following formula (G3-4).

In the formula, G ^1B1 is one selected from the group of divalent groups represented by the following formulas (D-1) to (D-5), and G ^1B2 is the following formula (D-1). It is the same group selected from the group of the bivalent group represented by-(D-10).

In the formula, R is independently hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl or 2-naphthyl; a divalent group represented by formulas (D-1) to (D-10) The group may have a substituent at a position other than the atom having a free valence. The compound of Claim 3 represented by a following formula (2-2).

In the formula, the definition of G is the same as G in the formula (2) according to claim 3. G is a linking group represented by the formula (G1) according to claim 3, selected from the group of compounds formula (G1) Medium ^{G 1} is represented by the formula (A-1) ~ (A -21) 15. A compound according to claim 14 which is a divalent group derived from one of G is a linking group represented by the formula (G1) according to claim 3, selected from the group of compounds formula (G1) Medium ^{G 1} is represented by the formula (A-1) ~ (A -4) 15. A compound according to claim 14 which is a divalent group derived from one of G is a linking group represented by the formula (G1) according to claim 3, wherein (G1) Medium ^{G 1} is the following formula (C-1) ~ expressed divalent be in (C-10) 15. A compound according to claim 14, which is one selected from the group of groups.

In the formula, R is independently hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl or 2-naphthyl; a divalent group represented by formulas (C-1) to (C-10) The group may have a substituent at a position other than the atom having a free valence. G is a linking group represented by the formula (G2) as claimed in claim 3, wherein (G2) Medium ^{G 1} is the formula (A-1) ~ (A -21) and formula (B-1) ~ ( The compound according to claim 14, which is the same divalent group derived from one selected from the group of compounds represented by B-40). G is a linking group represented by the formula (G2) as claimed in claim 3, wherein (G2) Medium ^{G 1} is the following formula (C-1) ~ 2 divalent represented by (C-6) 15. A compound according to claim 14 which is the same group selected from the group of groups.

In the formula, R is hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl or 2-naphthyl; the divalent group represented by the formulas (C-1) to (C-6) is: You may have a substituent in positions other than the atom which has free valence. The compound according to claim 14, wherein G is one selected from the group of groups represented by the following formulas (G3-1) to (G3-3).

In the formula, G ^1A is independently a divalent group derived from one selected from the group of compounds represented by formulas (A-1) to (A-21) according to claim 3. Yes; G ^1B is independently a divalent group derived from one selected from the group of compounds represented by formulas (B-1) to (B-40) according to claim 3. . G is a linking group represented by the formula (G3-2); G ^1A is the same selected from the group of divalent groups represented by the following formulas (C-1) to (C-6) ^21. The compound according to claim 20, which is a group and G ^1B is one selected from the group of divalent groups represented by the following formulas (D-1) to (D-10).

Wherein R is independently hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl or 2-naphthyl; formulas (C-1) to (C-6) and formula (D-1) The divalent group represented by (D-10) may have a substituent at a position other than an atom having a free valence. G is a linking group represented by the formula (G3-3); G ^1A is one selected from the group of divalent groups represented by the following formulas (C-1) to (C-6) The compound according to claim 20, wherein G ^1B is the same group selected from the group of divalent groups represented by the following formulas (D-1) to (D-10).

Wherein R is independently hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl or 2-naphthyl; formulas (C-1) to (C-6) and formula (D-1) The divalent group represented by (D-10) may have a substituent at a position other than an atom having a free valence. The compound of Claim 20 whose G is a coupling group represented by a following formula (G3-4).

In the formula, G ^1B1 is one selected from the group of divalent groups represented by the following formulas (D-1) to (D-5), and G ^1B2 is the following formula (D-1). It is the same group selected from the group of the bivalent group represented by-(D-10).

In the formula, R is independently hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl or 2-naphthyl; a divalent group represented by formulas (D-1) to (D-10) The group may have a substituent at a position other than the atom having a free valence. The compound of Claim 3 represented by a following formula (2-3).

In the formula, the definition of G is the same as G in the formula (2) according to claim 3. G is a linking group represented by the formula (G1) according to claim 3, selected from the group of compounds formula (G1) Medium ^{G 1} is represented by the formula (A-1) ~ (A -21) 25. The compound of claim 24, which is a divalent group derived from one of the G is a linking group represented by the formula (G1) according to claim 3, wherein (G1) Medium ^{G 1} is the following formula (C-1) ~ expressed divalent be in (C-10) 25. A compound according to claim 24 which is one selected from the group of groups.

In the formula, R is independently hydrogen, methyl, ethyl, hexyl, cyclohexyl, phenyl, 1-naphthyl or 2-naphthyl; a divalent group represented by formulas (C-1) to (C-10) The group may have a substituent at a position other than the atom having a free valence. The compound of Claim 2 represented by following formula (3).

In the formula, G is a group represented by the following formula (G4) or (G5); one of R ^{17 to} R ²⁰ is a free valence bonded to G, and the other is hydrogen; ^{One of 21 to} R ²⁴ is a free valence bonded to G and the other is hydrogen; one of R ^{25 to} R ²⁸ is a free valence bonded to G and the other is hydrogen .

In the formula, G ¹ is independently one selected from the group of compounds represented by the following formulas (A-1) to (A-21) and formulas (B-1) to (B-40) G ^2A is one selected from the group of trivalent groups represented by the following formulas (E-1) to (E-9), and G ^2B Is one selected from the group of boron, phosphoryl groups, or trivalent groups represented by formulas (E-1) to (E-9).

In the above formula, R is independently hydrogen, alkyl having 1 to 8 carbons, cycloalkyl having 3 to 10 carbons, or aryl having 6 to 20 carbons; formulas (A-1) to (A- 21) and the divalent group derived from the compounds represented by formulas (B-1) to (B-40) may have a substituent at a position other than the atom having a free valence.

28. The compound according to claim 27, wherein G is a linking group represented by formula (G5), and G ¹ is the same in formula (G5). The compound of Claim 2 represented by following formula (4).

In the formula, G is a group represented by the following formula (G6) or (G7); one of R ^{29 to} R ³² is a free valence bonded to G, and the other is hydrogen; ^{One of 33 to} R ³⁶ is a free valence bonded to G and the other is hydrogen; one of R ^{37 to} R ⁴⁰ is a free valence bonded to G and the other is hydrogen One of R ^{41 to} R ⁴⁴ is a free valence bonded to G, and the other is hydrogen.

In the formula, G ¹ is independently derived from one selected from the group of compounds represented by formulas (A-1) to (A-21) and formulas (B-1) to (B-40). G ^3A is one selected from the group of tetravalent groups represented by the following formulas (F-1) to (F-8); G ^3B is carbon , Silicon, or one selected from the group of tetravalent groups represented by formulas (F-1) to (F-8).

In the above formula, R is independently hydrogen, alkyl having 1 to 8 carbons, cycloalkyl having 3 to 10 carbons, or aryl having 6 to 20 carbons; formulas (A-1) to (A- 21) and the divalent group derived from the compounds represented by formulas (B-1) to (B-40) may have a substituent at a position other than the atom having a free valence.

G is a linking group represented by the formula (G7), ^{G 1} is the same in the formula (G7), the compound according to claim 29. The compound according to claim 3, wherein G is represented by the following formula (5).

In the above formula, R ⁴⁵ is hydrogen, methyl, t-butyl, cyclohexyl, phenyl, naphthyl, biphenylyl or terphenylyl. The compound according to claim 4, wherein G is represented by the following formula (5).

In the above formula, R ⁴⁵ is hydrogen, methyl, t-butyl, cyclohexyl, phenyl, naphthyl, biphenylyl or terphenylyl. The compound according to claim 14, wherein G is represented by the following formula (5).

In the above formula, R ⁴⁵ is hydrogen, methyl, t-butyl, cyclohexyl, phenyl, naphthyl, biphenylyl or terphenylyl. The compound according to claim 3, wherein G is represented by the following formula (6).

In the above formula, R ^{46 to} R ⁴⁹ are independently hydrogen, methyl, t-butyl, cyclohexyl, phenyl, naphthyl, biphenylyl or terphenylyl. The compound according to claim 4, wherein G is represented by the following formula (6).

In the above formula, R ^{46 to} R ⁴⁹ are independently hydrogen, methyl, t-butyl, cyclohexyl, phenyl, naphthyl, biphenylyl or terphenylyl. The compound according to claim 14, wherein G is represented by the following formula (6).

In the above formula, R ^{46 to} R ⁴⁹ are independently hydrogen, methyl, t-butyl, cyclohexyl, phenyl, naphthyl, biphenylyl or terphenylyl. The compound according to claim 3, wherein G is represented by the following formula (7).

In the above formula, R ⁵⁰ and R ⁵¹ are independently hydrogen, methyl, t-butyl, cyclohexyl, phenyl, naphthyl, biphenylyl or terphenylyl. The compound according to claim 4, wherein G is represented by the following formula (7).

In the above formula, R ⁵⁰ and R ⁵¹ are independently hydrogen, methyl, t-butyl, cyclohexyl, phenyl, naphthyl, biphenylyl or terphenylyl. The compound according to claim 14, wherein G is represented by the following formula (7).

In the above formula, R ⁵⁰ and R ⁵¹ are independently hydrogen, methyl, t-butyl, cyclohexyl, phenyl, naphthyl, biphenylyl or terphenylyl. The compound according to claim 3, wherein G is represented by the following formula (8).

The compound of Claim 4 whose G is represented by Formula (8).

The compound according to claim 14, wherein G is represented by formula (8).

The organic electroluminescent element containing the compound of any one of Claims 1-42. 43. An organic electroluminescent device having at least a hole transport layer, a light emitting layer, and an electron transport layer sandwiched between an anode and a cathode on a substrate, wherein the electron transport layer is any one of claims 1-42. An organic electroluminescent device comprising the compound described in 1.