JPWO2013011956A1 - Organic electroluminescence device and compound used therefor - Google Patents

Abstract

An organic electroluminescence device using a monospirobifluorene compound represented by the following general formula in a light emitting layer has high luminous efficiency [at least one of R ^{1 to} R ⁸ is an electron donating group, and the other represents a hydrogen atom, At least one of R ^{9 to} R ¹⁶ is an electron withdrawing group other than a triazino group, and the other represents a hydrogen atom. 11-14 pieces of R ¹ to R ¹⁶ represents a hydrogen atom. ].

Description

  The present invention relates to an organic electroluminescence element (organic EL element) having high luminous efficiency and a luminescent material used therefor.

  Many studies have been conducted to increase the luminous efficiency of organic electroluminescence elements. In particular, various efforts have been made to increase the light emission efficiency by newly developing and combining electron transport materials, hole transport materials, light emitting materials, and the like constituting the organic electroluminescence element. Among them, studies on organic electroluminescence devices using compounds having a spirobifluorene skeleton have been found, and some proposals have been made so far.

  For example, Patent Document 1 describes a phosphorescent organic electroluminescence device using a compound having a spirobifluorene skeleton for a hole blocking layer. Patent Document 2 describes an organic electroluminescence device using a compound having a spirobifluorene skeleton having two carbazole groups bonded as a host material of a light emitting layer. Furthermore, Patent Document 3 describes an organic electroluminescence device using a phenyl vinyl group or a compound having a spirobifluorene skeleton substituted with a phenyl group as a host material of a light emitting layer. Patent Document 4 describes an organic electroluminescence device having a light-emitting layer composed only of a compound having a spirobifluorene skeleton substituted with a biphenyl group. Patent Document 5 describes an organic electroluminescence device having a light emitting layer composed only of benzene or naphthalene compounds substituted with 1 to 3 spirobifluorene rings. Patent Document 6 describes an organic electroluminescence device having a light emitting layer composed of only a benzene compound substituted with 3 to 6 spirobifluorene rings.

JP 2006-528836 A JP 2010-27681 A JP 2001-307879 A JP-A-7-278537 JP 2002-121547 A JP 2006-256882 A

  As described above, various studies have been made on compounds having a spirobifluorene skeleton, and several proposals have been made regarding application to organic electroluminescence devices. However, it cannot be said that exhaustive research has been conducted on all compounds having a spirobifluorene skeleton. In particular, regarding the use of a compound having a spirobifluorene skeleton as a light-emitting material of an organic electroluminescence device, only a part of the compounds have been confirmed to be useful. In addition, no clear relationship has been found between the chemical structure of a compound having a spirobifluorene skeleton and the usefulness of the compound as a light-emitting material. It is difficult to predict. Furthermore, since a compound having a spirobifluorene skeleton is not always easy to synthesize, it may be difficult to provide the compound itself. In consideration of these problems, the present inventors synthesized a compound having a spirobifluorene skeleton that has not been developed and studied so far, and evaluated the usefulness of the organic electroluminescence device as a light emitting material. We proceeded with the study for the purpose of doing this. In addition, a general formula of a compound useful as a light-emitting material has been derived, and extensive studies have been carried out for the purpose of generalizing the structure of an organic electroluminescence device having high luminous efficiency.

  As a result of diligent studies to achieve the above object, the present inventors have found that a specific compound having a spirobifluorene skeleton has excellent properties as a light emitting material of an organic electroluminescence device. Based on this finding, the present inventors have provided the following present invention as means for solving the above-mentioned problems.

［一般式（１）において、Ｒ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５、Ｒ^６、Ｒ^７およびＲ^８は、各々独立に水素原子または電子供与基であって、少なくとも１つは電子供与基を表す。Ｒ^９、Ｒ^１０、Ｒ^１１、Ｒ^１２、Ｒ^１３、Ｒ^１４、Ｒ^１５およびＲ^１６は、各々独立に水素原子またはトリアジノ基以外の電子吸引基であって、少なくとも１つはトリアジノ基以外の電子吸引基を表す。ただし、Ｒ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５、Ｒ^６、Ｒ^７、Ｒ^８、Ｒ^９、Ｒ^１０、Ｒ^１１、Ｒ^１２、Ｒ^１３、Ｒ^１４、Ｒ^１５およびＲ^１６のうちの１１〜１４個は水素原子である。］
［２］ 一般式（１）のＲ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５、Ｒ^６、Ｒ^７およびＲ^８の少なくとも１つが、電子供与基で置換されたアリール基であることを特徴とする［１］に記載の有機エレクトロルミネッセンス素子。
［３］ 一般式（１）のＲ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５、Ｒ^６、Ｒ^７およびＲ^８の少なくとも１つが、下記一般式（２）で表される構造を有することを特徴とする［１］に記載の有機エレクトロルミネッセンス素子。

［一般式（２）において、Ｒ^２１、Ｒ^２２、Ｒ^２３、Ｒ^２４およびＲ^２５は、各々独立に水素原子または電子供与基であって、少なくとも１つは電子供与基を表す。］
［４］ 一般式（１）のＲ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５、Ｒ^６、Ｒ^７およびＲ^８の少なくとも１つが、下記一般式（３）〜（５）のいずれかで表される構造を有することを特徴とする［１］に記載の有機エレクトロルミネッセンス素子。

［上式において、Ｒ^３１およびＲ^３２は、各々独立に置換もしくは無置換のアリール基を表し、Ｒ^３１が表すアリール基とＲ^３２が表すアリール基は連結していてもよい。Ｒ^４１、Ｒ^４２およびＲ^４３は、各々独立に水素原子、置換もしくは無置換のアルキル基、または置換もしくは無置換のアリール基を表し、Ｒ^４１およびＲ^４２は一緒になって環構造を形成していてもよく、Ｒ^４２およびＲ^４３は一緒になって環構造を形成していてもよい。Ｒ^５１、Ｒ^５２およびＲ^５３は、各々独立に水素原子、置換もしくは無置換のアルキル基、または置換もしくは無置換のアリール基を表し、Ｒ^５１およびＲ^５２は一緒になって環構造を形成していてもよく、Ｒ^５２およびＲ^５３は一緒になって環構造を形成していてもよい。］
［５］ 一般式（１）のＲ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５、Ｒ^６、Ｒ^７およびＲ^８の少なくとも１つが、下記一般式（Ａ）〜（Ｃ）のいずれかで表される構造を有することを特徴とする［１］に記載の有機エレクトロルミネッセンス素子。

［一般式（Ａ）において、Ｚ^１は窒素原子、酸素原子、硫黄原子または珪素原子を表し、Ａ^１およびＡ^２として各々独立に芳香環、ヘテロ芳香環、脂肪環または非芳香族ヘテロ環を形成していてもよい。一般式（Ｂ）において、Ｒ^２０は水素原子、アリール基またはＡ^４で表される環構造を形成するのに必要な原子群を表し、Ａ^３およびＡ^４として各々独立に、ヘテロ芳香環または非芳香族ヘテロ環を形成していてもよい。一般式（Ｃ）において、Ｚ^１、Ｚ^２、Ｚ^３およびＺ^４は各々独立に酸素原子または硫黄原子を表す。］
［６］ 一般式（１）のＲ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５、Ｒ^６、Ｒ^７およびＲ^８の少なくとも１つが、下記Ｄ１〜Ｄ１３のいずれかの構造を有することを特徴とする［１］に記載の有機エレクトロルミネッセンス素子。

［７］ 一般式（１）のＲ^９、Ｒ^１０、Ｒ^１１、Ｒ^１２、Ｒ^１３、Ｒ^１４、Ｒ^１５およびＲ^１６の少なくとも１つが、下記一般式（６）〜（９）のいずれかで表される構造を有することを特徴とする［１］〜［６］のいずれか一項に記載の有機エレクトロルミネッセンス素子。

［上式において、Ｒ^６１およびＲ^６２は、各々独立に置換もしくは無置換のアリール基を表す。Ｒ^７１およびＲ^７２は、各々独立に水素原子、置換もしくは無置換のアルキル基、または置換もしくは無置換のアリール基を表し、Ｒ^７１およびＲ^７２は一緒になって環構造を形成していてもよい。Ｒ^８１、Ｒ^８２およびＲ^８３は、各々独立に水素原子、置換もしくは無置換のアルキル基、または置換もしくは無置換のアリール基を表し、Ｒ^８１およびＲ^８２は一緒になって環構造を形成していてもよく、Ｒ^８２およびＲ^８３は一緒になって環構造を形成していてもよい。Ｒ^９１は水素原子、置換もしくは無置換のアルキル基、または置換もしくは無置換のアリール基を表し、Ｚはトリアジン環以外のヘテロ芳香環を形成するのに必要な連結基を表す。］
［８］ 一般式（１）のＲ^９、Ｒ^１０、Ｒ^１１、Ｒ^１２、Ｒ^１３、Ｒ^１４、Ｒ^１５およびＲ^１６の少なくとも１つが、下記のいずれかの構造を有することを特徴とする［１］〜［６］のいずれか一項に記載の有機エレクトロルミネッセンス素子。

［９］ 前記一般式（１）で表される化合物のみからなる発光層を有することを特徴とする［１］〜［８］のいずれか一項に記載の有機エレクトロルミネッセンス素子。
［１０］ 前記一般式（１）で表される化合物を発光層のドーパントとして用いたことを特徴とする［１］〜［８］のいずれか一項に記載の有機エレクトロルミネッセンス素子。
［１１］ 有機層として発光層のみを有することを特徴とする［１］〜［１０］のいずれか一項に記載の有機エレクトロルミネッセンス素子。[1] An organic electroluminescence device having an anode, a cathode, and at least one organic layer including a light emitting layer between the anode and the cathode, and represented by the following general formula (1) in the light emitting layer An organic electroluminescence device comprising a monospirobifluorene compound.

[In General Formula (1), R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are each independently a hydrogen atom or an electron-donating group, and at least one of Represents an electron donating group. R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ are each independently an electron withdrawing group other than a hydrogen atom or a triazino group, at least one of which is other than a triazino group Represents an electron withdrawing group. ^However, the ^{R 1, R 2, R 3} , R 4, R 5, R 6, R 7, R 8, R 9, R 10, R 11, R 12, R 13, R 14, R 15 and ^{R 16} 11-14 of them are hydrogen atoms. ]
[2] At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) is an aryl group substituted with an electron donating group The organic electroluminescence device according to [1], which is characterized in that
[3] At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) has a structure represented by the following general formula (2). The organic electroluminescent element according to [1], which is characterized in that

[In General Formula (2), R ²¹ , R ²² , R ²³ , R ²⁴ and R ²⁵ are each independently a hydrogen atom or an electron-donating group, and at least one represents an electron-donating group. ]
[4] At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) is any one of the following general formulas (3) to (5). The organic electroluminescence device according to [1], which has a structure represented by:

[In the above formula, R ³¹ and R ³² each independently represent a substituted or unsubstituted aryl group, and the aryl group represented by R ³¹ and the aryl group represented by R ³² may be linked. R ⁴¹ , R ⁴² and R ⁴³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁴¹ and R ⁴² together form a ring structure. R ⁴² and R ⁴³ may together form a ring structure. R ⁵¹ , R ⁵² and R ⁵³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁵¹ and R ⁵² together form a ring structure. R ⁵² and R ⁵³ may be combined to form a ring structure. ]
[5] At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) is any one of the following general formulas (A) to (C). The organic electroluminescence device according to [1], which has a structure represented by:

[In General Formula (A), Z ¹ represents a nitrogen atom, an oxygen atom, a sulfur atom or a silicon atom, and each of A ¹ and A ² independently represents an aromatic ring, a heteroaromatic ring, an aliphatic ring or a non-aromatic heterocyclic ring. It may be formed. In the general formula (B), R ²⁰ represents an atomic group necessary to form a ring structure represented by a hydrogen atom, an aryl group, or A ^4, each independently as A ³ and A ^4, heteroaromatic ring, or A non-aromatic heterocycle may be formed. In the general formula (C), Z ¹ , Z ² , Z ³ and Z ⁴ each independently represent an oxygen atom or a sulfur atom. ]
[6] At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) has any one of the following structures D1 to D13. The organic electroluminescence device according to [1], which is characterized in that

[7] At least one of R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ^{16 in} the general formula (1) is any one of the following general formulas (6) to (9). The organic electroluminescence device according to any one of [1] to [6], which has a structure represented by:

[In the above formula, R ⁶¹ and R ⁶² each independently represents a substituted or unsubstituted aryl group. R ⁷¹ and R ⁷² each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁷¹ and R ⁷² may form a ring structure together. Good. R ⁸¹ , R ⁸² and R ⁸³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁸¹ and R ⁸² together form a ring structure. R ⁸² and R ⁸³ may be combined to form a ring structure. R ⁹¹ represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and Z represents a linking group necessary for forming a heteroaromatic ring other than a triazine ring. ]
[8] At least one of R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ^{16 in} the general formula (1) has any one of the following structures: [1] The organic electroluminescence device according to any one of [6].

[9] The organic electroluminescent element according to any one of [1] to [8], wherein the organic electroluminescent element has a light-emitting layer made of only the compound represented by the general formula (1).
[10] The organic electroluminescent element according to any one of [1] to [8], wherein the compound represented by the general formula (1) is used as a dopant of a light emitting layer.
[11] The organic electroluminescent element according to any one of [1] to [10], wherein the organic layer includes only a light emitting layer.

［一般式（１’）において、Ｒ^１’、Ｒ^２’、Ｒ^３’、Ｒ^４’、Ｒ^５’、Ｒ^６’、Ｒ^７’およびＲ^８’は、各々独立に水素原子または電子供与基であって、少なくとも１つは電子供与基で置換されたアリール基を表す。Ｒ^９’、Ｒ^１０’、Ｒ^１１’、Ｒ^１２’、Ｒ^１３’、Ｒ^１４’、Ｒ^１５’およびＲ^１６’は、各々独立に水素原子またはトリアジノ基以外の電子吸引基であって、少なくとも１つはトリアジノ基以外の電子吸引基を表す。ただし、Ｒ^１’、Ｒ^２’、Ｒ^３’、Ｒ^４’、Ｒ^５’、Ｒ^６’、Ｒ^７’、Ｒ^８’、Ｒ^９’、Ｒ^１０’、Ｒ^１１’、Ｒ^１２’、Ｒ^１３’、Ｒ^１４’、Ｒ^１５’およびＲ^１６’のうちの１１〜１４個は水素原子である。］
［１３］ 一般式（１）のＲ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５、Ｒ^６、Ｒ^７およびＲ^８の少なくとも１つが、下記一般式（２）で表される構造を有することを特徴とする［１２］に記載の化合物。

［一般式（２）において、Ｒ^２１、Ｒ^２２、Ｒ^２３、Ｒ^２４およびＲ^２５は、各々独立に水素原子または電子供与基であって、少なくとも１つは電子供与基を表す。］
［１４］ 一般式（１）のＲ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５、Ｒ^６、Ｒ^７およびＲ^８の少なくとも１つが、下記一般式（３）〜（５）のいずれかで表される構造を有することを特徴とする［１２］に記載の化合物。

［上式において、Ｒ^３１およびＲ^３２は、各々独立に置換もしくは無置換のアリール基を表し、Ｒ^３１が表すアリール基とＲ^３２が表すアリール基は連結していてもよい。Ｒ^４１、Ｒ^４２およびＲ^４３は、各々独立に水素原子、置換もしくは無置換のアルキル基、または置換もしくは無置換のアリール基を表し、Ｒ^４１およびＲ^４２は一緒になって環構造を形成していてもよく、Ｒ^４２およびＲ^４３は一緒になって環構造を形成していてもよい。Ｒ^５１、Ｒ^５２およびＲ^５３は、各々独立に水素原子、置換もしくは無置換のアルキル基、または置換もしくは無置換のアリール基を表し、Ｒ^５１およびＲ^５２は一緒になって環構造を形成していてもよく、Ｒ^５２およびＲ^５３は一緒になって環構造を形成していてもよい。］
［１５］ 一般式（１）のＲ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５、Ｒ^６、Ｒ^７およびＲ^８の少なくとも１つが、下記のいずれかの構造を有することを特徴とする［１２］に記載の化合物。

［１６］ 一般式（１）のＲ^９、Ｒ^１０、Ｒ^１１、Ｒ^１２、Ｒ^１３、Ｒ^１４、Ｒ^１５およびＲ^１６の少なくとも１つが、下記一般式（６）〜（９）のいずれかで表される構造を有することを特徴とする［１２］〜［１５］のいずれか一項に記載の化合物。

［上式において、Ｒ^６１およびＲ^６２は、各々独立に置換もしくは無置換のアリール基を表す。Ｒ^７１およびＲ^７２は、各々独立に水素原子、置換もしくは無置換のアルキル基、または置換もしくは無置換のアリール基を表し、Ｒ^７１およびＲ^７２は一緒になって環構造を形成していてもよい。Ｒ^８１、Ｒ^８２およびＲ^８３は、各々独立に水素原子、置換もしくは無置換のアルキル基、または置換もしくは無置換のアリール基を表し、Ｒ^８１およびＲ^８２は一緒になって環構造を形成していてもよく、Ｒ^８２およびＲ^８３は一緒になって環構造を形成していてもよい。Ｒ^９１は水素原子、置換もしくは無置換のアルキル基、または置換もしくは無置換のアリール基を表し、Ｚはトリアジン環以外のヘテロ芳香環を形成するのに必要な連結基を表す。］
［１７］ 一般式（１）のＲ^９、Ｒ^１０、Ｒ^１１、Ｒ^１２、Ｒ^１３、Ｒ^１４、Ｒ^１５およびＲ^１６の少なくとも１つが、下記のいずれかの構造を有することを特徴とする［１２］〜［１６］のいずれか一項に記載の化合物。

［１８］ ［１２］〜［１７］のいずれか一項に記載の化合物からなる発光材料。[12] A monospirobifluorene compound represented by the following general formula (1 ′).

[In the general formula (1 ′), R ^{1 ′} , R ^{2 ′} , R ^{3 ′} , R ^{4 ′} , R ^{5 ′} , R ^{6 ′} , R ^{7 ′} and R ^{8 ′} are each independently a hydrogen atom or an electron donor. A group, at least one of which represents an aryl group substituted with an electron donating group. R ^{9 ′} , R ^{10 ′} , R ^{11 ′} , R ^{12 ′} , R ^{13 ′} , R ^{14 ′} , R ^{15 ′} and R ^{16 ′} are each independently an electron withdrawing group other than a hydrogen atom or a triazino group, At least one represents an electron withdrawing group other than the triazino group. However, R ^{1 ′} , R ^{2 ′} , R ^{3 ′} , R ^{4 ′} , R ^{5 ′} , R ^{6 ′} , R ^{7 ′} , R ^{8 ′} , R ^{9 ′} , R ^{10 ′} , R ^{11 ′} , R ^{12 ′} , 11 to ^{14 of} R ^{13 ′} , R ^{14 ′} , R ^{15 ′} and R ^{16 ′} are hydrogen atoms. ]
[13] At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) has a structure represented by the following general formula (2). [12] The compound according to [12].

[In General Formula (2), R ²¹ , R ²² , R ²³ , R ²⁴ and R ²⁵ are each independently a hydrogen atom or an electron-donating group, and at least one represents an electron-donating group. ]
[14] At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) is any one of the following general formulas (3) to (5). The compound according to [12], which has a structure represented by:

[In the above formula, R ³¹ and R ³² each independently represent a substituted or unsubstituted aryl group, and the aryl group represented by R ³¹ and the aryl group represented by R ³² may be linked. R ⁴¹ , R ⁴² and R ⁴³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁴¹ and R ⁴² together form a ring structure. R ⁴² and R ⁴³ may together form a ring structure. R ⁵¹ , R ⁵² and R ⁵³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁵¹ and R ⁵² together form a ring structure. R ⁵² and R ⁵³ may be combined to form a ring structure. ]
[15] At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) has one of the following structures: [12] The compound according to [12].

[16] At least one of R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ^{16 in} the general formula (1) is any one of the following general formulas (6) to (9). The compound according to any one of [12] to [15], which has a structure represented by:

[In the above formula, R ⁶¹ and R ⁶² each independently represents a substituted or unsubstituted aryl group. R ⁷¹ and R ⁷² each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁷¹ and R ⁷² may form a ring structure together. Good. R ⁸¹ , R ⁸² and R ⁸³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁸¹ and R ⁸² together form a ring structure. R ⁸² and R ⁸³ may be combined to form a ring structure. R ⁹¹ represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and Z represents a linking group necessary for forming a heteroaromatic ring other than a triazine ring. ]
[17] At least one of R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ^{16 in} the general formula (1) has one of the following structures: [12] The compound according to any one of [16].

[18] A luminescent material comprising the compound according to any one of [12] to [17].

  The organic electroluminescence device of the present invention has the characteristics that the luminous efficiency is high and a thin light emitting layer can be easily formed. Moreover, the compound of this invention is very useful as a luminescent material of such an organic electroluminescent element.

It is a schematic sectional drawing which shows the layer structure of the organic electroluminescent element of an Example. 3 is a graph showing current density-voltage-luminance characteristics in Example 1. 4 is a graph showing current density-external quantum efficiency characteristics in Example 1. 2 is an emission spectrum in Example 1. 2 is an energy level diagram in Example 1. FIG. It is an emission spectrum of the solution in Example 51. 42 is a graph showing PL transient attenuation in Example 51. 42 is a graph showing PL transient attenuation in Example 58.

  Hereinafter, the contents of the present invention will be described in detail. The description of the constituent elements described below may be made based on typical embodiments and specific examples of the present invention, but the present invention is not limited to such embodiments and specific examples. In the present specification, a numerical range represented by using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

[Compound represented by general formula (1)]
The organic electroluminescence device of the present invention is characterized in that the light emitting layer contains a monospirobifluorene compound represented by the following general formula (1). Therefore, the monospirobifluorene compound represented by the general formula (1) will be described first.

R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ in the general formula (1) each independently represent a hydrogen atom or an electron donating group. However, at least one of these represents an electron donating group. When two or more of these represent an electron donating group, the two or more electron donating groups may be the same or different. Preferred is the case where they are identical. Among R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ , those representing an electron donating group are R ² , R ³ , R ⁴ , R ⁵ , R ⁶ and R ^7. Or any one of R ² , R ³ , R ⁶ and R ⁷ is more preferable. More preferably, any one or two of R ² , R ³ , R ⁶ and R ⁷ , and in the case of ^two , any one of R ² and R ³ , and any of R ⁶ and R ⁷ It is preferable that it is one.

The electron donating groups represented by R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ donate electrons to the spirobifluorene ring when bonded to the spirobifluorene ring. It is a group having properties. The electron donating group may be an aromatic group, a heteroaromatic group, or an aliphatic group, or may be a group in which two or more of these are combined. Examples of the electron donating group may be an alkyl group (which may be linear, branched or cyclic, preferably 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms, specific examples As a methyl group, an ethyl group, a propyl group, a pentyl group, a hexyl group, and an isopropyl group) or an alkoxy group (straight, branched, or cyclic), preferably 1 carbon atom -6, more preferably 1 to 3 carbon atoms, and specific examples include a methoxy group), an amino group or a substituted amino group (preferably an amino group substituted with an aromatic group, Examples include diphenylamino group, anilyl group, and tolylamino group), aryl group (which may be monocyclic or fused ring, and may be further substituted with aryl group. Group, biphenyl group and terphenyl group), an electron donating group containing a heterocyclic structure (preferably an electron donating group containing a heterocyclic structure containing a nitrogen atom or a sulfur atom, and specific examples include thiophenyl A benzothiophenyl group, a julolidyl group, a pyrrolyl group, an indolyl group, and a carbazolyl group). For example, the electron donating group preferably has a σp value of −0.06 or less, more preferably −0.14 or less, and even more preferably −0.28 or less.

At least ^{one of} R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ is preferably an aryl group substituted with an electron donating group. The aryl group here may be composed of one aromatic ring, or may have a structure in which two or more aromatic rings are fused. The aryl group preferably has 6 to 22 carbon atoms, more preferably 6 to 18 carbon atoms, still more preferably 6 to 14 carbon atoms, and more preferably 6 to 10 carbon atoms (ie, phenyl group, 1-naphthyl). Group, 2-naphthyl group) is more preferred, and phenyl group is most preferred. In addition, the electron donating group substituted for the aryl group preferably has the above-mentioned σp value.

More preferably, at ^{least one of} R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ is a group represented by the following general formula (2).

In the general formula (2), R ²¹ , R ²² , R ²³ , R ²⁴ and R ²⁵ each independently represent a hydrogen atom or an electron donating group. However, at least one of these represents an electron donating group. The electron donating group here preferably has the above-mentioned σp value. Among R ²¹ , R ²² , R ²³ , R ²⁴ and R ²⁵ , it is preferable that R ²² and R ²⁴ are electron donating groups, or R ²³ is an electron donating group, and R ²³ is an electron donating group. More preferably.

At least ^{one of} R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ has a structure represented by any one of the following general formulas (3) to (5). It is more preferable to have it.

In the above formula, R ³¹ and R ³² each independently represent a substituted or unsubstituted aryl group, and the aryl group represented by R ³¹ and the aryl group represented by R ³² may be linked. R ⁴¹ , R ⁴² and R ⁴³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁴¹ and R ⁴² together form a ring structure. R ⁴² and R ⁴³ may together form a ring structure. R ⁵¹ , R ⁵² and R ⁵³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁵¹ and R ⁵² together form a ring structure. R ⁵² and R ⁵³ may be combined to form a ring structure.
The ring structure formed by R ⁴¹ and R ⁴² , R ⁴² and R ⁴³ , R ⁵¹ and R ⁵² , and R ⁵² and R ⁵³ together may be an aromatic ring, a heteroaromatic ring, or an aliphatic ring. It is preferably an aromatic ring or a heteroaromatic ring, more preferably an aromatic ring. Specific examples of the ring structure include a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, and the like.

The aryl group as used herein may be composed of one aromatic ring or may have a structure in which two or more aromatic rings are fused. The aryl group preferably has 6 to 22 carbon atoms, more preferably 6 to 18 carbon atoms, still more preferably 6 to 14 carbon atoms, and more preferably 6 to 10 carbon atoms (ie, phenyl group, 1-naphthyl). Group, 2-naphthyl group) is even more preferred.
The alkyl group as used herein may be linear, branched, or cyclic. Preference is given to a linear or branched alkyl group. The alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 12, more preferably 1 to 6, and more preferably 1 to 3 (that is, a methyl group, an ethyl group, n-propyl group, isopropyl group) is even more preferable. Examples of the cyclic alkyl group include a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group.
Examples of the substituent for the aryl group and the alkyl group include an alkyl group, an aryl group, an alkoxy group, and an aryloxy group. Descriptions and preferred ranges of alkyl groups and aryl groups that can be employed as substituents are the same as described above. Further, the alkoxy group that can be employed as the substituent may be linear, branched, or cyclic. Preferred is a linear or branched alkoxy group. The number of carbon atoms of the alkoxy group is preferably 1 to 20, more preferably 1 to 12, still more preferably 1 to 6, and 1 to 3 (that is, a methoxy group, an ethoxy group, n-propoxy group, isopropoxy group) are even more preferable. Examples of the cyclic alkoxy group include a cyclopentyloxy group, a cyclohexyloxy group, and a cycloheptyloxy group. In addition, the aryloxy group that can be employed as a substituent may be composed of one aromatic ring or may have a structure in which two or more aromatic rings are fused. The aryloxy group preferably has 6 to 22 carbon atoms, more preferably 6 to 18 carbon atoms, still more preferably 6 to 14 carbon atoms, and 6 to 10 carbon atoms (that is, phenyloxy group, 1 -Naphtyloxy group, 2-naphthyloxy group) is even more preferable.
Examples of the substituent for the alkyl group and aryl group in the general formulas (3) to (5) include a group exhibiting an electron donating property.

As an electron donating group represented by at least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^8, any one of the following general formulas (A) to (C) An electron donating group containing a skeleton represented by

In the general formula (A), Z ¹ represents a nitrogen atom, an oxygen atom, a sulfur atom or a silicon atom. In addition, A ¹ and A ² in the general formula (A) may each independently form an aromatic ring, a heteroaromatic ring, an aliphatic ring or a non-aromatic heterocycle, or may not form these rings. May be. For example, when Z ¹ is a nitrogen atom and A ¹ and A ² both form a benzene ring, the general formula (A) represents a carbazole skeleton. When A ¹ forms a benzene ring and A ² does not form a ring structure, general formula (A) represents an indole skeleton. Furthermore, when both A ¹ and A ² do not form a ring structure, the general formula (A) represents a pyrrole skeleton. As another example, when Z ¹ is a silicon atom and A ¹ and A ² both form a benzene ring, the general formula (A) represents a silafluoroene skeleton. Further, when Z ¹ is a sulfur atom, when A ¹ forms a benzene ring and A ² does not form a ring structure, the general formula (A) represents a benzothiophene skeleton.
When A ¹ and A ^{2 in} the general formula (A) form a ring structure, the ring structure may be a fused ring structure in which a plurality of rings are fused. Such a fused ring may be a fused aromatic ring, a fused heteroaromatic ring, a fused alicyclic ring, Furthermore, it may be a fusion of different types of rings such as an aromatic ring and a heteroaromatic ring, and is not particularly limited. Moreover, the rings to be fused may be the same or different. For example, when Z ¹ is a sulfur atom, A ¹ forms a ring structure in which a furan ring is fused to a benzene ring, and A ² does not form a ring structure, the general formula (A) is benzodifuran. Represents the skeleton.
The ring structure that A ¹ and A ² of the general formula (A) can form is preferably an aromatic ring or a heteroaromatic ring, and more preferably an aromatic ring.

The aromatic ring that A ¹ and A ² can form is a benzene ring. Examples of the heteroaromatic ring that A ¹ and A ² can form include a furan ring, a thiophene ring, a pyrrole ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, an imidazole ring, a pyrazole ring, a furan ring, and a pyridine ring. , Pyridazine ring, pyrimidine ring and pyrazine ring. Examples of the aliphatic ring that A ¹ and A ² can form include a cyclopentene ring, a cyclohexene ring, a cycloheptene ring, a cyclopentadiene ring, a cyclohexadiene ring, a cycloheptadiene ring, and a cycloheptatriene ring. Examples of the non-aromatic heterocycle that A ¹ and A ² can form include a pyrroline ring, an imidazoline ring, and a pyrazoline ring. Examples of the fused ring that A ¹ and A ² can form include, for example, naphthalene ring, anthracene ring, phenanthrene ring, pyrene ring, indole ring, isoindole ring, indazole ring, chromene ring, quinoline ring, isoquinoline ring, cinnoline ring, Examples thereof include a quinazoline ring, a quinoxaline ring, a phthalazine ring, a pteridine ring, a xanthene ring, a carbazole ring, a phenanthridine ring, an acridine ring, a phenazine ring, and a phenanthroline ring.

In the general formula (B), R ²⁰ represents a hydrogen atom, an aryl group, or an atomic group necessary for forming a ring structure represented by A ⁴ . In addition, A ³ and A ⁴ in the general formula (B) may each independently form a heteroaromatic ring or a non-aromatic heterocycle, or may not form these rings. For specific examples of the heteroaromatic ring or non-aromatic heterocycle that A ³ and A ⁴ can form, see the specific examples of the heteroaromatic ring or non-aromatic heterocycle that A ¹ and A ² can form above. be able to. In addition, the aryl group that R ²⁰ can take may be a single aromatic ring or a structure in which two or more aromatic rings are fused. The number of carbon atoms constituting the aryl group is preferably 6-22, more preferably 6-18, further preferably 6-14, and 6-10 (that is, benzene ring, naphthalene). Ring) is even more preferred, and a phenyl group is most preferred.

As an example of the structure represented by the general formula (B), for example, when R ²⁰ is a hydrogen atom and A ³ does not form a ring structure, the general formula (B) represents an aniline skeleton. When R ²⁰ is a benzene ring and A ³ does not form a ring structure, the general formula (B) represents a diphenylamine skeleton. Further, when R ²⁰ is an atomic group necessary for forming a piperidine ring and A ³ forms a piperidine ring, the general formula (B) represents a julolidine skeleton.

In the general formula (C), Z ¹ , Z ² , Z ³ and Z ⁴ each independently represent an oxygen atom or a sulfur atom. These atoms may be the same or different, but are preferred when they are the same.

Preferred specific examples of the electron donating group represented by at least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are listed below. However, the electron donating group that can be employed in the general formula (1) is not limitedly interpreted by these specific examples.

R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ in the general formula (1) each independently represent an electron withdrawing group other than a hydrogen atom or a triazino group. However, at least one of these represents an electron withdrawing group other than the triazino group. When two or more of these represent an electron withdrawing group, the two or more electron withdrawing groups may be the same or different. Preferred is the case where they are identical. Among R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ , those representing an electron withdrawing group are R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ and R ^15. Or any one of R ¹⁰ , R ¹¹ , R ^14, and R ¹⁵ is more preferable. More preferably, any one or two of R ¹⁰ , R ¹¹ , R ¹⁴ and R ¹⁵ , and in the case of two, any one of R ¹⁰ and R ¹¹ , and any of R ¹⁴ and R ¹⁵ It is preferable that it is one.

The electron-withdrawing group represented by R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ^15, and R ^{16 in the} general formula (1) is a spirobifluorene when bonded to the spirobifluorene ring. It is a group having a property of attracting from a ring. The electron withdrawing group may be an aromatic group, a heteroaromatic group, or an aliphatic group, or may be a group in which two or more of these are combined. Examples of the electron-withdrawing group include a nitro group and a perfluoroalkyl group (preferably having 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms, and specific examples include a trifluoromethyl group). Sulfonyl group, electron-withdrawing group containing a heterocyclic structure (preferably an electron-withdrawing group containing a heterocyclic structure containing a nitrogen atom or a sulfur atom, and specific examples include oxadiazolyl group, benzothiadiazolyl group, tetrazolyl group, thiazolyl group An imidazolyl group, etc., but a triazino group is excluded.), A group containing a phosphine oxide structure, a cyano group, and the like. Examples of the group of electron withdrawing groups include a group in which a cyano group is removed from the specific examples of the electron withdrawing groups. For example, the electron withdrawing group preferably has a σp value of 0.02 or more, more preferably 0.34 or more, and even more preferably 0.62 or more.

At least one of R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ has a structure represented by any one of the following general formulas (6) to (9). It is preferable to have.

In the above formula, R ⁶¹ and R ⁶² each independently represents a substituted or unsubstituted aryl group. R ⁷¹ and R ⁷² each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁷¹ and R ⁷² may form a ring structure together. Good. R ⁸¹ , R ⁸² and R ⁸³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁸¹ and R ⁸² together form a ring structure. R ⁸² and R ⁸³ may be combined to form a ring structure. R ⁹¹ represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and Z represents a linking group necessary for forming a heteroaromatic ring other than a triazine ring. The connecting chain of Z may be composed only of carbon atoms, may be composed only of heteroatoms, or may be a mixture of carbon atoms and heteroatoms. As a hetero atom, a nitrogen atom is preferable. The connecting chain is preferably 2 to 4 atoms long, more preferably 2 or 3 atoms long. Examples of the elements constituting the connecting chain include those consisting only of carbon atoms, those consisting only of nitrogen atoms, and those consisting of combinations of carbon atoms and sulfur atoms.
For the explanation and preferred range of the aryl group and alkyl group here, refer to the explanation and preferred range of the aryl group and alkyl group that can be taken by R ⁴¹ , R ⁴² , R ⁴³ , R ⁵¹ , R ⁵² and R ^53. Can do. However, examples of the substituent of the aryl group or the alkyl group in the general formulas (6) to (9) include an electron-withdrawing group in addition to the alkyl group, the aryl group, the alkyloxy group, and the aryloxy group. it can.

Preferred specific examples of the electron withdrawing group represented by at least one of R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ are listed below. However, the electron withdrawing group that can be employed in the general formula (1) is not limitedly interpreted by these specific examples.

R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ^{15 in the} general formula (1) And 11 to 14 of R ¹⁶ are hydrogen atoms. At this time, 4 to 7 of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are preferably hydrogen atoms, and 6 or 7 are hydrogen atoms. More preferably. Further, 4 to 7 of R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ are preferably hydrogen atoms, and 6 or 7 are hydrogen atoms. It is more preferable. As a preferred example, ^{seven of} R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are hydrogen atoms, and R ⁹ , R ¹⁰ , R ¹¹ , R ^A compound in which 7 of ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ are hydrogen atoms, or R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ Examples include compounds in which six of them are hydrogen atoms and six of R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ are hydrogen atoms. it can.
In addition, the compound represented by the general formula (1) of the present invention is a monospirobifluorene compound. Therefore, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ Is not a group containing a spirobifluorene ring.

Among the compounds represented by the above general formula (1), the compounds represented by the following general formula (1 ′) are novel compounds.

In the general formula (1 ′), R ^{1 ′} , R ^{2 ′} , R ^{3 ′} , R ^{4 ′} , R ^{5 ′} , R ^{6 ′} , R ^{7 ′} and R ^{8 ′} each independently represents a hydrogen atom or an electron donating group. Wherein at least one represents an aryl group substituted with an electron donating group. R ^{9 ′} , R ^{10 ′} , R ^{11 ′} , R ^{12 ′} , R ^{13 ′} , R ^{14 ′} , R ^{15 ′} and R ^{16 ′} are each independently an electron withdrawing group other than a hydrogen atom or a triazino group, At least one represents an electron withdrawing group other than the triazino group. However, R ^{1 ′} , R ^{2 ′} , R ^{3 ′} , R ^{4 ′} , R ^{5 ′} , R ^{6 ′} , R ^{7 ′} , R ^{8 ′} , R ^{9 ′} , R ^{10 ′} , R ^{11 ′} , R ^{12 ′} , 11 to ^{14 of} R ^{13 ′} , R ^{14 ′} , R ^{15 ′} and R ^{16 ′} are hydrogen atoms.
For the explanation and preferred range of the electron donating group, the aryl group substituted with the electron donating group and the electron withdrawing group in the general formula (1 ′), the corresponding description in the general formula (1) can be referred to.

  The molecular weight of the compound represented by the general formula (1) is preferably 1500 or less, and preferably 1200 or less when it is intended to use an organic layer containing the compound by forming a film by a vapor deposition method, for example. More preferably, it is more preferably 1000 or less, and even more preferably 800 or less. About the lower limit of molecular weight, it can be set as 350 or more, for example.

  Hereinafter, specific examples of the compound represented by the general formula (1) will be exemplified, but the compound represented by the general formula (1) that can be used in the present invention is limitedly interpreted by these specific examples. It shouldn't be. In the table, D1 to D3 represent an aryl group substituted with the electron donating group, A1 to A4 represent the electron withdrawing group, and H represents a hydrogen atom.

[Synthesis Method of Compound Represented by General Formula (1)]
The method for synthesizing the compound represented by the general formula (1) is not particularly limited. The compound represented by the general formula (1) can be synthesized by appropriately combining known synthesis methods and conditions.
For example, a preferred synthesis method includes a synthesis method represented by the following scheme. Here, a method for synthesizing a compound of the general formula (15) in which one fluorene skeleton is substituted with one aryl group substituted with an electron donating group and the other fluorene skeleton is substituted with an electron withdrawing group is given as a typical example. Yes.

  In the above scheme, the boronic acid represented by the general formula (12) is first reacted with the dihalogenospirobifluorene represented by the general formula (11). X in the general formula (11) represents a halogen atom. Specific examples include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. A chlorine atom, a bromine atom, and an iodine atom are preferable, and a bromine atom is more preferable. D in the general formula (12) represents an electron donating group. In this reaction, the conditions are controlled so that the compound represented by the general formula (12) reacts only with one X of the general formula (11). For example, the production of a disubstituted product can be suppressed by reducing the amount of the compound represented by the general formula (12) to a small amount. The compound represented by the general formula (13) obtained by this reaction is further reacted with a boronic acid represented by the general formula (14). A in the general formula (14) represents an electron withdrawing group. By this reaction, the target product represented by the general formula (15) can be obtained. For the reaction between the halogenospirobifluorene and the boronic acid in the first step and the second step, reaction conditions that are usually used can be employed.

  The boronic acid used in the first and second steps of the above scheme may be interchanged. That is, the boronic acid represented by the general formula (14) may be reacted in the first step, and the boronic acid represented by the general formula (12) may be reacted in the second step.

The method of synthesizing the compound represented by the general formula (1) other than the general formula (15) can be synthesized according to the method of the above scheme. Further, depending on the type of substituent to be introduced into halogenospirbifluorene, it is also possible to utilize a reaction specific to the substituent. For example, when a diphenylphosphinyl group is to be introduced, a diphenylphosphino group is first introduced by reacting halogenospirbifluorene with chlorodiphenylphosphine, and then oxidized with hydrogen peroxide or the like to oxidize diphenylphosphinyl group. The fino group can be converted to a diphenylphosphinyl group.
The details of these reactions can be referred to the synthesis examples described below. The compound represented by the general formula (1) can also be synthesized by combining other known synthesis reactions.

[Organic electroluminescence device]
The organic electroluminescence device of the present invention has a structure having an anode, a cathode, and an organic layer between the anode and the cathode. The organic layer includes at least a light emitting layer, and may consist of only the light emitting layer, or may have one or more organic layers in addition to the light emitting layer. The organic electroluminescent element of this invention contains the compound represented by General formula (1) in a light emitting layer.
In the light emitting layer, the compound represented by the general formula (1) is included as a host material, and may constitute the light emitting layer together with a dopant material having another structure, or represented by the general formula (1). Such a compound is included as a dopant material, and may constitute a light emitting layer together with a host material having another structure. Moreover, the light emitting layer may be comprised only with the compound represented by General formula (1).

  The compound represented by the general formula (1) has high thin film forming ability, is stable in the neat thin film state, and can realize excellent luminous efficiency in the neat thin film state. In addition, the HOMO of the compound represented by the general formula (1) has a relatively preferable energy level with respect to a commonly used anode, and the LUMO of the compound represented by the general formula (1) is It has a relatively favorable energy level with respect to a commonly used cathode. For example, the energy level diagram of Compound 1 is as shown in FIG. 5 and can be preferably combined with ITO or LiF which is frequently used as an electrode. Therefore, a single-layer organic electroluminescence device having a simple structure in which a neat thin film layer of a compound represented by the general formula (1) is formed as a light emitting layer on an anode and a cathode is formed thereon. Even so, relatively high luminous efficiency can be realized. Therefore, if the compound represented by the general formula (1) is used, an organic electroluminescence device having a simpler structure than the conventional one can be easily manufactured, and the cost may be reduced.

  The organic electroluminescence device of the present invention has a structure in which at least an anode, an organic layer, and a cathode are laminated. In the case of a single layer type organic electroluminescence element, only the light emitting layer is provided between the anode and the cathode, but the organic electroluminescence element of the present invention includes those having a plurality of organic layers. The organic layers other than the light-emitting layer are called a hole injection layer, a hole transport layer, an electron block layer, a light-emitting layer, a hole block layer, an electron transport layer, an electron injection layer, or the like depending on their functions. They can be used in combination. Specific configuration examples including the anode and cathode include: anode / light emitting layer / cathode, anode / hole injection layer / light emitting layer / cathode, anode / hole injection layer / hole transport layer / light emitting layer / cathode, anode / hole injection. Layer \ light emitting layer \ electron injection layer \ cathode, anode \ hole injection layer \ hole transport layer \ light emission layer \ electron injection layer \ cathode, anode \ hole injection layer \ light emission layer \ electron transport layer \ electron injection layer \ cathode, anode \ Hole injection layer \ Hole transport layer \ Light emitting layer \ Electron transport layer \ Electron injection layer \ Cathode, anode \ Light emitting layer \ Electron injection layer \ Cathode, anode \ Light emitting layer \ Electron injection layer \ Electron transport layer \ Cathode, anode \ A hole injection layer \ light emitting layer \ hole blocking layer \ electron injection layer \ cathode can be mentioned. These anode / organic layer / cathode structures can be formed on a substrate. In addition, the structure which can be employ | adopted by this invention is not limited to these. Further, the compound represented by the general formula (1) is particularly preferably used in the light emitting layer, but the use of the compound represented by the general formula (1) as a charge transport material or the like in an organic layer other than the light emitting layer is excluded. Not what you want.

  When manufacturing each organic layer and electrode which comprise the organic electroluminescent element of this invention, a well-known manufacturing method can be selected suitably and can be employ | adopted. For each organic layer or electrode, various materials employed in known organic electroluminescence elements can be selected and used. Furthermore, the organic electroluminescence element of the present invention can be modified as necessary with various modifications that can be easily conceived from known techniques and known techniques. Hereinafter, typical materials constituting the organic electroluminescence element will be described. However, materials that can be used for the organic electroluminescence element of the present invention are not limitedly interpreted by the following description.

(substrate)
The substrate functions as a support for supporting the structure of the anode / organic layer / cathode and also functions as a substrate in manufacturing the structure of the anode / organic layer / cathode. The substrate may be made of a transparent material, or may be made of a translucent or opaque material. In the case where light emission is extracted from the anode side, it is preferable to use a transparent substrate. Examples of the material constituting the substrate include glass, quartz, metal, polycarbonate, polyester, polymethacrylate, and polysulfone. If a flexible substrate is used, a flexible organic electroluminescence element can be obtained.

(anode)
The anode has a function of injecting holes toward the organic layer. As such an anode, a material having a high work function is preferably used. For example, a material having 4 eV or more is preferably used. Specifically, metal (for example, aluminum, gold, silver, nickel, palladium, platinum), metal oxide (for example, indium oxide, tin oxide, zinc oxide, a mixture of indium oxide and tin oxide [ITO], zinc oxide) And a mixture of indium oxide [IZO]), metal halide (for example, copper iodide), and carbon black. It is also possible to use conductive polymers such as polyaniline, poly (3-methylthiophene), and polypyrrole. In the case of taking out light emission from the anode side, it is preferable to use a material having high transmittance with respect to light emission such as ITO or IZO. The transmittance is preferably 10% or more, more preferably 50% or more, and further preferably 80% or more. The thickness of the anode is usually 3 nm or more and preferably 10 nm or more. The upper limit can be set to, for example, 1 μm or less, but may be thicker when transparency is not required for the anode. For example, the anode may have the above function as a substrate. The anode can be formed, for example, by vapor deposition, sputtering, or coating. When a conductive polymer is used for the anode, it is also possible to form the anode on the substrate using an electrolytic polymerization method. After the formation of the anode, surface treatment can be performed for the purpose of improving the hole injection function. Specific examples of the surface treatment include plasma treatment (for example, argon plasma treatment, oxygen plasma treatment), UV treatment, ozone treatment, and the like.

(Hole injection layer and hole transport layer)
The hole injection layer has a function of transporting holes from the anode to the light emitting layer side. Since the hole injection layer is generally formed on the anode, the hole injection layer is preferably a layer having excellent adhesion to the anode surface. For this reason, it is preferable to be comprised with the material with high thin film formation ability. The hole transport layer has a function of transporting holes to the light emitting layer side. The hole transport layer is made of a material excellent in hole transportability.
For the hole injection layer and the hole transport layer, a hole transport material having high hole mobility and low ionization energy is used. An ionization energy of, for example, 4.5 to 6.0 eV can be preferably selected. As the hole transport material, various materials that can be used for the hole injection layer or the hole transport layer of the organic electroluminescence element can be appropriately selected and used. The hole transport material may be a polymer material having a repeating unit or a low molecular compound.

  Examples of hole transport materials include aromatic tertiary amine compounds, styrylamine compounds, oxadiazole derivatives, imidazole derivatives, triazole derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazoles Derivatives, polyarylalkane derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, silane polymers, aniline copolymers, thiophene polymers, and porphyrin compounds can be given.

Preferred examples of the hole transporting material include aromatic tertiary amine compounds. Specifically, triphenylamine, tolylamine, N, N′-diphenyl-N, N ′-(3-methylphenyl) -1 , 1′-biphenyl-4,4′-diamine, N, N, N ′, N ′-(4-methylphenyl) -1,1′-phenyl-4,4′-diamine, N, N, N ′ , N ′-(4-methylphenyl) -1,1′-biphenyl-4,4′-diamine, N, N′-diphenyl-N, N′-dinaphthyl-1,1′-biphenyl-4,4 ′ -Diamine, N, N '-(methylphenyl) -N, N'-(4-n-butylphenyl) -phenanthrene-9,10-diamine, N, N-bis (4-di-4-tolylaminophenyl) ) -4-phenyl-cyclohexane, N, N′-bis (4′-diphenyl) Mino-4-biphenylyl) -N, N′-diphenylbenzidine, N, N′-bis (4′-diphenylamino-4-phenyl) -N, N′-diphenylbenzidine, N, N′-bis (4 ′) -Diphenylamino-4-phenyl) -N, N'-di (1-naphthyl) benzidine, N, N'-bis (4'-phenyl (1-naphthyl) amino-4-phenyl) -N, N'- And diphenylbenzidine, N, N′-bis (4′-phenyl (1-naphthyl) amino-4-phenyl) -N, N′-di (1-naphthyl) benzidine, and the like. In addition, phthalocyanine compounds can also be mentioned as preferable hole transport materials, and specifically, H ₂ Pc, CuPc, CoPc, NiPc, ZnPc, PdPc, FePc, MnPc, ClAlPc, ClGaPc, ClInPc, ClSnPc, Cl ₂ SiPc , (HO) AlPc, (HO) GaPc, VOPc, TiOPc, MoOPc, and GaPc-O-GaPc [Pc represents phthalocyanine]. Further, metal oxides such as poly (ethylenedioxy) thiophene (PEDOT) and molybdenum oxide, and known aniline derivatives can also be preferably used.

  As the hole transport material used in the present invention, only one kind may be selected and used in one layer, or two or more kinds may be used in combination in one layer. The hole injection layer and the hole transport layer can be formed by, for example, a vapor deposition method, a sputtering method, or a coating method. The thickness of the hole injection layer or the hole transport layer is usually 3 nm or more, and preferably 10 nm or more. The upper limit value can be set to 5 μm or less, for example.

(Light emitting layer)
The light emitting layer of the organic electroluminescence device of the present invention may contain a host material and a dopant material, or may consist of only a single material. The compound represented by the general formula (1) of the present invention can be used as a host material, a dopant material, or a single material constituting the light emitting layer.
When the light emitting layer contains a host material and a dopant material, the dopant material is preferably used at 10% by weight or less, more preferably 2% by weight or less, in order to prevent concentration quenching. As the dopant material and the host material, one kind of material may be used alone, or two or more kinds of materials may be used in combination. Doping can be performed by co-evaporation of a host material and a dopant material. At this time, the host material and the dopant material may be mixed in advance and then simultaneously deposited.

Examples of the host material used for the light emitting layer include quinolinol derivative metal complexes, oxadiazole derivatives, distyrylarylene derivatives, and diphenylanthracene derivatives. In addition to these, materials proposed as host materials for the light emitting layer can be appropriately selected and used.
The dopant material can be selected in consideration of the wavelength to be emitted. For example, a wide variety of materials such as an isobenzofuran derivative, a perylene derivative, a distyrylarylene derivative, and a carbazole derivative can be used. In addition, a phosphorescent light emitting material, a heat activated delayed fluorescent material, an exciplex light emitting material, and the like can be appropriately selected and used.

Examples of phosphorescent materials include various conventionally known metal complexes. Examples of phosphorescent materials include Irr complexes such as Flrpic, FCNIr, Ir (dbfmi), FIr6, Ir (fbppz) ₂ (dfbdp), and FIrN4, and [Cu (dnbp) (DPEPhos)] BF ₄ described later. [Cu (dppb) (DPEPhos)] BF ₄ , [Cu (μ-l) dppb] ₂ , [Cu (μ-Cl) DPEphos] ₂ , Cu (2-tzq) (DPEPhos), [Cu (PNP) )] ₂ , compound 1001, Cu complexes such as Cu (Bpz ₄ ) (DPEPhos), and Pt complexes such as FPt and Pt-4 can be mentioned as preferred examples. These structures are shown below.

  Although typical phosphorescent materials have been described above, the phosphorescent materials that can be used in the present invention are not limited to these, and are known as long as they satisfy the formulas (A) and (B). A light emitting material can also be used. Main light emitting materials are described in, for example, Chapter 9 of CMC Publishing, “Device Physics / Material Chemistry / Device Application of Organic EL”.

As the heat activated delayed fluorescent material, for example, the following PIC-TRZ, and the like are preferable and ^{[Cu (PNP- t Bu)]} 2.

Preferred examples of the exciplex light emitting material include m-MTDATA and PBD, PyPySPyPy and NPB, and PPSPP and NPB described below.

(Hall block layer)
The hole blocking layer has a function of preventing holes passing through the light emitting layer from moving to the cathode side. It is preferably formed between the light emitting layer and the organic layer on the cathode side. Examples of the organic material forming the hole blocking layer include an aluminum complex compound, a gallium complex compound, a phenanthroline derivative, a silole derivative, a quinolinol derivative metal complex, an oxadiazole derivative, and an oxazole derivative. Specifically, bis (8-hydroxyquinolinate) (4-phenylphenolate) aluminum, bis (2-methyl-8-hydroxyquinolinate) (4-phenylphenolate) gallium, 2,9-dimethyl Examples include -4,7-diphenyl-1,10-phenanthroline (BCP). For the hole block layer, one type of organic material may be selected and used alone, or two or more types may be used in combination. The hole block layer can be formed by, for example, a vapor deposition method, a sputtering method, or a coating method. The thickness of the hole block layer is usually 3 nm or more, and preferably 10 nm or more. The upper limit value can be set to 5 μm or less, for example.

(Electron injection layer and electron transport layer)
The electron injection layer has a function of transporting electrons from the cathode to the light emitting layer. Since the electron injection layer is generally formed so as to be in contact with the cathode, it is preferably a layer having excellent adhesion to the cathode surface. The electron transport layer has a function of transporting electrons to the light emitting layer side. The electron transport layer is made of a material having excellent electron transport properties.
For the electron injection layer and the electron transport layer, an electron transport material having high electron mobility and high ionization energy is used. As the electron transport material, various materials that can be used for the electron injection layer or the electron transport layer of the organic electroluminescence element can be appropriately selected and used. The electron transport material may be a polymer material having a repeating unit or a low molecular compound.

Examples of electron transport materials include fluorenone derivatives, anthraquinodimethane derivatives, diphenoquinone derivatives, thiopyran dioxide derivatives, oxazole derivatives, thiazole derivatives, oxadiazole derivatives, triazole derivatives, imidazole derivatives, perylenetetracarboxylic acid derivatives, quinoxaline derivatives. , Fluorenylidenemethane derivatives, anthraquinodimethane derivatives, anthrone derivatives and the like. Specific examples of preferred electron transport materials include 2,5-bis (1-phenyl) -1,3,4-oxazole, 2,5-bis (1-phenyl) -1,3,4-thiazole, 2,5 -Bis (1-phenyl) -1,3,4-oxadiazole, 2- (4'-tert-butylphenyl) -5- (4 "-biphenyl) 1,3,4-oxadiazole, 2, 5-bis (1-naphthyl) -1,3,4-oxadiazole, 1,4-bis [2- (5-phenyloxadiazolyl)] benzene, 1,4-bis [2- (5-phenyl) Oxadiazolyl) -4-tert-butylbenzene], 2- (4′-tert-butylphenyl) -5- (4 ″ -biphenyl) -1,3,4-thiadiazole, 2,5-bis (1- Naphthyl) -1,3,4-thiadiazole, 1,4-bis [2- (5 Phenylthiadiazolyl)] benzene, 2- (4′-tert-butylphenyl) -5- (4 ″ -biphenyl) -1,3,4-triazole, 2,5-bis (1-naphthyl) -1, 3,4-triazole, 1,4-bis [2- (5-phenyltriazolyl)] benzene, 8-hydroxyquinolinate lithium, bis (8-hydroxyquinolinato) zinc, bis (8-hydroxyquinolinate) Nato) copper, bis (8-hydroxyquinolinato) manganese, tris (8-hydroxyquinolinato) aluminum, tris (2-methyl-8-hydroxyquinolinato) aluminum, tris (8-hydroxyquinolinato) Gallium, bis (10-hydroxybenzo [h] quinolinato) beryllium, bis (10-hydroxybenzo [h] quinolinato) zinc, bi (2-methyl-8-quinolinato) chlorogallium, bis (2-methyl-8-quinolinato) (o-cresolate) gallium, bis (2-methyl-8-quinolinato) (1-naphtholato) aluminum, bis (2 -Methyl-8-quinolinato) (2-naphtholato) gallium and the like.
As the electron transport material used in the present invention, only one kind may be selected and used in one layer, or two or more kinds may be used in combination in one layer. The electron injection layer and the electron transport layer can be formed by, for example, a vapor deposition method, a sputtering method, or a coating method. The thickness of the electron injection layer or the electron transport layer is usually 3 nm or more, and preferably 10 nm or more. The upper limit value can be set to 5 μm or less, for example.

(cathode)
The cathode has a function of injecting electrons toward the organic layer. As such a cathode, a material having a low work function is preferably used. For example, a material having 4 eV or less is preferably used. Specifically, a metal (for example, tin, magnesium, indium, calcium, aluminum, silver) and an alloy (for example, an aluminum-lithium alloy, a magnesium-silver alloy, a magnesium-indium alloy) can be mentioned. When light emission is taken out from the cathode side, it is preferable to use a material having high transmittance. The transmittance is preferably 10% or more, more preferably 50% or more, and further preferably 80% or more. The thickness of the cathode is usually 3 nm or more, and preferably 10 nm or more. The upper limit value can be set to 1 μm or less, for example, but may be thicker if the cathode is not required to be transparent. The cathode can be formed, for example, by vapor deposition or sputtering. A protective layer is preferably formed on the cathode in order to protect the cathode. Such a protective layer is preferably a layer made of a stable metal having a high work function. For example, a metal layer such as aluminum, silver, copper, nickel, chromium, gold, or platinum can be formed.

  The organic electroluminescence device of the present invention can be further applied to various uses. For example, it is possible to produce an organic electroluminescence display device using the organic electroluminescence element of the present invention. For details, see “Organic EL Display” (Ohm Co., Ltd.) written by Shizushi Tokito, Chiba Adachi and Hideyuki Murata. ) Can be referred to. In particular, the organic electroluminescence device of the present invention can be applied to organic electroluminescence illumination that is in great demand.

  The features of the present invention will be described more specifically with reference to synthesis examples, test examples, and production examples. The following materials, processing details, processing procedures, and the like can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below.

(Synthesis Example 1)
In this synthesis example, compound 1 was synthesized according to the following scheme.

Under an argon atmosphere, 1.9 g (4.0 mmol) of compound 101 and 234 mg (0.32 mmol) of Pd (dppf) Cl ₂ were added to the reaction vessel, 48 ml of benzene, 24 ml of 2 mol / L potassium carbonate, tetrahydrofuran 12 ml of (THF) and 0.87 g (3 mmol) of Compound 102 were added and stirred at 75 ° C. for 72 hours. After stirring, an aqueous ammonium chloride solution was added to the reaction system to stop the reaction. Extraction was performed with toluene, and the organic layer was washed with brine, dried over magnesium sulfate, and concentrated. The resulting crude product was purified by column chromatography using hexane / chloroform as a solvent to obtain 960 mg of the target compound 103 (yield 50%).
NMR (in CDCl ₃ ): δ8.17-8.07 (m, 4H), 7.79 (d, J = 8.0, 1H), 7.68 (d, J = 8.5, 1H), 7.52-7.44 (m, 4H), 7.35 -7.32 (m, 4H), 7.26-7.20 (m, 2H), 7.10-7.03 (m, 6H), 6.98 (d, J = 8.5, 2H), 6.87 (s, 1H), 6.81 (s, 1H) , 6.71 (dd, J = 8.0, 7.5, 2H).

Under an argon atmosphere, 958 mg (1.5 mmol) of Compound 103 and 20 ml of tetrahydrofuran (THF) were placed in a reaction vessel and cooled to −78 ° C. 2 ml (3.2 mmol) of n-butyllithium was dropped into the reaction system and stirred for 3 hours. Then, 448 μl (2.5 mmol) of chlorodiphenylphosphine was added, stirred for 1 hour, returned to room temperature, and stirred overnight. . After completion of the reaction, water was added to stop the reaction, and the mixture was extracted with ethyl acetate and then concentrated. The obtained crude product was used in the next reaction without purification.
To the obtained product, 30 ml of methylene chloride and 9 ml of hydrogen peroxide were added and stirred overnight at room temperature. Thereafter, water was added to the reaction system to stop the reaction. After extraction with methylene chloride, the organic layer was washed with an aqueous sodium disulfite solution, and the organic layer was dried over magnesium sulfate and concentrated. Purification was performed by column chromatography using hexane / ethyl acetate as a solvent to obtain 550 mg of the target compound 1 (yield 48%).
NMR (in CDCl ₃ ): δ8.18 (d, J = 7.5, 1H), 8.12 (d, J = 7.5, 1H), 8.08 (d, J = 10.5, 1H), 8.04 (d, J = 7.5, 1H), 7.70 (d, J = 8.0, 1H), 7.57-7.42 (m, 3H), 7.37 (d, J = 8.5, 2H), 7.30-7.27 (m, 3H), 7.23 (t, J = 7.5 , 1H), 7.14 (t, J = 7.5, 1H), 7.05-6.98 (m, 7H), 6.93 (d, J = 8.5, 2H), 6.81 (s, 1H), 6.72 (d, J = 8.0, 6H), 6.64-6.63 (d, J = 8.0, 1H).

(Synthesis Examples 2-56 and 58-88)
Compounds 2-56 and 58-88 can be synthesized in the same manner as in Synthesis Example 1 and Synthesis Example 57 below.

(Synthesis Example 57)
In this synthesis example, compound 57 was synthesized according to the following scheme.

2,7-dibromo-2 ′, 7′-dicyano-9,9′-spirobifluorene 0.52 g (0.99 mmol, compound a), (2,3,6,7-tetrahydro-1H, 5H-benzo [Ij] 0.62 g (2.9 mmol) of quinolizin-9-yl) boronic acid was placed in a 100 mL three-necked flask, and 10 mL of toluene, 2 mL of ethanol, and 3 mL of 2M aqueous potassium carbonate solution were added to this mixture. This mixture was bubbled with nitrogen for 20 minutes. After bubbling, 0.090 g (0.078 mmol) of tetrakis (triphenylphosphine) palladium (0) was added to the mixture. This mixture was stirred at 70 ° C. for 21 hours under a nitrogen stream. After stirring, this mixture was added to 200 mL of toluene and 200 mL of water and stirred. After stirring, the organic layer and the aqueous layer were separated, and the organic layer was washed with saturated brine. After washing, magnesium sulfate was added to the organic layer and dried. After drying, the mixture was suction filtered to obtain a filtrate. The solid obtained by concentrating the obtained filtrate was washed with methanol. After washing, this solid was dissolved in chloroform and then re-precipitated by adding hexane to obtain a solid. The obtained solid was purified by silica gel column chromatography (developing solvent: chloroform). After purification, the obtained fraction was concentrated and the solid was recovered. As a result, a yellow powdered solid (compound 57) was obtained in a yield of 0.23 g and a yield of 33%.
¹ H NMR (500MHz, CDCl ₃ ): 7.98 (d, J = 8.0Hz, 2H), 7.83 (d, J = 8.0Hz, 2H), 7.71 (d, J = 8.0Hz, 2H), 7.57 (d, J = 8.0Hz, 2H), 7.14 (s, 2H), 6.84 (s, 4H), 6.67 (s, 2H), 3.12 (d, J = 11Hz, 8H), 2.72 (t, J = 6.4Hz, 8H ), 1.93 (d, J = 11Hz, 8H).
MS (MALDI): m / z calcd: 708.33 [M + H] ⁺ ; found: 708.29.

(Example 1)
In this production example, an organic electroluminescence device having a structure shown in FIG. 1 and a neat thin film were prepared using Compound 1, and the luminous efficiency was evaluated.
(1) Production and evaluation of organic electroluminescence device Indium tin oxide (ITO) 2 is formed on glass 1 with a thickness of about 30 to 100 nm, and further, compound 1 is vacuum-deposited thereon to form 80 nm. The film was formed with a thickness of. The mean square roughness (RMS) of the film forming surface was 1.34 nm. Next, lithium fluoride (LiF) 4 was vacuum-deposited by 0.7 nm, and then aluminum (Al) 5 was vapor-deposited to a thickness of 90 nm to obtain an organic electroluminescence device having the layer structure shown in FIG.
The result of having measured the current density-voltage-luminance (JVL) characteristic of the manufactured organic electroluminescent element using the semiconductor parameter analyzer and the power meter is shown in FIG. The element of this example achieved 1550 mA / cm ² at a driving voltage of 15.0 V and achieved 850 cd / m ² at a driving voltage of 13.0 V. Moreover, the result of having measured the current density-external quantum efficiency characteristic is shown in FIG. The device of this example achieved an external quantum efficiency of 0.47%.

(2) Production and evaluation of neat thin film A neat thin film was produced by depositing Compound 1 on a quartz substrate, and an emission spectrum was measured. The results are shown in FIG. Sharp emission having a peak at 432 nm was observed, and the emission quantum yield was 57%. Moreover, the energy level of HOMO was measured for the neat thin film of Compound 1 using a photoelectron spectrometer. Moreover, absorption edge energy was measured using the spectrophotometer, and this was prescribed | regulated as the energy gap. The position higher than the energy level of HOMO by the measured energy gap was defined as the energy level of LUMO. As a result, the energy level of HOMO was measured to be 5.3 eV, and the energy level of LUMO was measured to be 2.3 eV. FIG. 5 shows an energy level diagram of the organic electroluminescence element of this example.
From the above, it has been confirmed that Compound 1 has a good thin film forming ability and shows a high emission quantum yield in a neat thin film, and is suitable for the production of a single layer type organic electroluminescence device. It was.

(Examples 2-50, 52-57 and 59-88)
In the same manner as in Example 1, the usefulness of compounds 2 to 50, 52 to 57, and 59 to 88 can be confirmed.

(Example 51)
In this example, a toluene solution of compound 51 was prepared and the emission spectrum was measured (FIG. 6). When PL transient attenuation was measured at 300 K using a streak camera, a short-life component of 11.55 ns and a long-life component of 124.9 μs were observed (FIG. 7). That is, by the compound 51, in addition to the short-lived fluorescence, thermally activated delayed fluorescence derived from the long-lived component was observed.

(Example 57)
Using the compound 57 synthesized in Synthesis Example 57, the emission spectrum of the solution was measured in the same manner as in Example 51. As a result, light emission having a peak at 550 nm was observed. Further, when PL transient attenuation was measured, a short-life component of 10.61 ns and a long-life component of 434.38 μs were observed (FIG. 8). That is, by the compound 10, in addition to the short-lived fluorescence, thermally activated delayed fluorescence derived from the long-lived component was observed.

  The compound of the present invention is a compound useful as a light-emitting material for an organic electroluminescence device. In particular, neat thin films exhibit high emission quantum yields and high thin film forming ability, and thus are expected to be industrially applied to various organic electroluminescent devices such as single-layer organic electroluminescent devices. For this reason, this invention has high industrial applicability.

1 Glass 2 ITO
3 Compound 1
4 LiF
5 Al

［一般式（Ａ）において、Ｚ^１は窒素原子、酸素原子、硫黄原子または珪素原子を表し、Ａ^１およびＡ^２として各々独立に芳香環、ヘテロ芳香環、脂肪環または非芳香族ヘテロ環を形成していてもよい。一般式（Ｂ）において、Ｒ^２０は水素原子、アリール基またはＡ^４で表される環構造を形成するのに必要な原子群を表し、Ａ^３およびＡ^４として各々独立に、ヘテロ芳香環または非芳香族ヘテロ環を形成していてもよい。一般式（Ｃ）において、Ｚ^２、Ｚ^３、Ｚ^４およびＺ^５は各々独立に酸素原子または硫黄原子を表す。］
［６］ 一般式（１）のＲ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５、Ｒ^６、Ｒ^７およびＲ^８の少なくとも１つが、下記Ｄ１〜Ｄ１３のいずれかの構造を有することを特徴とする［１］に記載の有機エレクトロルミネッセンス素子。[0006]
[Chemical formula 4]

[In General Formula (A), Z ¹ represents a nitrogen atom, an oxygen atom, a sulfur atom or a silicon atom, and each of A ¹ and A ² independently represents an aromatic ring, a heteroaromatic ring, an aliphatic ring or a non-aromatic heterocyclic ring. It may be formed. In the general formula (B), R ²⁰ represents an atomic group necessary to form a ring structure represented by a hydrogen atom, an aryl group, or A ^4, each independently as A ³ and A ^4, heteroaromatic ring, or A non-aromatic heterocycle may be formed. In the general formula (C), Z ² , Z ³ , Z ⁴ and Z ⁵ each independently represent an oxygen atom or a sulfur atom. ]
[6] At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) has any one of the following structures D1 to D13. The organic electroluminescence device according to [1], which is characterized in that

[0021]
Ring, isoquinoline ring, cinnoline ring, quinazoline ring, quinoxaline ring, phthalazine ring, pteridine ring, xanthene ring, carbazole ring, phenanthridine ring, acridine ring, phenazine ring, phenanthroline ring and the like.
[0024]
In the general formula (B), R ²⁰ represents a hydrogen atom, an aryl group, or an atomic group necessary for forming a ring structure represented by A ⁴ . In addition, A ³ and A ⁴ in the general formula (B) may each independently form a heteroaromatic ring or a non-aromatic heterocycle, or may not form these rings. For specific examples of the heteroaromatic ring or non-aromatic heterocycle that A ³ and A ⁴ can form, see the specific examples of the heteroaromatic ring or non-aromatic heterocycle that A ¹ and A ² can form above. be able to. In addition, the aryl group that R ²⁰ can take may be a single aromatic ring or a structure in which two or more aromatic rings are fused. The number of carbon atoms constituting the aryl group is preferably 6-22, more preferably 6-18, further preferably 6-14, and 6-10 (that is, benzene ring, naphthalene). Ring) is even more preferred, and a phenyl group is most preferred.
[0025]
As an example of the structure represented by the general formula (B), for example, when R ²⁰ is a hydrogen atom and A ³ does not form a ring structure, the general formula (B) represents an aniline skeleton. When R ²⁰ is a benzene ring and A ³ does not form a ring structure, the general formula (B) represents a diphenylamine skeleton. Further, when R ²⁰ is an atomic group necessary for forming a piperidine ring and A ³ forms a piperidine ring, the general formula (B) represents a julolidine skeleton.
[0026]
In the general formula (C), Z ² , Z ³ , Z ⁴ and Z ⁵ each independently represent an oxygen atom or a sulfur atom. These atoms may be the same or different, but are preferred when they are the same.
[0027]
Preferred specific examples of the electron donating group represented by at least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are listed below. However, the electron donating groups that can be employed in the general formula (1) are limited by these specific examples.

Claims (18)

An organic electroluminescence device having an anode, a cathode, and at least one organic layer including a light emitting layer between the anode and the cathode, wherein the light emitting layer is represented by the following general formula (1). An organic electroluminescence device comprising a fluorene compound.

[In General Formula (1), R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are each independently a hydrogen atom or an electron-donating group, and at least one of Represents an electron donating group. R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ are each independently an electron withdrawing group other than a hydrogen atom or a triazino group, at least one of which is other than a triazino group Represents an electron withdrawing group. ^However, the ^{R 1, R 2, R 3} , R 4, R 5, R 6, R 7, R 8, R 9, R 10, R 11, R 12, R 13, R 14, R 15 and ^{R 16} 11-14 of them are hydrogen atoms. ] At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) is an aryl group substituted with an electron donating group The organic electroluminescent element according to claim 1. At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) has a structure represented by the following general formula (2) The organic electroluminescent element according to claim 1.

[In General Formula (2), R ²¹ , R ²² , R ²³ , R ²⁴ and R ²⁵ are each independently a hydrogen atom or an electron-donating group, and at least one represents an electron-donating group. ] At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) is represented by any one of the following general formulas (3) to (5). The organic electroluminescence device according to claim 1, wherein the organic electroluminescence device has a structure.

[In the above formula, R ³¹ and R ³² each independently represent a substituted or unsubstituted aryl group, and the aryl group represented by R ³¹ and the aryl group represented by R ³² may be linked. R ⁴¹ , R ⁴² and R ⁴³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁴¹ and R ⁴² together form a ring structure. R ⁴² and R ⁴³ may together form a ring structure. R ⁵¹ , R ⁵² and R ⁵³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁵¹ and R ⁵² together form a ring structure. R ⁵² and R ⁵³ may be combined to form a ring structure. ] At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) is represented by any one of the following general formulas (A) to (C). The organic electroluminescence device according to claim 1, wherein the organic electroluminescence device has a structure.

[In General Formula (A), Z ¹ represents a nitrogen atom, an oxygen atom, a sulfur atom or a silicon atom, and each of A ¹ and A ² independently represents an aromatic ring, a heteroaromatic ring, an aliphatic ring or a non-aromatic heterocyclic ring. It may be formed. In the general formula (B), R ²⁰ represents an atomic group necessary to form a ring structure represented by a hydrogen atom, an aryl group, or A ^4, each independently as A ³ and A ^4, heteroaromatic ring, or A non-aromatic heterocycle may be formed. In the general formula (C), Z ¹ , Z ² , Z ³ and Z ⁴ each independently represent an oxygen atom or a sulfur atom. ] At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) has any one of the following structures D1 to D13 The organic electroluminescent element according to claim 1.

At least one of R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ^{16 in} the general formula (1) is represented by any one of the following general formulas (6) to (9). The organic electroluminescence device according to claim 1, wherein the organic electroluminescence device has a structure.

[In the above formula, R ⁶¹ and R ⁶² each independently represents a substituted or unsubstituted aryl group. R ⁷¹ and R ⁷² each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁷¹ and R ⁷² may form a ring structure together. Good. R ⁸¹ , R ⁸² and R ⁸³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁸¹ and R ⁸² together form a ring structure. R ⁸² and R ⁸³ may be combined to form a ring structure. R ⁹¹ represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and Z represents a linking group necessary for forming a heteroaromatic ring other than a triazine ring. ] 2. At least one of R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ^{16 in} the general formula (1) has one of the following structures: The organic electroluminescent element as described in any one of -6.

  It has a light emitting layer which consists only of a compound represented by the said General formula (1), The organic electroluminescent element as described in any one of Claims 1-8 characterized by the above-mentioned.   The organic electroluminescence device according to claim 1, wherein the compound represented by the general formula (1) is used as a dopant of a light emitting layer.   It has only a light emitting layer as an organic layer, The organic electroluminescent element as described in any one of Claims 1-10 characterized by the above-mentioned. A monospirobifluorene compound represented by the following general formula (1 ′).

[In the general formula (1 ′), R ^{1 ′} , R ^{2 ′} , R ^{3 ′} , R ^{4 ′} , R ^{5 ′} , R ^{6 ′} , R ^{7 ′} and R ^{8 ′} are each independently a hydrogen atom or an electron donor. A group, at least one of which represents an aryl group substituted with an electron donating group. R ^{9 ′} , R ^{10 ′} , R ^{11 ′} , R ^{12 ′} , R ^{13 ′} , R ^{14 ′} , R ^{15 ′} and R ^{16 ′} are each independently an electron withdrawing group other than a hydrogen atom or a triazino group, At least one represents an electron withdrawing group other than the triazino group. However, R ^{1 ′} , R ^{2 ′} , R ^{3 ′} , R ^{4 ′} , R ^{5 ′} , R ^{6 ′} , R ^{7 ′} , R ^{8 ′} , R ^{9 ′} , R ^{10 ′} , R ^{11 ′} , R ^{12 ′} , 11 to ^{14 of} R ^{13 ′} , R ^{14 ′} , R ^{15 ′} and R ^{16 ′} are hydrogen atoms. ] At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) has a structure represented by the following general formula (2) The compound according to claim 12.

[In General Formula (2), R ²¹ , R ²² , R ²³ , R ²⁴ and R ²⁵ are each independently a hydrogen atom or an electron-donating group, and at least one represents an electron-donating group. ] At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) is represented by any one of the following general formulas (3) to (5). The compound according to claim 12, which has the following structure:

[In the above formula, R ³¹ and R ³² each independently represent a substituted or unsubstituted aryl group, and the aryl group represented by R ³¹ and the aryl group represented by R ³² may be linked. R ⁴¹ , R ⁴² and R ⁴³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁴¹ and R ⁴² together form a ring structure. R ⁴² and R ⁴³ may together form a ring structure. R ⁵¹ , R ⁵² and R ⁵³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁵¹ and R ⁵² together form a ring structure. R ⁵² and R ⁵³ may be combined to form a ring structure. ] 13. At least one of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 in} the general formula (1) has one of the following structures: Compound described in 1.

At least one of R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ^{16 in} the general formula (1) is represented by any one of the following general formulas (6) to (9). The compound according to any one of claims 12 to 15, which has the following structure.

[In the above formula, R ⁶¹ and R ⁶² each independently represents a substituted or unsubstituted aryl group. R ⁷¹ and R ⁷² each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁷¹ and R ⁷² may form a ring structure together. Good. R ⁸¹ , R ⁸² and R ⁸³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R ⁸¹ and R ⁸² together form a ring structure. R ⁸² and R ⁸³ may be combined to form a ring structure. R ⁹¹ represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and Z represents a linking group necessary for forming a heteroaromatic ring other than a triazine ring. ] ^{13. At} least one of R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ^{16 in} the general formula (1) has one of the following structures: The compound as described in any one of -16.

  The luminescent material which consists of a compound as described in any one of Claims 12-17.

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