JP2011178742A - Compound having phenoxazine ring structure or phenothiazine ring structure and organic electroluminescent element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic compound having excellent hole injection and transportation property, electron stopping power, high stability in a state of a thin film and excellent heat-resistance and useful as a material for an organic electroluminescent element having high efficiency and high durability and to provide the organic electroluminescent element having high efficiency and high durability by using the compound. <P>SOLUTION: There are provided the compound having a substituted phenoxazine ring structure or phenothiazine ring structure and expressed by general formula (1), and the organic electroluminescent element having a pair of electrodes and at least one organic layer sandwiched between the electrodes, wherein the compound is used as a constitution material of at least one organic layer. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a compound suitable for an organic electroluminescence element which is a self-luminous element suitable for various display devices and the element, and more specifically, a compound having a phenoxazine ring structure or a phenothiazine ring structure, and the compound The present invention relates to an organic electroluminescence device using the above.

  Since organic electroluminescent elements are self-luminous elements, they have been actively researched because they are brighter and more visible than liquid crystal elements and can display clearly.

In 1987, Eastman Kodak's C.I. W. Tang et al. Have made organic electroluminescence elements using organic materials practical by developing a laminated structure element that shares various roles with each material. They are composed of a phosphor that can transport electrons, tris (8-hydroxyquinoline) aluminum (hereinafter abbreviated as Alq ₃ ) and an aromatic amine compound that can transport holes, Was injected into the phosphor layer to emit light, whereby high luminance of 1000 cd / m ² or more was obtained at a voltage of 10 V or less (see, for example, Patent Document 1 and Patent Document 2).

  To date, many improvements have been made for the practical application of organic electroluminescence devices, and various roles have been further subdivided, and sequentially on the substrate, anode, hole injection layer, hole transport layer, light emitting layer, electron High efficiency and durability are achieved by an electroluminescent device provided with a transport layer, an electron injection layer, and a cathode (see, for example, Non-Patent Document 1).

  Further, the use of triplet excitons has been attempted for the purpose of further improving the luminous efficiency, and the use of phosphorescent emitters has been studied (for example, see Non-Patent Document 2).

The light-emitting layer can also be produced by doping a charge transporting compound generally called a host material with a phosphor or a phosphorescent material. As described in the above seminar proceedings collection, the selection of an organic material in an organic electroluminescence element greatly affects various characteristics such as efficiency and durability of the element.

In an organic electroluminescence device, the light injected from both electrodes recombines in the light emitting layer to obtain light emission. However, it is important how efficiently both holes and electrons are transferred to the light emitting layer. Improve the probability of recombination of holes and electrons by increasing the hole injection property and blocking the electron injected from the cathode, and further confine excitons generated in the light emitting layer Thus, high luminous efficiency can be obtained. Therefore, the role of the hole transport material is important, and there is a demand for a hole transport material that has high hole injectability, high hole mobility, high electron blocking properties, and high durability against electrons. ing.

In addition, the heat resistance and amorphousness of the material are also important for the lifetime of the element. In a material having low heat resistance, thermal decomposition occurs even at a low temperature due to heat generated when the element is driven, and the material is deteriorated. In the case of a material having low amorphous property, the thin film is crystallized even in a short time, and the element is deteriorated. For this reason, the material used is required to have high heat resistance and good amorphous properties.

Examples of hole transport materials that have been used in organic electroluminescence devices so far include N, N′-diphenyl-N, N′-di (α-naphthyl) benzidine (hereinafter abbreviated as NPD) and various aromatics. Amine derivatives have been known (see, for example, Patent Document 1 and Patent Document 2). NPD has a good hole transport capability, but its glass transition point (Tg), which is an index of heat resistance, is as low as 96 ° C., and device characteristics are degraded due to crystallization under high temperature conditions (for example, Non-Patent Document 3). Further, among the aromatic amine derivatives described in Patent Document 1 and Patent Document 2, compounds having excellent mobility such as hole mobility of 10 ⁻³ cm ² / Vs or more are known. In addition, since the electron blocking property is insufficient, a part of the electrons pass through the light emitting layer, and the improvement of the light emission efficiency cannot be expected. There has been a demand for materials that are stable and have high heat resistance.

As compounds having improved characteristics such as heat resistance and hole injection properties, arylamine compounds having a substituted phenoxazine structure and a substituted phenothiazine structure represented by the following formulas (for example, compounds A to C) have been proposed. (For example, refer to Patent Documents 3 to 6).

However, devices using these compounds in the hole injection layer or hole transport layer have been improved in heat resistance and light emission efficiency, but are still not sufficient. The efficiency was not sufficient, and there was a problem with amorphousness. For this reason, there has been a demand for lower drive voltage and higher light emission efficiency while improving amorphousness.

JP-A-8-048656 Japanese Patent No. 3194657 JP 2009-029807 A JP 7-138562 A JP-A-8-269445 JP-A-9-310066

Proceedings of the 9th meeting of the Japan Society of Applied Physics 55-61 pages (2001) Proceedings of the 9th Workshop of the Japan Society of Applied Physics 23-31 pages (2001) Proceedings of the 3rd Regular Meeting of the Organic EL Discussion Group, 13-14 pages (2006) J. et al. Org. Chem. , 49, 1905 (1984) J. et al. Org. Chem. , 60, 7508 (1995) Synth. Commun. , 11, 513 (1981)

The object of the present invention is as a highly efficient and durable organic electroluminescent device material, excellent in hole injection / transport performance, electron blocking ability, high stability in a thin film state, and heat resistance It is another object of the present invention to provide an organic compound having excellent characteristics and to provide an organic electroluminescence device having high efficiency and high durability by using this compound.

The physical characteristics of the organic compound to be provided by the present invention are as follows: (1) good hole injection characteristics; (2) high hole mobility; and (3) electron blocking ability. (4) The thin film state is stable, and (5) The heat resistance is excellent. The physical characteristics of the organic electroluminescent device to be provided by the present invention include (1) high luminous efficiency and power efficiency, (2) low emission start voltage, and (3) practical use. The drive voltage is low.

  Therefore, in order to achieve the above-mentioned object, the present inventors have confirmed that the aromatic tertiary amine structure has a high hole injection / transport capability and that the phenoxazine ring structure and the phenothiazine ring structure have electron blocking properties. In addition, the compound having a phenoxazine ring structure or a phenothiazine ring structure is designed and chemically synthesized in anticipation of the effects on the heat resistance and thin film stability of these partial structures. As a result of prototyping various organic electroluminescence elements using the above and intensively evaluating the characteristics of the elements, the present invention has been completed.

That is, the present invention is a compound having a substituted phenoxazine ring structure or phenothiazine ring structure represented by the following general formula (1).

（１）

(1)

Wherein X is an oxygen atom or a sulfur atom, and A is a substituted or unsubstituted aromatic hydrocarbon, a substituted or unsubstituted aromatic heterocyclic ring or a substituted or unsubstituted condensed polycyclic aromatic divalent group. Ar 1, Ar 2, Ar 3 may be the same or different from each other, and are substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic heterocyclic groups, or substituted or unsubstituted condensed polycyclic aromatics Here, Ar2 and Ar3 may be directly bonded to each other via a single bond or a substituted or unsubstituted methylene group to form a ring, and the substituents of Ar2 and Ar3 may be a single bond, substituted or A ring may be bonded to each other via an unsubstituted methylene group, an oxygen atom or a sulfur atom, and R1 to R7 may be the same as or different from each other, and may be a hydrogen atom, a deuterium atom or a fluorine atom. A chlorine atom, a cyano group, a trifluoromethyl group, a nitro group, an optionally substituted linear or branched alkyl group having 1 to 6 carbon atoms, and an optionally substituted carbon A cycloalkyl group having 5 to 10 atoms, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent, and 1 to 1 carbon atoms which may have a substituent. 6 linear or branched alkyloxy groups, optionally substituted cycloalkyloxy groups having 5 to 10 carbon atoms, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted An aromatic heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group, or a substituted or unsubstituted aryloxy group, which has a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom; It may be bonded to each other to form a ring with.)

Moreover, this invention is a compound which has the substituted phenoxazine ring structure or phenothiazine ring structure represented by following General formula (2).

Wherein X is an oxygen atom or a sulfur atom, and A is a substituted or unsubstituted aromatic hydrocarbon, a substituted or unsubstituted aromatic heterocyclic ring or a substituted or unsubstituted condensed polycyclic aromatic divalent group. Ar 1, Ar 2, Ar 3 may be the same or different from each other, and are substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic heterocyclic groups, or substituted or unsubstituted condensed polycyclic aromatics Here, Ar2 and Ar3 may be directly bonded to each other via a single bond or a substituted or unsubstituted methylene group to form a ring, and the substituents of Ar2 and Ar3 may be a single bond, substituted or A ring may be bonded to each other via an unsubstituted methylene group, an oxygen atom or a sulfur atom, and R1 to R7 may be the same as or different from each other, and may be a hydrogen atom, a deuterium atom or a fluorine atom. A chlorine atom, a cyano group, a trifluoromethyl group, a nitro group, an optionally substituted linear or branched alkyl group having 1 to 6 carbon atoms, and an optionally substituted carbon A cycloalkyl group having 5 to 10 atoms, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent, and 1 to 1 carbon atoms which may have a substituent. 6 linear or branched alkyloxy groups, optionally substituted cycloalkyloxy groups having 5 to 10 carbon atoms, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted Aromatic heterocyclic group, substituted or unsubstituted condensed polycyclic aromatic group or substituted or unsubstituted aryloxy group, wherein R1 and R2, R2 and R3, R3 and R4, R6 and R7 are single bonds, substituted if Unsubstituted methylene group, via an oxygen atom or a sulfur atom may be bonded to each other to form a ring.)

Moreover, this invention is a compound which has the substituted phenoxazine ring structure or phenothiazine ring structure represented by following General formula (3).

(In the formula, X is an oxygen atom or a sulfur atom, and Ar1, Ar2, and Ar3 may be the same or different from each other, and are substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic heterocyclic groups. Or a substituted or unsubstituted condensed polycyclic aromatic group, wherein Ar2 and Ar3 may be directly bonded to each other via a single bond or a substituted or unsubstituted methylene group to form a ring; , Ar3 substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom, and R1 to R11 may be the same or different from each other; A straight or branched alkyl group having 1 to 6 carbon atoms which may have a hydrogen atom, deuterium atom, fluorine atom, chlorine atom, cyano group, trifluoromethyl group, nitro group or substituent. A cycloalkyl group having 5 to 10 carbon atoms which may have a substituent, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent, a substituent A linear or branched alkyloxy group having 1 to 6 carbon atoms which may have a group, a cycloalkyloxy group having 5 to 10 carbon atoms which may have a substituent, substituted or unsubstituted A substituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group, or a substituted or unsubstituted aryloxy group, R1 and R2, R2 and R3 R3 and R4, R6 and R7, R8 and R9, R10 and R11 may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom.

Moreover, this invention is a compound which has the substituted phenoxazine ring structure or phenothiazine ring structure represented by following General formula (4).

Wherein X is an oxygen atom or a sulfur atom, and A is a substituted or unsubstituted aromatic hydrocarbon, a substituted or unsubstituted aromatic heterocyclic ring or a substituted or unsubstituted condensed polycyclic aromatic divalent group. Ar2 and Ar3 may be the same or different from each other, and represent a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted condensed polycyclic aromatic group. Here, Ar2 and Ar3 may be directly bonded to each other through a single bond or a substituted or unsubstituted methylene group to form a ring, and the substituents of Ar2 and Ar3 are a single bond, substituted or unsubstituted. R1 to R7 and R12 to R16 may be the same as or different from each other through a methylene group, an oxygen atom or a sulfur atom, and may be a hydrogen atom, a deuterium atom, a fluorine atom. A linear or branched alkyl group having 1 to 6 carbon atoms which may have a primary atom, a chlorine atom, a cyano group, a trifluoromethyl group, a nitro group, or a substituent; A cycloalkyl group having 5 to 10 carbon atoms, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent, and a carbon atom which may have a substituent A linear or branched alkyloxy group having 1 to 6 carbon atoms, an optionally substituted cycloalkyloxy group having 5 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group, substituted or An unsubstituted aromatic heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group or a substituted or unsubstituted aryloxy group, R1 and R2, R2 and R3, R3 and R4, R6 and R7, R12 When 13, R13 and R14, R14 and R15, R15 and R16 is a single bond, a substituted or unsubstituted methylene group, linked to each other through an oxygen atom or a sulfur atom may form a ring.)

In addition, the present invention provides an organic electroluminescence device having a pair of electrodes and at least one organic layer sandwiched between the electrodes. The general formula (1), the general formula (2), the general formula (3), or the general formula (4) A compound having a substituted phenoxazine ring structure or a phenothiazine ring structure represented by formula (1) is used as a constituent material of at least one organic layer.

  “A linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent” represented by R1 to R16 in the general formulas (1) to (4), “substituent “The number of carbon atoms” in the “cycloalkyl group having 5 to 10 carbon atoms” which may have or “the linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent” Examples of “a linear or branched alkyl group having 1 to 6”, “cycloalkyl group having 5 to 10 carbon atoms” or “linear or branched alkenyl group having 2 to 6 carbon atoms” include And methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, n-hexyl group, cyclopentyl group. Cyclohexyl, 1-adamantyl, 2-adamantyl, vinyl, allyl, and the like isopropenyl and 2-butenyl groups. These groups may be bonded to each other through a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom to form a ring.

  “A linear or branched alkyl group having 1 to 6 carbon atoms having a substituent” represented by R1 to R16 in the general formulas (1) to (4), “5 carbon atoms having a substituent” Specific examples of the “substituent” in “to 10 cycloalkyl group” or “straight-chain or branched alkenyl group having 2 to 6 carbon atoms having a substituent” include deuterium atom, trifluoromethyl group , Cyano group, nitro group; halogen atom such as fluorine atom, chlorine atom, bromine atom, iodine atom; linear or branched alkoxy group having 1 to 6 carbon atoms such as methoxy group, ethoxy group, propyloxy group Alkenyl groups such as allyl groups; aryloxy groups such as phenoxy groups and tolyloxy groups; arylalkoxy groups such as benzyloxy groups and phenethyloxy groups; Group, biphenylyl group, terphenylyl group, naphthyl group, anthracenyl group, phenanthryl group, fluorenyl group, indenyl group, pyrenyl group, perylenyl group, fluoranthenyl group, triphenylenyl group and other aromatic hydrocarbon groups or condensed polycyclic aromatic groups ; Pyridyl group, furanyl group, pyranyl group, thienyl group, furyl group, pyrrolyl group, thiophenyl group, quinolyl group, isoquinolyl group, benzofuranyl group, benzothiophenyl group, indolyl group, carbazolyl group, benzoxazolyl group, benzothiazolyl group , Quinoxalyl group, benzimidazolyl group, pyrazolyl group, dibenzofuranyl group, dibenzothiophenyl group, carbolinyl group and other groups such as aromatic heterocyclic groups, and these substituents may be further substituted with other substituents. Replaced by It may have. These substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom to form a ring.

"A linear or branched alkyloxy group having 1 to 6 carbon atoms which may have a substituent" represented by R1 to R16 in the general formulas (1) to (4) or "substituents" A “linear or branched alkyloxy group having 1 to 6 carbon atoms” or “cycloalkyl having 5 to 10 carbon atoms” in the “cycloalkyloxy group having 5 to 10 carbon atoms” which may have As the “oxy group”, specifically, methyloxy group, ethyloxy group, n-propyloxy group, isopropyloxy group, n-butyloxy group, tert-butyloxy group, n-pentyloxy group, n-hexyloxy group, cyclopentyl Oxy group, cyclohexyloxy group, cycloheptyloxy group, cyclooctyloxy group, 1-adamantyloxy group and 2-adaman Or the like can be mentioned aryloxy group. These groups may be bonded to each other through a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom to form a ring.

  “A linear or branched alkyloxy group having 1 to 6 carbon atoms having a substituent” represented by R1 to R16 in the general formulas (1) to (4) or “the number of carbon atoms having a substituent” Specific examples of the “substituent” in “5 to 10 cycloalkyloxy groups” include deuterium atom, trifluoromethyl group, cyano group, nitro group; halogen such as fluorine atom, chlorine atom, bromine atom and iodine atom. Atom: linear or branched alkoxy group having 1 to 6 carbon atoms such as methoxy group, ethoxy group and propyloxy group; alkenyl group such as allyl group; aryloxy group such as phenoxy group and tolyloxy group; benzyloxy Group, arylalkoxy group such as phenethyloxy group; phenyl group, biphenylyl group, terphenylyl group, naphthyl group, anthraceni Group, phenanthryl group, fluorenyl group, indenyl group, pyrenyl group, perylenyl group, fluoranthenyl group, triphenylenyl group and other aromatic hydrocarbon groups or condensed polycyclic aromatic groups; pyridyl group, furanyl group, pyranyl group, thienyl group , Furyl group, pyrrolyl group, thiophenyl group, quinolyl group, isoquinolyl group, benzofuranyl group, benzothiophenyl group, indolyl group, carbazolyl group, benzoxazolyl group, benzothiazolyl group, quinoxalyl group, benzimidazolyl group, pyrazolyl group, dibenzofuran A group such as an aromatic heterocyclic group such as a nyl group, a dibenzothiophenyl group, and a carbolinyl group can be exemplified, and these substituents may be further substituted with other substituents. These substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom to form a ring.

  "Substituted or unsubstituted aromatic hydrocarbon group", "substituted or unsubstituted aromatic heterocyclic group" represented by R1 to R16 in the general formulas (1) to (4) or "substituted or unsubstituted As the “aromatic hydrocarbon group”, “aromatic heterocyclic group” or “fused polycyclic aromatic group” in the “fused polycyclic aromatic group”, specifically, phenyl group, biphenylyl group, terphenylyl group, naphthyl group , Anthryl group, phenanthryl group, fluorenyl group, indenyl group, pyrenyl group, perylenyl group, fluoranthenyl group, triphenylenyl group, pyridyl group, furanyl group, pyranyl group, thiophenyl group, quinolyl group, isoquinolyl group, benzofuranyl group, benzothiol Phenyl, indolyl, carbazolyl, benzoxazolyl, benzothiazolyl, quinoxalyl, benzo Imidazolyl group, a pyrazolyl group, a dibenzofuranyl group, and the like dibenzothiophenyl group and carbolinyl group. These groups may be bonded to each other through a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom to form a ring.

“Substituent” in “Substituted aromatic hydrocarbon group”, “Substituted aromatic heterocyclic group” or “Substituted condensed polycyclic aromatic group” represented by R1 to R16 in formulas (1) to (4) Specifically, deuterium atom, trifluoromethyl group, cyano group, nitro group; halogen atom such as fluorine atom, chlorine atom, bromine atom, iodine atom; methyl group, ethyl group, n-propyl group, isopropyl A linear or branched alkyl group having 1 to 6 carbon atoms such as a group, n-butyl group, isobutyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, n-hexyl group; A straight-chain or branched alkoxy group having 1 to 6 carbon atoms such as an alkenyl group, an ethoxy group or a propyloxy group; an alkenyl group such as an allyl group; a benzyl group, a naphthylmethyl group, Aralkyl groups such as netyl group; aryloxy groups such as phenoxy group and tolyloxy group; arylalkoxy groups such as benzyloxy group and phenethyloxy group; phenyl group, biphenylyl group, terphenylyl group, naphthyl group, anthracenyl group, phenanthryl group, fluorenyl group Group, indenyl group, pyrenyl group, perylenyl group, fluoranthenyl group, triphenylenyl group and other aromatic hydrocarbon groups or condensed polycyclic aromatic groups; pyridyl group, furanyl group, pyranyl group, thienyl group, furyl group, pyrrolyl group , Thiophenyl group, quinolyl group, isoquinolyl group, benzofuranyl group, benzothiophenyl group, indolyl group, carbazolyl group, benzoxazolyl group, benzothiazolyl group, quinoxalyl group, benzoimidazolyl group, pyrazolyl group, diben Aromatic heterocyclic groups such as furanyl group, dibenzothiophenyl group and carbolinyl group; aryl vinyl groups such as styryl group and naphthyl vinyl group; acyl groups such as acetyl group and benzoyl group; dialkylamino groups such as dimethylamino group and diethylamino group A disubstituted amino group substituted with an aromatic hydrocarbon group such as a diphenylamino group or a dinaphthylamino group or a condensed polycyclic aromatic group; a diaralkylamino group such as a dibenzylamino group or a diphenethylamino group; Disubstituted amino groups substituted with aromatic heterocyclic groups such as pyridylamino groups and dithienylamino groups; Dialkenylamino groups such as diallylamino groups; Alkyl groups, aromatic hydrocarbon groups, condensed polycyclic aromatic groups, aralkyls Disubstituted by a substituent selected from a group, aromatic heterocyclic group or alkenyl group Examples thereof include an amino group, and these substituents may be further substituted. These substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom to form a ring.

Specific examples of the “aryloxy group” in the “substituted or unsubstituted aryloxy group” represented by R1 to R16 in the general formulas (1) to (4) include a phenoxy group, a tolyloxy group, and biphenylyloxy. Group, terphenylyloxy group, naphthyloxy group, anthryloxy group, phenanthryloxy group, fluorenyloxy group, indenyloxy group, pyrenyloxy group, perylenyloxy group and the like. These groups may be bonded to each other through a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom to form a ring.

Specific examples of the “substituent” in the “substituted aryloxy group” represented by R1 to R16 in the general formulas (1) to (4) include a deuterium atom, a trifluoromethyl group, a cyano group, and a nitro group. Halogen atoms such as fluorine atom, chlorine atom, bromine atom, iodine atom; methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, n-pentyl group, isopentyl A linear or branched alkyl group having 1 to 6 carbon atoms such as a group, neopentyl group or n-hexyl group; a linear or branched alkyl group having 1 to 6 carbon atoms such as a methoxy group, an ethoxy group or a propyloxy group; Branched alkoxy groups; alkenyl groups such as allyl groups; aralkyl groups such as benzyl groups, naphthylmethyl groups, and phenethyl groups; phenoxy groups, tolyloxy groups Aryloxy groups such as groups; arylalkoxy groups such as benzyloxy groups and phenethyloxy groups; phenyl groups, biphenylyl groups, terphenylyl groups, naphthyl groups, anthracenyl groups, phenanthryl groups, fluorenyl groups, indenyl groups, pyrenyl groups, perylenyl groups, Aromatic hydrocarbon group or condensed polycyclic aromatic group such as fluoranthenyl group and triphenylenyl group; pyridyl group, furanyl group, pyranyl group, thienyl group, furyl group, pyrrolyl group, thiophenyl group, quinolyl group, isoquinolyl group, benzofuranyl group Group, benzothiophenyl group, indolyl group, carbazolyl group, benzoxazolyl group, benzothiazolyl group, quinoxalyl group, benzoimidazolyl group, pyrazolyl group, dibenzofuranyl group, dibenzothiophenyl group, carbolinyl group Aromatic heterocyclic groups; aryl vinyl groups such as styryl groups and naphthyl vinyl groups; acyl groups such as acetyl groups and benzoyl groups; dialkylamino groups such as dimethylamino groups and diethylamino groups; diphenylamino groups and dinaphthylamino groups A disubstituted amino group substituted with an aromatic hydrocarbon group or a condensed polycyclic aromatic group; a diaralkylamino group such as a dibenzylamino group or a diphenethylamino group; an aromatic such as a dipyridylamino group or a dithienylamino group A disubstituted amino group substituted by a heterocyclic group; a dialkenylamino group such as a diallylamino group; an alkyl group, an aromatic hydrocarbon group, a condensed polycyclic aromatic group, an aralkyl group, an aromatic heterocyclic group or an alkenyl group And a group such as a disubstituted amino group substituted with a selected substituent. Further, it may be substituted. These substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom to form a ring.

“Substituted or unsubstituted aromatic hydrocarbon group”, “substituted or unsubstituted aromatic heterocyclic group” represented by Ar1 to Ar3 in the general formulas (1) to (4), or “substituted or unsubstituted As the “aromatic hydrocarbon group”, “aromatic heterocyclic group” or “fused polycyclic aromatic group” in the “fused polycyclic aromatic group”, specifically, phenyl group, biphenylyl group, terphenylyl group, naphthyl group , Anthryl group, phenanthryl group, fluorenyl group, indenyl group, pyrenyl group, perylenyl group, fluoranthenyl group, triphenylenyl group, pyridyl group, furanyl group, pyranyl group, thiophenyl group, quinolyl group, isoquinolyl group, benzofuranyl group, benzothiol Phenyl group, indolyl group, carbazolyl group, benzoxazolyl group, benzothiazolyl group, quinoxalyl group, ben Imidazolyl group, a pyrazolyl group, and a dibenzofuranyl group, a dibenzothiophenyl group, and carbolinyl group and the like. In addition, these groups may be directly bonded to each other via a single bond or a substituted or unsubstituted methylene group to form a ring.
Here, as the “aromatic heterocyclic group” in the “substituted or unsubstituted aromatic heterocyclic group” represented by Ar 2 to Ar 3 in the general formulas (1) to (4), a thiophenyl group, benzothiophenyl Sulfur-containing aromatic heterocyclic groups such as a group, benzothiazolyl group and dibenzothiophenyl group are preferred.

“Substituent” in “Substituted aromatic hydrocarbon group”, “Substituted aromatic heterocyclic group” or “Substituted condensed polycyclic aromatic group” represented by Ar1 to Ar3 in formulas (1) to (4) Specifically, deuterium atom, trifluoromethyl group, cyano group, nitro group; halogen atom such as fluorine atom, chlorine atom, bromine atom, iodine atom; methyl group, ethyl group, n-propyl group, isopropyl A linear or branched alkyl group having 1 to 6 carbon atoms such as a group, n-butyl group, isobutyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, n-hexyl group; A linear or branched alkoxy group having 1 to 6 carbon atoms such as an alkenyl group; an alkenyl group such as an allyl group; a benzyl group, a naphthylmethyl group, Aralkyl groups such as ethenyl groups; aryloxy groups such as phenoxy groups and tolyloxy groups; arylalkoxy groups such as benzyloxy groups and phenethyloxy groups; phenyl groups, biphenylyl groups, terphenylyl groups, naphthyl groups, anthracenyl groups, phenanthryl groups, fluorenyl groups Group, indenyl group, pyrenyl group, perylenyl group, fluoranthenyl group, triphenylenyl group and other aromatic hydrocarbon groups or condensed polycyclic aromatic groups; pyridyl group, furanyl group, pyranyl group, thienyl group, furyl group, pyrrolyl group , Thiophenyl group, quinolyl group, isoquinolyl group, benzofuranyl group, benzothiophenyl group, indolyl group, carbazolyl group, benzoxazolyl group, benzothiazolyl group, quinoxalyl group, benzoimidazolyl group, pyrazolyl group, dibe Aromatic heterocyclic groups such as zofuranyl group, dibenzothiophenyl group and carbolinyl group; aryl vinyl groups such as styryl group and naphthyl vinyl group; acyl groups such as acetyl group and benzoyl group; dialkylamino groups such as dimethylamino group and diethylamino group A disubstituted amino group substituted with an aromatic hydrocarbon group such as a diphenylamino group or a dinaphthylamino group or a condensed polycyclic aromatic group; a diaralkylamino group such as a dibenzylamino group or a diphenethylamino group; Disubstituted amino groups substituted with aromatic heterocyclic groups such as pyridylamino groups and dithienylamino groups; Dialkenylamino groups such as diallylamino groups; Alkyl groups, aromatic hydrocarbon groups, condensed polycyclic aromatic groups, aralkyls Di-substituted with a substituent selected from a group, an aromatic heterocyclic group or an alkenyl group Examples include a group such as a substituted amino group, and these substituents may be further substituted. These substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom to form a ring.

"Divalent group of substituted or unsubstituted aromatic hydrocarbon" represented by A in the general formulas (1), (2) and (4), "Divalent group of substituted or unsubstituted aromatic heterocyclic ring" Or “divalent group of aromatic hydrocarbon”, “divalent group of aromatic heterocyclic ring” or “divalent group of condensed polycyclic aromatic” in “substituted or unsubstituted condensed polycyclic aromatic divalent group”. As `` group '', specifically, phenylene group, biphenylene group, terphenylene group, tetrakisphenylene group, naphthylene group, anthrylene group, phenanthrylene group, fluorenylene group, phenanthrolylene group, indenylene group, pyrenylene group, peryleneylene group, Fluoranthenylene group, triphenylenylene group, pyridinylene group, pyrimidinylene group, quinolylene group, isoquinolylene group, indolylene group, carbazolylene group, quinoxaly Down group, benzimidazolylene alkylene group include a pyrazolylene group, naphthyridinylene group, phenanthrolinyl two alkylene groups, Akurijiniren group, thiophenylene group, benzothiophenyl phenylene group, benzothiazolyl alkylene group, and a dibenzothiophenyl phenylene group.
Here, as “a divalent group of an aromatic heterocycle” in “a divalent group of a substituted or unsubstituted aromatic heterocycle” represented by A in the general formulas (1), (2) and (4) Is preferably a divalent group of a sulfur-containing aromatic heterocyclic ring such as a thiophenylene group, a benzothiophenylene group, a benzothiazolylene group or a dibenzothiophenylene group.

“Divalent group of substituted aromatic hydrocarbon”, “Divalent group of substituted aromatic heterocycle” represented by A in the general formulas (1), (2) and (4) or “Substituted condensed polycyclic aromatic” Specific examples of the “substituent” in the “divalent group” include deuterium atom, trifluoromethyl group, cyano group, nitro group; halogen atom such as fluorine atom, chlorine atom, bromine atom, iodine atom; 1 to 6 carbon atoms such as a group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, and n-hexyl group. A linear or branched alkyl group; a linear or branched alkoxy group having 1 to 6 carbon atoms such as a methoxy group, an ethoxy group or a propyloxy group; an alkenyl group such as an allyl group; a benzyl group; Aralkyl groups such as butylmethyl group and phenethyl group; aryloxy groups such as phenoxy group and tolyloxy group; arylalkoxy groups such as benzyloxy group and phenethyloxy group; phenyl group, biphenylyl group, terphenylyl group, naphthyl group, anthracenyl group, phenanthryl Group, fluorenyl group, indenyl group, pyrenyl group, perylenyl group, fluoranthenyl group, triphenylenyl group and other aromatic hydrocarbon groups or condensed polycyclic aromatic groups; pyridyl group, furanyl group, pyranyl group, thienyl group, furyl group , Pyrrolyl group, thiophenyl group, quinolyl group, isoquinolyl group, benzofuranyl group, benzothiophenyl group, indolyl group, carbazolyl group, benzoxazolyl group, benzothiazolyl group, quinoxalyl group, benzoimidazolyl group, Examples include aromatic heterocyclic groups such as lazolyl group, dibenzofuranyl group, dibenzothiophenyl group and carbolinyl group; aryl vinyl groups such as styryl group and naphthyl vinyl group; groups such as acyl groups such as acetyl group and benzoyl group. These substituents may be further substituted. These substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom to form a ring.

The compound having a phenoxazine ring structure or a phenothiazine ring structure represented by the general formulas (1) to (4) of the present invention is a novel compound, and has an electron blocking ability superior to conventional hole transport materials. In addition, it has excellent amorphous properties and is stable in a thin film state.

The compound having a phenoxazine ring structure or a phenothiazine ring structure represented by the general formulas (1) to (4) of the present invention and a hole injection layer of an organic electroluminescence element (hereinafter abbreviated as an organic EL element) and It can be used as a constituent material for the hole transport layer. By using a material with higher hole injection properties, higher mobility, higher electron blocking properties, and higher electron stability than conventional materials, it is possible to confine excitons generated in the light emitting layer. In addition, the probability of recombination of holes and electrons can be improved, high luminous efficiency can be obtained, the driving voltage is lowered, and the durability of the organic EL element is improved.

The compound having a phenoxazine ring structure or a phenothiazine ring structure represented by the general formulas (1) to (4) of the present invention can also be used as a constituent material of an electron blocking layer of an organic EL device. By using a material with excellent electron blocking ability and hole transportability compared to conventional materials and high stability in the thin film state, the driving voltage is lowered and current resistance is maintained while having high luminous efficiency. Is improved and the maximum light emission luminance of the organic EL element is improved.

The compound having a phenoxazine ring structure or a phenothiazine ring structure represented by the general formulas (1) to (4) of the present invention can also be used as a constituent material of a light emitting layer of an organic EL device. The material of the present invention, which has excellent hole transportability compared to conventional materials and has a wide band gap, is used as a host material for the light-emitting layer, and supports a fluorescent or phosphorescent emitter called a dopant to emit light. By using it as a layer, it has the effect | action that a drive voltage falls and can implement | achieve the organic EL element by which luminous efficiency was improved.

  The organic EL device of the present invention has a higher mobility of holes than a conventional hole transport material, an excellent electron blocking ability, an excellent amorphous property, and a stable thin film state. Since a compound having a ring structure or a phenothiazine ring structure is used, high efficiency and high durability can be realized.

The compound having a phenoxazine ring structure or a phenothiazine ring structure of the present invention is useful as a constituent material of a hole injection layer, a hole transport layer, an electron blocking layer or a light emitting layer of an organic EL device, and has an excellent electron blocking ability. In addition, the amorphous property is good, the thin film state is stable, and the heat resistance is excellent. The organic EL device of the present invention has high luminous efficiency and high power efficiency, which can reduce the practical driving voltage of the device. The emission start voltage can be lowered and the durability can be improved.

1 is a 1H-NMR chart of the compound of Example 1 of the present invention (Compound 34). It is a 1H-NMR chart of the compound of Example 2 of the present invention (Compound 85). FIG. 3 is a 1H-NMR chart of the compound of Example 3 of the present invention (Compound 63). FIG. 6 is a 1H-NMR chart of the compound of Example 4 of the present invention (Compound 86). FIG. 6 is a diagram showing EL element configurations of Example 7 and Comparative Example 1.

The compound having a phenoxazine ring structure or a phenothiazine ring structure of the present invention is a novel compound, and these compounds can be synthesized, for example, as follows. For example, 3-bromo-10-arylphenoxazine is synthesized by bromination of the corresponding 10-position substituted phenoxazine with an aryl group using bromine or N-bromosuccinimide (for example, Non-Patent Document 4). A boronic acid or a boronic acid ester synthesized by a reaction of this bromo compound with pinacolborane, bis (pinacolato) diboron, etc. (for example, see Non-Patent Document 5), and aryl substituted with various diarylamino groups A compound having a phenoxazine ring structure or a phenothiazine ring structure can be synthesized by performing a cross-coupling reaction such as Suzuki coupling with a halide (see, for example, Non-Patent Document 6).

Specific examples of preferable compounds among the compounds having a phenoxazine ring structure or a phenothiazine ring structure represented by the general formula (1) are shown below, but the present invention is not limited to these compounds.

These compounds were purified by column chromatography, adsorption purification using silica gel, activated carbon, activated clay, etc., recrystallization or crystallization using a solvent, and the like. The compound was identified by NMR analysis. As physical properties, glass transition point (Tg), melting point and work function were measured. The glass transition point (Tg) is an index of stability in a thin film state, the melting point is an index of vapor deposition, and the work function is an index of hole transportability.

The glass transition point (Tg) and the melting point were determined with a high-sensitivity differential scanning calorimeter (manufactured by Bruker AXS, DSC3100S) using powder.

The work function was measured using an atmospheric photoelectron spectrometer (AC-3 type, manufactured by Riken Keiki Co., Ltd.) by forming a 100 nm thin film on the ITO substrate.

The structure of the organic EL device of the present invention includes an anode, a hole transport layer, an electron blocking layer, a light-emitting layer, an electron transport layer, and a cathode sequentially on the substrate, and between the anode and the hole transport layer. And those having an electron injection layer between the electron transport layer and the cathode. In these multilayer structures, several organic layers can be omitted. For example, a structure having an anode, a hole transport layer, a light-emitting layer, an electron transport layer, and a cathode sequentially on a substrate can be used. .

As the anode of the organic EL element of the present invention, an electrode material having a large work function such as ITO or gold is used. As a hole injection layer of the organic EL device of the present invention, in addition to a compound having a phenoxazine ring structure or a phenothiazine ring structure represented by the general formula (1) of the present invention, a porphyrin compound typified by copper phthalocyanine, a starburst Materials such as triphenylamine derivatives of various types, various triphenylamine tetramers, acceptor heterocyclic compounds such as hexacyanoazatriphenylene, and coating-type polymer materials can be used. These materials can be formed into a thin film by a known method such as a spin coating method or an ink jet method in addition to a vapor deposition method.

As a hole transport layer of the organic EL device of the present invention, in addition to a compound having a phenoxazine ring structure or a phenothiazine ring structure represented by the general formula (1) of the present invention, N, N′-diphenyl-N, N ′ -Di (m-tolyl) benzidine (hereinafter abbreviated as TPD), N, N'-diphenyl-N, N'-di (α-naphthyl) benzidine (hereinafter abbreviated as NPD), N, N, N Benzidine derivatives such as', N'-tetrabiphenylylbenzidine, 1,1-bis [4- (di-4-tolylamino) phenyl] cyclohexane (hereinafter abbreviated as TAPC), various triphenylamine trimers and A tetramer or the like can be used. These may be formed alone, but may be used as a single layer formed by mixing with other materials, layers formed alone, mixed layers formed, or A stacked structure of layers formed by mixing with a layer formed alone may be used. Further, as a hole injection / transport layer, a coating type such as poly (3,4-ethylenedioxythiophene) (hereinafter abbreviated as PEDOT) / poly (styrene sulfonate) (hereinafter abbreviated as PSS) is used. These polymer materials can be used. These materials can be formed into a thin film by a known method such as a spin coating method or an ink jet method in addition to a vapor deposition method.

In addition, in the hole injection layer or the hole transport layer, a material that is usually used for the layer is further P-doped with trisbromophenylamine hexachloroantimony or the like, or a TPD structure having a partial structure. Molecular compounds and the like can be used.

As the electron blocking layer of the organic EL device of the present invention, in addition to a compound having a phenoxazine ring structure or a phenothiazine ring structure represented by the general formula (1) of the present invention, 4,4 ′, 4 ″ -tri (N -Carbazolyl) triphenylamine (hereinafter abbreviated as TCTA), 9,9-bis [4- (carbazol-9-yl) phenyl] fluorene, 1,3-bis (carbazol-9-yl) benzene (hereinafter, carbazole derivatives such as 2,2-bis (4-carbazol-9-ylphenyl) adamantane (hereinafter abbreviated as Ad-Cz), 9- [4- (carbazol-9-yl) phenyl ] -9- [4- (triphenylsilyl) phenyl] -9H-fluorene represented by a triphenylsilyl group and a compound having a triarylamine structure A compound having an inhibitory action can be used. These may be formed alone, but may be used as a single layer formed by mixing with other materials, layers formed alone, mixed layers formed, or A stacked structure of layers formed by mixing with a layer formed alone may be used. These materials can be formed into a thin film by a known method such as a spin coating method or an ink jet method in addition to a vapor deposition method.

As the light emitting layer of the organic EL device of the present invention, various metal complexes, anthracene derivatives, bisstyrylbenzene derivatives, pyrene derivatives, oxazole derivatives, polyparaphenylene vinylene derivatives, etc., in addition to metal complexes of quinolinol derivatives including Alq ₃ Can be used. Further, the light emitting layer may be composed of a host material and a dopant material. In addition to the compound having a phenoxazine ring structure or a phenothiazine ring structure represented by the general formula (1) of the present invention as the host material, In addition to the materials, thiazole derivatives, benzimidazole derivatives, polydialkylfluorene derivatives, and the like can be used. As the dopant material, quinacridone, coumarin, rubrene, perylene, and derivatives thereof, benzopyran derivatives, rhodamine derivatives, aminostyryl derivatives, and the like can be used. These may be formed alone, but may be used as a single layer formed by mixing with other materials, layers formed alone, mixed layers formed, or A stacked structure of layers formed by mixing with a layer formed alone may be used.

In addition, a phosphorescent material can be used as the light emitting material. As the phosphorescent emitter, a phosphorescent emitter of a metal complex such as iridium or platinum can be used. Green phosphorescent emitters such as Ir (ppy) ₃ , blue phosphorescent emitters such as FIrpic and FIr6, red phosphorescent emitters such as Btp ₂ Ir (acac), and the like are used as host materials. In addition to carbazole derivatives such as 4,4′-di (N-carbazolyl) biphenyl (hereinafter abbreviated as CBP), TCTA, mCP, etc. as a hole injection / transport host material, A compound having a phenoxazine ring structure or a phenothiazine ring structure represented can be used. As an electron transporting host material, p-bis (triphenylsilyl) benzene (hereinafter abbreviated as UGH2) and 2,2 ′, 2 ″-(1,3,5-phenylene) -tris (1-phenyl) -1H-benzimidazole) (hereinafter abbreviated as TPBI) and the like, and a high-performance organic EL device can be produced.

In order to avoid concentration quenching, the host material of the phosphorescent light emitting material is preferably doped by co-evaporation in the range of 1 to 30 weight percent with respect to the entire light emitting layer.

These materials can be formed into a thin film by a known method such as a spin coating method or an ink jet method in addition to a vapor deposition method.

As a hole blocking layer of the organic EL device of the present invention, a phenanthroline derivative such as bathocuproine (hereinafter abbreviated as BCP) or aluminum (III) bis (2-methyl-8-quinolinato) -4-phenylphenolate In addition to metal complexes of quinolinol derivatives such as BAlq), various rare earth complexes, triazole derivatives, triazine derivatives, oxadiazole derivatives, and the like can be used. These materials may also serve as the material for the electron transport layer. These may be formed alone, but may be used as a single layer formed by mixing with other materials, layers formed alone, mixed layers formed, or A stacked structure of layers formed by mixing with a layer formed alone may be used. These materials can be formed into a thin film by a known method such as a spin coating method or an ink jet method in addition to a vapor deposition method.

As an electron transport layer of the organic EL device of the present invention, various metal complexes, triazole derivatives, triazine derivatives, oxadiazole derivatives, thiadiazole derivatives, carbodiimide derivatives, quinoxaline, in addition to metal complexes of quinolinol derivatives including Alq ₃ and BAlq. Derivatives, phenanthroline derivatives, silole derivatives and the like can be used. These may be formed alone, but may be used as a single layer formed by mixing with other materials, layers formed alone, mixed layers formed, or A stacked structure of layers formed by mixing with a layer formed alone may be used. These materials can be formed into a thin film by a known method such as a spin coating method or an ink jet method in addition to a vapor deposition method.

As the electron injection layer of the organic EL device of the present invention, an alkali metal salt such as lithium fluoride and cesium fluoride, an alkaline earth metal salt such as magnesium fluoride, and a metal oxide such as aluminum oxide can be used. In the preferred selection of the electron transport layer and the cathode, this can be omitted.

As the cathode of the organic EL device of the present invention, an electrode material having a low work function such as aluminum or an alloy having a lower work function such as a magnesium silver alloy, a magnesium indium alloy, or an aluminum magnesium alloy is used as the electrode material.

Hereinafter, embodiments of the present invention will be specifically described with reference to examples. However, the present invention is not limited to the following examples.

<Synthesis of 3- [4- [bis (biphenyl-4-yl) amino] -phenyl] -10-phenyl-10H-phenoxazine (Compound 34)>
In a reaction vessel purged with nitrogen, 2.4 g of 10-phenyl-3- (4,4,5,5-tetramethyl- [1,3,2] dioxoborane-2-yl) -10H-phenoxazine, bis (biphenyl) -4-yl)-(4-bromophenyl) amine (2.9 g), toluene (40 ml), ethanol (10 ml), and 2M aqueous potassium carbonate solution (9 ml) were added, and nitrogen gas was bubbled for 30 minutes while irradiating ultrasonic waves. Tetrakis (triphenylphosphine) palladium (0.36 g) was added and heated, followed by stirring at 72 ° C. for 8.5 hours. The mixture was allowed to cool to room temperature, and the precipitated solid was collected by filtration, and then washed successively with water, toluene, and methanol to obtain a pale yellowish white crude product. 120 ml of toluene was added to the crude product to dissolve it, and after adsorption purification using 12.5 g of silica gel, the product was concentrated under reduced pressure to obtain a pale yellowish white powder. By refining the pale yellowish white powder by recrystallization using a mixed solvent of toluene / methanol twice, 3- [4- [bis (biphenyl-4-yl) amino] -phenyl] -10-phenyl A pale yellowish white powder of -10H-phenoxazine 2.2 g (yield 50%) was obtained.

  The structure of the obtained pale yellowish white powder was identified using NMR. The result of 1H-NMR measurement is shown in FIG.

The following 34 hydrogen signals were detected by 1H-NMR (THF-d ₈ ). δ (ppm) = 5.91 (1H), 5.92 (1H), 6.54-6.64 (2H), 6.66-6.69 (1H), 6.86-6.89 (1H ), 7.00 (1H), 7.13-7.21 (6H), 7.24-7.28 (2H), 7.35-7.42 (6H), 7.44-7.53 ( 3H), 7.53-7.58 (4H), 7.58-7.66 (6H).

<Synthesis of 3- [4- [bis (biphenyl-4-yl) amino] -phenyl] -10-phenyl-10H-phenothiazine (Compound 85)>
In a reaction vessel purged with nitrogen, 2.4 g of 10-phenyl-3- (4,4,5,5-tetramethyl- [1,3,2] dioxoborane-2-yl) -10H-phenothiazine, bis (biphenyl- 4-yl)-(4-bromophenyl) amine (2.9 g), toluene (40 ml), ethanol (10 ml), and 2M aqueous potassium carbonate solution (9 ml) were added, and nitrogen gas was bubbled for 30 minutes while irradiating ultrasonic waves. Tetrakis (triphenylphosphine) palladium (0.35 g) was added and heated, followed by stirring at 72 ° C. for 6 hours. The mixture was allowed to cool to room temperature, and the precipitated solid was collected by filtration, and then washed sequentially with water, toluene, and methanol to obtain a tan crude product. The crude product was dissolved by adding 180 ml of toluene, subjected to adsorption purification using 30 g of silica gel, and then concentrated under reduced pressure to obtain a pale yellowish white powder. By refining the pale yellowish white powder by recrystallization using a mixed solvent of toluene / methanol three times, 3- [4- [bis (biphenyl-4-yl) amino] -phenyl] -10-phenyl A pale yellowish white powder of -10H-phenothiazine (2.4 g, yield 61%) was obtained.

  The structure of the obtained pale yellowish white powder was identified using NMR. The results of 1H-NMR measurement are shown in FIG.

The following 34 hydrogen signals were detected by 1H-NMR (THF-d ₈ ). δ (ppm) = 6.17-6.25 (2H), 6.76-6.84 (2H), 6.98-7.21 (1H), 7.08-7.11 (1H), 7 .14-7.21 (6H), 7.24-7.30 (3H), 7.38 (4H), 7.42-7.47 (4H), 7.48-7.66 (11H).

Synthesis of <3- [4-[(biphenyl-4-yl)-(9,9-dimethyl-9H-fluoren-2-yl) amino] -phenyl] -10-phenyl-10H-phenoxazine (Compound 63) >
To a reaction vessel purged with nitrogen, 2.4 g of 10-phenyl-3- (4,4,5,5-tetramethyl- [1,3,2] dioxoborane-2-yl) -10H-phenoxazine, (biphenyl- 4-yl)-(4-bromophenyl)-(9,9-dimethyl-9H-fluoren-2-yl) amine 3.2 g, toluene 44 ml, ethanol 11 ml, 2M aqueous potassium carbonate solution 9 ml were added and irradiated with ultrasound. Then, nitrogen gas was bubbled for 30 minutes. Tetrakis (triphenylphosphine) palladium (0.36 g) was added and heated, followed by stirring at 72 ° C. for 5.5 hours. After allowing to cool to room temperature, 120 ml of toluene and 100 ml of water were added for extraction, and the organic layer was dried over magnesium sulfate and then concentrated under reduced pressure to obtain a brown crude product. The crude product was purified by column chromatography (carrier: silica gel, eluent: cyclohexane / toluene) and 3- [4-[(biphenyl-4-yl)-(9,9-dimethyl-9H-fluoren-2-yl). ) Amino] -phenyl] -10-phenyl-10H-phenoxazine 2.3 g (yield 54%) of pale yellowish white powder was obtained.

  The structure of the obtained pale yellowish white powder was identified using NMR. The results of 1H-NMR measurement are shown in FIG.

The following 38 signals of hydrogen were detected by 1H-NMR (THF-d ₈ ). δ (ppm) = 1.41 (6H), 5.90-5.94 (1H), 5.96 (1H), 6.54-6.64 (2H), 6.66-6.69 (1H ), 6.85-6.90 (1H), 7.01 (1H), 7.05-7.09 (1H), 7.13-7.28 (7H), 7.33 (1H), 7 .35-7.43 (5H), 7.43-7.57 (5H), 7.59-7.68 (6H).

<Synthesis of 3- [4-[(biphenyl-4-yl)-(9,9-dimethyl-9H-fluoren-2-yl) amino] -phenyl] -10-phenyl-10H-phenothiazine (Compound 86)>
Into a nitrogen-substituted reaction vessel, 0.9 g of 10-phenyl-3- (4,4,5,5-tetramethyl- [1,3,2] dioxoborane-2-yl) -10H-phenothiazine, (biphenyl-4 -Il)-(4-Bromophenyl)-(9,9-dimethyl-9H-fluoren-2-yl) Amine 1.2g, toluene 20ml, ethanol 5ml, 2M aqueous potassium carbonate solution 4ml were added and irradiated with ultrasound. Then, nitrogen gas was bubbled for 30 minutes. Tetrakis (triphenylphosphine) palladium (0.13 g) was added and heated, followed by stirring at 72 ° C. for 7 hours. After cooling to room temperature, extraction was performed by adding 100 ml of toluene and 100 ml of water, and the organic layer was dried over magnesium sulfate and concentrated under reduced pressure to obtain a brown crude product. The crude product was purified by column chromatography (carrier: silica gel, eluent: cyclohexane / toluene) and 3- [4-[(biphenyl-4-yl)-(9,9-dimethyl-9H-fluoren-2-yl). ) Amino] -phenyl] -10-phenyl-10H-phenothiazine (1.4 g, yield 82%) was obtained as a yellow powder.

  The structure of the obtained yellow powder was identified using NMR. The result of 1H-NMR measurement is shown in FIG.

The following 38 signals of hydrogen were detected by 1H-NMR (THF-d ₈ ). δ (ppm) = 1.41 (6H), 6.18 (1H), 6.23 (1H), 6.76-6.84 (2H), 6.98-7.02 (1H), 7. 05-7.12 (2H), 7.14-7.28 (7H), 7.30 (1H), 7.33 (1H), 7.36-7.48 (7H), 7.49-7 .57 (3H), 7.59-7.69 (6H).

About the compound of this invention, melting | fusing point and the glass transition point were calculated | required with the highly sensitive differential scanning calorimeter (The product made from Bruker AXS, DSC3100S).
Melting point Glass transition point
Inventive Example 1 Compound 277 ° C. 115 ° C.
Compound of Invention Example 2 258 ° C. 114 ° C.
Compound of Invention Example 3 154 ° C. 130 ° C.
Inventive Example 4 Compound 149 ° C. 122 ° C.

The compound of the present invention has a glass transition point of 100 ° C. or higher, which indicates that the thin film state is stable in the compound of the present invention.

Using the compound of the present invention, a deposited film having a thickness of 100 nm was formed on an ITO substrate, and the work function was measured with an atmospheric photoelectron spectrometer (AC-3 type, manufactured by Riken Keiki Co., Ltd.).
Work Function Compound of the Invention Example 1 5.32 eV
Compound of Example 2 of the present invention 5.40 eV
Inventive Example 3 compound 5.31 eV
Inventive Example 4 Compound 5.31 eV

Thus, the compound of the present invention exhibits a suitable energy level as compared with the work function 5.4 eV of general hole transport materials such as NPD and TPD, and has a good hole transport capability. You can see that

As shown in FIG. 5, the organic EL element has a hole injection layer 3, a hole transport layer 4, a light emitting layer 5, and an electron transport layer on a glass substrate 1 on which an ITO electrode is previously formed as a transparent anode 2. 6, an electron injection layer 7 and a cathode (aluminum electrode) 8 were deposited in this order.

Specifically, the glass substrate 1 on which ITO having a thickness of 150 nm was formed was washed with an organic solvent, and then the surface was washed by oxygen plasma treatment. Then, this glass substrate with an ITO electrode was mounted in a vacuum vapor deposition machine and the pressure was reduced to 0.001 Pa or less. Subsequently, a compound 98 having the following structural formula was formed to a thickness of 20 nm as the hole injection layer 3 so as to cover the transparent anode 2. On the hole injection layer 3, the compound (Compound 85) of Example 2 of the present invention was formed as the hole transport layer 4 so as to have a film thickness of 40 nm. On the hole transport layer 4, the compound 99 having the following structural formula and the compound 100 having the following structural formula are deposited as the light emitting layer 5 at a deposition rate in which the deposition rate ratio is compound 99: compound 100 = 5: 95. To form a film thickness of 30 nm. On this emitting layer 5 was formed to have the Alq ₃ film thickness 30nm as an electron transport layer 6. On the electron transport layer 6, lithium fluoride was formed as the electron injection layer 7 so as to have a film thickness of 0.5 nm. Finally, aluminum was deposited to a thickness of 150 nm to form the cathode 8. About the produced organic EL element, the characteristic measurement was performed at normal temperature in air | atmosphere.

Table 1 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the organic EL device produced using the compound of Example 2 (Compound 85) of the present invention.

[Comparative Example 1]
For comparison, in Example 7, except that the compound 101 of the following structural formula was formed to a film thickness of 40 nm instead of the compound of Example 2 of the present invention (Compound 85) as the material of the hole transport layer 4. An organic EL element was produced under the same conditions. About the produced organic EL element, the characteristic measurement was performed at normal temperature in air | atmosphere. Table 1 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the produced organic EL element.

As shown in Table 1, the driving voltage when a current density of 10 mA / cm ² was passed was 5.94 V for compound 101, and 4.94 V for the compound of Example 2 of the present invention (compound 85). And the voltage was lowered. The power efficiency was also improved to 5.84 lm / W for the compound of Example 2 of the present invention (Compound 85), compared to 5.49 lm / W for Compound 101.

As is clear from the above results, the organic EL device using the compound having the phenoxazine ring structure or the phenothiazine ring structure of the present invention has a light emission efficiency and power as compared with the organic EL device using the compound 101. It was found that the efficiency can be improved and the practical driving voltage can be lowered.

The results of measuring the light emission starting voltage using the same organic EL element as described above are shown below.

Organic EL device Compound Luminescence start voltage [V]
Example 7 Compound 85 2.8
Comparative Example 1 Compound 101 2.9

As a result, it can be seen that the light emission starting voltage is lowered in Example 7 using the compound of Example 2 of the present invention (Compound 85) as compared to Comparative Example 1 using Compound 101.

The compound having a compound having a phenoxazine ring structure or a phenothiazine ring structure of the present invention is excellent as a compound for an organic EL device because it has a high hole transport capability, excellent amorphous properties, and a stable thin film state. Yes. By producing an organic EL device using the compound, high luminous efficiency and power efficiency can be obtained, practical driving voltage can be lowered, and durability can be improved. For example, it has become possible to develop home appliances and lighting.

DESCRIPTION OF SYMBOLS 1 Glass substrate 2 Transparent anode 3 Hole injection layer 4 Hole transport layer 5 Light emitting layer 6 Electron transport layer 7 Electron injection layer 8 Cathode

Claims (9)

A compound having a phenoxazine ring structure or a phenothiazine ring structure represented by the following general formula (1).

Wherein X is an oxygen atom or a sulfur atom, and A is a substituted or unsubstituted aromatic hydrocarbon, a substituted or unsubstituted aromatic heterocyclic ring or a substituted or unsubstituted condensed polycyclic aromatic divalent group. Ar 1, Ar 2, Ar 3 may be the same or different from each other, and are substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic heterocyclic groups, or substituted or unsubstituted condensed polycyclic aromatics Here, Ar2 and Ar3 may be directly bonded to each other via a single bond or a substituted or unsubstituted methylene group to form a ring, and the substituents of Ar2 and Ar3 may be a single bond, substituted or A ring may be bonded to each other via an unsubstituted methylene group, an oxygen atom or a sulfur atom, and R1 to R7 may be the same as or different from each other, and may be a hydrogen atom, a deuterium atom or a fluorine atom. A chlorine atom, a cyano group, a trifluoromethyl group, a nitro group, an optionally substituted linear or branched alkyl group having 1 to 6 carbon atoms, and an optionally substituted carbon A cycloalkyl group having 5 to 10 atoms, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent, and 1 to 1 carbon atoms which may have a substituent. 6 linear or branched alkyloxy groups, optionally substituted cycloalkyloxy groups having 5 to 10 carbon atoms, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted An aromatic heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group, or a substituted or unsubstituted aryloxy group, which has a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom; It may be bonded to each other to form a ring with.) A compound represented by the following general formula (2) having a phenoxazine ring structure or a phenothiazine ring structure.

Wherein X is an oxygen atom or a sulfur atom, and A is a substituted or unsubstituted aromatic hydrocarbon, a substituted or unsubstituted aromatic heterocyclic ring or a substituted or unsubstituted condensed polycyclic aromatic divalent group. Ar 1, Ar 2, Ar 3 may be the same or different from each other, and are substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic heterocyclic groups, or substituted or unsubstituted condensed polycyclic aromatics Here, Ar2 and Ar3 may be directly bonded to each other via a single bond or a substituted or unsubstituted methylene group to form a ring, and the substituents of Ar2 and Ar3 may be a single bond, substituted or A ring may be bonded to each other via an unsubstituted methylene group, an oxygen atom or a sulfur atom, and R1 to R7 may be the same as or different from each other, and may be a hydrogen atom, a deuterium atom or a fluorine atom. A chlorine atom, a cyano group, a trifluoromethyl group, a nitro group, an optionally substituted linear or branched alkyl group having 1 to 6 carbon atoms, and an optionally substituted carbon A cycloalkyl group having 5 to 10 atoms, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent, and 1 to 1 carbon atoms which may have a substituent. 6 linear or branched alkyloxy groups, optionally substituted cycloalkyloxy groups having 5 to 10 carbon atoms, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted Aromatic heterocyclic group, substituted or unsubstituted condensed polycyclic aromatic group or substituted or unsubstituted aryloxy group, wherein R1 and R2, R2 and R3, R3 and R4, R6 and R7 are single bonds, substituted if Unsubstituted methylene group, via an oxygen atom or a sulfur atom may be bonded to each other to form a ring.) A compound having a phenoxazine ring structure or a phenothiazine ring structure represented by the following general formula (3).

(In the formula, X is an oxygen atom or a sulfur atom, and Ar1, Ar2, and Ar3 may be the same or different from each other, and are substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic heterocyclic groups. Or a substituted or unsubstituted condensed polycyclic aromatic group, wherein Ar2 and Ar3 may be directly bonded to each other via a single bond or a substituted or unsubstituted methylene group to form a ring; , Ar3 substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom, and R1 to R11 may be the same or different from each other; A straight or branched alkyl group having 1 to 6 carbon atoms which may have a hydrogen atom, deuterium atom, fluorine atom, chlorine atom, cyano group, trifluoromethyl group, nitro group or substituent. A cycloalkyl group having 5 to 10 carbon atoms which may have a substituent, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent, a substituent A linear or branched alkyloxy group having 1 to 6 carbon atoms which may have a group, a cycloalkyloxy group having 5 to 10 carbon atoms which may have a substituent, substituted or unsubstituted A substituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group, or a substituted or unsubstituted aryloxy group, R1 and R2, R2 and R3 R3 and R4, R6 and R7, R8 and R9, R10 and R11 may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom. A compound represented by the following general formula (4) having a phenoxazine ring structure or a phenothiazine ring structure.

Wherein X is an oxygen atom or a sulfur atom, and A is a substituted or unsubstituted aromatic hydrocarbon, a substituted or unsubstituted aromatic heterocyclic ring or a substituted or unsubstituted condensed polycyclic aromatic divalent group. Ar2 and Ar3 may be the same or different from each other, and represent a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted condensed polycyclic aromatic group. Here, Ar2 and Ar3 may be directly bonded to each other through a single bond or a substituted or unsubstituted methylene group to form a ring, and the substituents of Ar2 and Ar3 are a single bond, substituted or unsubstituted. R1 to R7 and R12 to R16 may be the same as or different from each other through a methylene group, an oxygen atom or a sulfur atom, and may be a hydrogen atom, a deuterium atom, a fluorine atom. A linear or branched alkyl group having 1 to 6 carbon atoms which may have a primary atom, a chlorine atom, a cyano group, a trifluoromethyl group, a nitro group, or a substituent; A cycloalkyl group having 5 to 10 carbon atoms, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent, and a carbon atom which may have a substituent A linear or branched alkyloxy group having 1 to 6 carbon atoms, an optionally substituted cycloalkyloxy group having 5 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group, substituted or An unsubstituted aromatic heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group or a substituted or unsubstituted aryloxy group, R1 and R2, R2 and R3, R3 and R4, R6 and R7, R12 When 13, R13 and R14, R14 and R15, R15 and R16 is a single bond, a substituted or unsubstituted methylene group, linked to each other through an oxygen atom or a sulfur atom may form a ring.) In the organic electroluminescence device having at least one organic layer sandwiched between a pair of electrodes, the compound having a phenoxazine ring structure or a phenothiazine ring structure according to any one of claims 1 to 4 is formed of at least one organic layer. An organic electroluminescence element characterized by being used as a constituent material.   6. The organic electroluminescence device according to claim 5, wherein the organic layer is a hole transport layer.   6. The organic electroluminescence device according to claim 5, wherein the organic layer is an electron blocking layer.   6. The organic electroluminescence device according to claim 5, wherein the organic layer is a hole injection layer.   The organic electroluminescence device according to claim 5, wherein the organic layer is a light emitting layer.

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