JP2015155378A - Compound having triphenylene ring structure and organic electroluminescent element - Google Patents

Abstract

[PROBLEMS] As a material for an organic electroluminescence device having high efficiency and high durability, it has excellent hole injection / transport performance, electron blocking ability, high stability in a thin film state, and excellent heat resistance. Provision of organic compounds having characteristics. A compound having a triphenylene ring structure represented by formula (1). (In the formula, Ar1 and Ar2 are a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group or a substituted or unsubstituted condensed polycyclic aromatic group, and R1, R2, R3 Is a substituent, and r1, r2, and r3 may be the same or different from each other, r1, r2 represents 0 or an integer of 1 to 4, and r3 represents an integer of 0 or 1 to 3). Selection diagram] None

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 to the element. Specifically, the present invention relates to a compound having a triphenylene ring structure and organic electroluminescence using the compound. The present invention relates to a luminescence element.

  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. Because of insufficient electron blocking properties, some of the electrons pass through the light emitting layer and cannot be expected to improve luminous efficiency. For higher efficiency, the electron blocking properties are higher and the thin film is more stable. Therefore, a material having high heat resistance has been demanded.

As compounds having improved properties such as heat resistance and hole injection properties, arylamine compounds having a substituted triphenylene structure represented by the following formula (for example, Compound A and Compound B) have been proposed. (For example, see Patent Documents 3 and 4).

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 further lower drive voltage and higher light emission efficiency while enhancing amorphousness.

JP-A-8-48656 Japanese Patent No. 3194657 WO2010 / 002850 publication WO2011 / 081423

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) Org. Synth. , 10, 423 (2002)

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 that the organic compound to be provided by the present invention should have include (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 object, the inventors of the present invention have a high hole injection / transport capability of the aromatic tertiary amine structure, and the heat resistance and thin film stability of the triphenylene structure. As a result of designing and chemically synthesizing a compound having a triphenylene ring structure, making various organic electroluminescent devices using the compound, and intensively evaluating the characteristics of the devices, the present invention was completed. It came.

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

(In the formula, Ar ₁ and Ar ₂ 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. Which may be bonded to each other through a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a nitrogen atom, and R ₁ , R ₂ and R ₃ may be the same as each other; May be different, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent, and a substituent. An optionally substituted cycloalkyl group having 5 to 10 carbon atoms, an optionally substituted linear or branched alkenyl group having 2 to 6 carbon atoms, and a substituent. A straight of 1 to 6 carbon atoms Or branched alkyloxy group, optionally substituted cycloalkyloxy group having 5 to 10 carbon atoms, substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aromatic heterocycle Di having a substituent selected from a group, a substituted or unsubstituted condensed polycyclic aromatic group, a substituted or unsubstituted aryloxy group, or an aromatic hydrocarbon group, an aromatic heterocyclic group, and a condensed polycyclic aromatic group Represents a substituted amino group, r ₁ , r ₂ and r ₃ may be the same or different from each other; r ₁ and r ₂ represent 0 or an integer of 1 to 4; and r ₃ represents an integer of 0 or 1 to 3 Here, when a plurality of R ₁ , R ₂ and R ₃ are bonded to the same benzene ring (when r ₁ , r ₂ or r ₃ is 2 or more), they may be the same or different from each other. It shall be good.)

Moreover, this invention is a compound which has a triphenylene ring structure represented by following General formula (2).

(In the formula, Ar ₁ and Ar ₂ 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. Which may be bonded to each other through a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a nitrogen atom, and R ₁ , R ₂ and R ₃ may be the same as each other; May be different, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent, and a substituent. An optionally substituted cycloalkyl group having 5 to 10 carbon atoms, an optionally substituted linear or branched alkenyl group having 2 to 6 carbon atoms, and a substituent. A straight of 1 to 6 carbon atoms Or branched alkyloxy group, optionally substituted cycloalkyloxy group having 5 to 10 carbon atoms, substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aromatic heterocycle Di having a substituent selected from a group, a substituted or unsubstituted condensed polycyclic aromatic group, a substituted or unsubstituted aryloxy group, or an aromatic hydrocarbon group, an aromatic heterocyclic group, and a condensed polycyclic aromatic group Represents a substituted amino group, r ₁ , r ₂ and r ₃ may be the same or different from each other; r ₁ and r ₂ represent 0 or an integer of 1 to 4; and r ₃ represents an integer of 0 or 1 to 3 Here, when a plurality of R ₁ , R ₂ and R ₃ are bonded to the same benzene ring (when r ₁ , r ₂ or r ₃ is 2 or more), they may be the same or different from each other. It shall be good.)

In the organic electroluminescence device having a pair of electrodes and at least one organic layer sandwiched therebetween, the compound having a triphenylene ring structure represented by the general formula (1) or the general formula (2) is provided. The organic electroluminescence device is used as a constituent material of at least one organic layer.

“Substituted or unsubstituted aromatic hydrocarbon group”, “substituted or unsubstituted aromatic heterocyclic group” or “substituted or unsubstituted” represented by Ar ₁ or Ar ₂ in the general formulas (1) to (2) As the “aromatic hydrocarbon group”, “aromatic heterocyclic group” or “fused polycyclic aromatic group” in the substituted condensed polycyclic aromatic group, specifically, a phenyl group, a biphenylyl group, a terphenylyl group, Naphthyl, anthryl, phenanthryl, fluorenyl, indenyl, pyrenyl, perylenyl, fluoranthenyl, triphenylenyl, pyridyl, furanyl, pyranyl, thienyl, quinolyl, isoquinolyl, benzofuranyl, Benzothienyl, indolyl, carbazolyl, benzoxazolyl, benzothiazolyl, quinoxalyl, benzimi Zoriru group, a pyrazolyl group, a dibenzofuranyl group, dibenzothienyl group, carbolinyl group, and the like 9,10-dihydro acridinyl group.
In addition, “substituted or unsubstituted aromatic hydrocarbon group”, “substituted or unsubstituted aromatic heterocyclic group” or “substituted or unsubstituted condensed polycyclic aromatic group” represented by Ar ₁ and Ar ₂ The “aromatic hydrocarbon group”, “aromatic heterocyclic group” or “fused polycyclic aromatic group” in the above formulas are directly bonded to each other through a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom. They may combine to form a ring.
Here, as the bonding position of the “substituted or unsubstituted aromatic heterocyclic group” represented by Ar ₁ and Ar ₂ in the general formulas (1) to (2), the carbon atom of the “aromatic heterocyclic group” From the viewpoint of stability and heat resistance.
The “aromatic heterocyclic group” in the “substituted or unsubstituted aromatic heterocyclic group” represented by Ar ₁ and Ar ₂ in the general formulas (1) to (2) is a furanyl group or a benzofuranyl group. Oxygen-containing aromatic heterocyclic groups such as benzoxazolyl and dibenzofuranyl or sulfur-containing aromatic heterocyclic groups such as thienyl, benzothienyl, benzothiazolyl and dibenzothienyl, N-phenylcarbazolyl Group, N-phenyl-9,10-dihydroacridinyl group is preferable, and sulfur-containing aromatic heterocyclic group is particularly preferable.

“Substitution” in the “substituted aromatic hydrocarbon group”, “substituted aromatic heterocyclic group” or “substituted condensed polycyclic aromatic group” represented by Ar ₁ and Ar ₂ in the general formulas (1) to (2) Specific examples of the “group” include 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 A linear or branched alkyl group having 1 to 6 carbon atoms such as isopropyl group, n-butyl group, isobutyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, n-hexyl group, etc. 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 or a naphthylmethyl group; Aralkyl groups such as 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 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 Quinolyl group, isoquinolyl group, benzofuranyl group, benzothienyl group, indolyl group, carbazolyl group, benzoxazolyl group, benzothiazolyl group, quinoxalyl group, benzoimidazolyl group, pyrazolyl group, dibenzofuranyl group, di An aromatic heterocyclic group such as an nzothienyl group and a carbolinyl group; an aryl vinyl group such as a styryl group and a naphthyl vinyl group; and a group such as an acyl group such as an acetyl group and a benzoyl group. It may be replaced. In addition, these substituents are substituted with each other or with a “substituted aromatic hydrocarbon group”, “substituted aromatic heterocyclic group” or “substituted condensed polycyclic aromatic group” represented by Ar ₁ or Ar _2. May be bonded to each other via 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 which may have a substituent” represented by R ₁ , R ₂ or R ₃ in the general formulas (1) to (2) , “Optionally substituted cycloalkyl group having 5 to 10 carbon atoms” or “optionally substituted linear or branched alkenyl group having 2 to 6 carbon atoms” "C1-C6 linear or branched alkyl group", "C5-C10 cycloalkyl group" or "C2-C6 linear or branched alkenyl group" Specifically, 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. , Cyclope Butyl group, a cyclohexyl group, 1-adamantyl, 2-adamantyl, vinyl group, allyl group, isopropenyl group include a 2-butenyl 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.

“A linear or branched alkyl group having 1 to 6 carbon atoms having a substituent” represented by R ₁ , R ₂ or R ₃ in the general formulas (1) to (2); Specific examples of the “substituent” in the “cycloalkyl group having 5 to 10 carbon atoms” or the “straight-chain or branched alkenyl group having 2 to 6 carbon atoms having a substituent” specifically include a deuterium atom. , 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; phenyl groups and biphenyls An aromatic hydrocarbon group or condensed polycyclic aromatic group such as an alkyl group, a terphenylyl group, a naphthyl group, an anthracenyl group, a phenanthryl group, a fluorenyl group, an indenyl group, a pyrenyl group, a perylenyl group, a fluoranthenyl group, or a triphenylenyl group; Group, furanyl group, pyranyl group, thienyl group, furyl group, pyrrolyl group, quinolyl group, isoquinolyl group, benzofuranyl group, benzothienyl group, indolyl group, carbazolyl group, benzoxazolyl group, benzothiazolyl group, quinoxalyl group, benzoimidazolyl group A group such as an aromatic heterocyclic group such as a pyrazolyl group, a dibenzofuranyl group, a dibenzothienyl group and a carbolinyl group, 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.

The linear or branched alkyloxy group having 1 to 6 carbon atoms which may have a substituent represented by R ₁ , R ₂ or R ₃ in the general formulas (1) to (2) Or “a linear or branched alkyloxy group having 1 to 6 carbon atoms” or “5 carbon atoms” in the “optionally substituted cycloalkyloxy group having 5 to 10 carbon atoms”. Specific examples of the “10 to cycloalkyloxy group” include methyloxy group, ethyloxy group, n-propyloxy group, isopropyloxy group, n-butyloxy group, tert-butyloxy group, n-pentyloxy group, n- Hexyloxy group, cyclopentyloxy group, cyclohexyloxy group, cycloheptyloxy group, cyclooctyloxy group, 1-adamantyloxy group, 2-adap Such as it is possible to increase the Nchiruokishi 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 R ₁ , R ₂ , R ₃ in the general formulas (1) to (2) or “substituent” Specific examples of the “substituent” in the cycloalkyloxy group having 5 to 10 carbon atoms having the following: deuterium atom, cyano group, nitro group; halogen such as fluorine atom, chlorine atom, bromine atom, 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, anthracenyl group, phenane Aryl, fluorenyl, indenyl, pyrenyl, perylenyl, fluoranthenyl, triphenylenyl, and other aromatic hydrocarbon groups or condensed polycyclic aromatic groups; pyridyl, furanyl, pyranyl, thienyl, furyl Group, pyrrolyl group, quinolyl group, isoquinolyl group, benzofuranyl group, benzothienyl group, indolyl group, carbazolyl group, benzoxazolyl group, benzothiazolyl group, quinoxalyl group, benzoimidazolyl group, pyrazolyl group, dibenzofuranyl group, dibenzothienyl group And a group such as an aromatic heterocyclic group such as a carbolinyl group, 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 R ₁ , R ₂ , R ₃ in the general formulas (1) to (2) or “ As the “aromatic hydrocarbon group”, “aromatic heterocyclic group” or “fused polycyclic aromatic group” in the “substituted or unsubstituted condensed polycyclic aromatic group”, specifically, a phenyl group, a 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, thienyl group, quinolyl group, isoquinolyl group, Benzofuranyl group, benzothienyl group, indolyl group, carbazolyl group, benzoxazolyl group, benzothiazolyl group, quinoxalyl group, benzo Imidazolyl group, a pyrazolyl group, a dibenzofuranyl group, dibenzothienyl group, and the like 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.
Here, as the bonding position of the “substituted or unsubstituted aromatic heterocyclic group” represented by R ₁ , R ₂ , R ₃ in the general formulas (1) to (2), “aromatic heterocyclic group” It is preferable from the viewpoints of stability and heat resistance to bond to the carbon atom.

“Substituted aromatic hydrocarbon group”, “substituted aromatic heterocyclic group” or “substituted condensed polycyclic aromatic group” represented by R ₁ , R ₂ , R ₃ in the general formulas (1) to (2) Specific examples of the “substituent” in are: 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 Linear or branched having 1 to 6 carbon atoms such as -propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, n-hexyl group An alkyl group of 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 or a naphthylmethyl group; Groups, aralkyl groups such as phenethyl 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 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, thiophenyl, quinolyl, isoquinolyl, benzofuranyl, benzothienyl, indolyl, carbazolyl, benzoxazolyl, benzothiazolyl, quinoxalyl, benzoimidazolyl, pyrazolyl, dibe Examples include aromatic heterocyclic groups such as nzofuranyl group, dibenzothienyl group and carbolinyl group; aryl vinyl groups such as styryl group and naphthyl vinyl group; and groups such as acyl groups such as acetyl group and benzoyl group. The substituent may be further substituted.

Specific examples of the “aryloxy group” in the “substituted or unsubstituted aryloxy group” represented by R ₁ , R ₂ and R ₃ in the general formulas (1) to (2) include a phenoxy group and biphenyl. Examples thereof include a aryloxy group, a terphenylyloxy group, a naphthyloxy group, an anthryloxy group, a phenanthryloxy group, a fluorenyloxy group, an indenyloxy group, a pyrenyloxy group, and a perylenyloxy 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.

Specific examples of the “substituent” in the “substituted aryloxy group” represented by R ₁ , R ₂ and R ₃ in the general formulas (1) to (2) include a deuterium atom, a 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 group, n-butyl group, isobutyl group, tert-butyl group, n A linear or branched alkyl group having 1 to 6 carbon atoms such as a pentyl group, isopentyl group, neopentyl group or n-hexyl group; 1 to 6 carbon atoms such as a methoxy group, an ethoxy group or a propyloxy group A linear or branched alkoxy group; an alkenyl group such as an allyl group; an aralkyl group such as a benzyl group, a naphthylmethyl group, or a phenethyl group; a phenoxy group, a Aryloxy groups such as ruoxy 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 Aromatic hydrocarbon groups or condensed polycyclic aromatic groups such as fluoranthenyl group and triphenylenyl group; pyridyl group, furanyl group, pyranyl group, thienyl group, furyl group, pyrrolyl group, quinolyl group, isoquinolyl group, benzofuranyl group, Aromatic heterocyclic groups such as benzothienyl, indolyl, carbazolyl, benzoxazolyl, benzothiazolyl, quinoxalyl, benzimidazolyl, pyrazolyl, dibenzofuranyl, dibenzothienyl, carbolinyl 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; aromatic hydrocarbon groups such as diphenylamino groups and dinaphthylamino groups; Or a disubstituted amino group substituted with a condensed polycyclic aromatic group; a diaralkylamino group such as a dibenzylamino group or a diphenethylamino group; an aromatic heterocyclic group such as a dipyridylamino group or a dithienylamino group A di-substituted amino group; a dialkenylamino group such as a diallylamino group; a substituent selected from an alkyl group, an aromatic hydrocarbon group, a condensed polycyclic aromatic group, an aralkyl group, an aromatic heterocyclic group or an alkenyl group; Groups such as substituted di-substituted amino groups, and these substituents can be further substituted It may be. 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.

“Di having a substituent selected from an aromatic hydrocarbon group, an aromatic heterocyclic group, and a condensed polycyclic aromatic group represented by R ₁ , R ₂ , R ₃ in the general formulas (1) to (2)” The “aromatic hydrocarbon group”, “aromatic heterocyclic group” or “condensed polycyclic aromatic group” in the “substituted amino group” is the same group as those described above for Ar ₁ and Ar ₂ , The substituents that these groups may have are the same as those shown for Ar ₁ and Ar ₂ .

The compound having a triphenylene ring structure represented by the general formula (1) of the present invention is a novel compound, and has a superior electron blocking ability and superior amorphousness than conventional hole transport materials. In addition, the thin film state is stable.

The compound having a triphenylene ring structure represented by the general formula (1) of the present invention is a constituent material of a hole injection layer and / or a hole transport layer of an organic electroluminescence element (hereinafter abbreviated as an organic EL element). Can be used as 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 triphenylene ring structure represented by the general formula (1) 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 triphenylene ring structure represented by the general formula (1) 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 is a triphenylene ring having a higher hole mobility than that of 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 structure is used, high efficiency and high durability can be realized.

The compound having a triphenylene ring structure represented by the general formula (1) 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 is excellent. It has the ability to block electrons, has good amorphous properties, is stable in a thin film state, and has excellent heat resistance. 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.

1 is a ¹ H-NMR chart of the compound of Example 1 of the present invention (Compound 4). FIG. 3 is a ¹ H-NMR chart of the compound of Example 2 of the present invention (Compound 14). FIG. 3 is a ¹ H-NMR chart of the compound of Example 3 of the present invention (Compound 33). FIG. 6 is a ¹ H-NMR chart of the compound of Example 4 of the present invention (Compound 35). FIG. 6 is a diagram showing EL element configurations of Example 7 and Comparative Example 1.

The compound having a triphenylene ring structure of the present invention is a novel compound, and these compounds can be synthesized, for example, as follows. First, a compound having a triphenylene ring structure is obtained by brominating the 2-position of the corresponding triphenylene and performing a cross-coupling reaction such as the Buchwald reaction (for example, see Non-Patent Document 4) with the bromo compound and the corresponding amine compound. Can be synthesized.

Specific examples of preferable compounds among the compounds having the triphenylene 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 a physical property value, a glass transition point (Tg) and a work function were measured. The glass transition point (Tg) is an index of stability in a thin film state, and the work function is an index of hole transportability.

The glass transition point (Tg) was 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.

As the structure of the organic EL device of the present invention, an organic EL device comprising an anode, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and a cathode sequentially on a substrate, and hole transport Examples thereof include those having an electron blocking layer between the light emitting layer and the light emitting layer, and those having a hole blocking layer between the light emitting layer and the hole transporting layer. 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. .
Each of the light emitting layer, the hole transport layer, and the electron transport layer may have a structure in which two or more layers are stacked.

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 the compound having a triphenylene ring structure represented by the general formula (1) of the present invention, a porphyrin compound represented by copper phthalocyanine, a starburst type triphenylamine Derivatives, materials such as 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 the compound having a triphenylene 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 ′, N′— Benzidine derivatives such as tetrabiphenylylbenzidine, 1,1-bis [4- (di-4-tolylamino) phenyl] cyclohexane (hereinafter abbreviated as TAPC), various triphenylamine trimers and tetramers, and carbazole 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. 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 the compound having the triphenylene ring structure represented by the general formula (1) of the present invention, 4,4 ′, 4 ″ -tri (N-carbazolyl) triphenyl Amine (hereinafter abbreviated as TCTA), 9,9-bis [4- (carbazol-9-yl) phenyl] fluorene, 1,3-bis (carbazol-9-yl) benzene (hereinafter abbreviated as mCP) , Carbazole derivatives such as 2,2-bis (4-carbazol-9-ylphenyl) adamantane (hereinafter abbreviated as Ad-Cz), 9- [4- (carbazol-9-yl) phenyl] -9- [ Compounds having an electron blocking action such as compounds having a triphenylsilyl group and a triarylamine structure typified by 4- (triphenylsilyl) phenyl] -9H-fluorene It 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. The light-emitting layer may be composed of a host material and a dopant material. In addition to the compound having a triphenylene ring structure represented by the general formula (1) of the present invention as the host material, in addition to the light-emitting material, 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 triphenylene 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 (biphenyl-4-yl)-(9,9-dimethyl-9H-fluoren-2-yl)-(triphenylene-2-yl) amine (Compound 4)>
In a reaction vessel purged with nitrogen, 12.3 g of (biphenyl-4-yl)-(9,9-dimethyl-9H-fluoren-2-yl) amine, 11.5 g of 2-bromotriphenylene, 3.92 g of sodium tert-butoxy Then, 180 ml of toluene was added, and nitrogen gas was aerated for 30 minutes while irradiating ultrasonic waves. 0.15 g of palladium acetate and 0.55 g of tris (tert-butyl) phosphine were added and heated, followed by stirring at 80 ° C. for 3 hours. After cooling to room temperature and adding 150 ml of toluene and 100 ml of water, the organic layer was collected by a liquid separation operation. The organic layer was dried over magnesium sulfate and concentrated under reduced pressure to obtain 23.8 g of a brown crude product. The crude product was dissolved in 400 ml of toluene and subjected to adsorption purification using 20.0 g of silica gel. After concentration under reduced pressure, crystallization using a mixed solvent of toluene / methanol and reflux washing using methanol were performed to give (biphenyl-4-yl)-(9,9-dimethyl-9H-fluorene-2 There was obtained 15.2 g (yield 76%) of a pale yellow powder of -yl)-(triphenylene-2-yl) amine (Compound 4).

The structure of the obtained pale yellow powder was identified using NMR.
^{The 1} H-NMR measurement results are shown in FIG.

^The following 33 hydrogen signals were detected by ¹ H-NMR (THF-d ₈ ). δ (ppm) = 8.98 (1H), 8.68 (4H), 8.50 (1H), 8.35 (1H), 7.72-7.58 (9H), 7.50-7. 39 (6H), 7.28 (5H), 7.19 (1H, 1.43 (6H).

<Synthesis of bis (9,9-dimethyl-9H-fluoren-2-yl)-(triphenylene-2-yl) amine (Compound 14)>
To a reaction vessel purged with nitrogen, 12.8 g of bis (9,9-dimethyl-9H-fluoren-2-yl) amine, 10.8 g of 2-bromotriphenylene, 3.67 g of tert-butoxy sodium, and 220 ml of toluene were added. Nitrogen gas was aerated for 30 minutes while irradiating with sound waves. 0.14 g of palladium acetate and 0.52 g of tris (tert-butyl) phosphine were added and heated, followed by stirring at 80 ° C. for 2 hours. The mixture was allowed to cool to room temperature, 100 ml of toluene and 100 ml of water were added, and then the organic layer was collected by a liquid separation operation. The organic layer was dried over magnesium sulfate and concentrated under reduced pressure to obtain 24.0 g of a brown crude product. The crude product was dissolved in 300 ml of toluene and subjected to adsorption purification using 10.0 g of silica gel. After concentrating under reduced pressure, crystallization using a mixed solvent of toluene / n-hexane, crystallization using a mixed solvent of toluene / methanol, and reflux washing using methanol are performed, whereby bis (9,9- 12.0 g (60% yield) of a pale yellow powder of dimethyl-9H-fluoren-2-yl)-(triphenylene-2-yl) amine (Compound 14) was obtained.

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

^The following 37 hydrogen signals were detected by ¹ H-NMR (THF-d ₈ ). δ (ppm) = 8.70 (2H), 8.64 (2H), 8.53 (1H), 8.32 (1H), 7.69 (4H), 7.59 (3H), 7.49 -7.45 (4H), 7.42 (2H), 7.28 (2H), 7.24-7.19 (4H), 1.42 (12H).

<Synthesis of (biphenyl-4-yl)-(4′-tert-butylbiphenyl-4-yl)-(triphenylene-2-yl) amine (Compound 33)>
In a reaction vessel purged with nitrogen, 12.5 g of (biphenyl-4-yl)-(4′-tert-butylbiphenyl-4-yl) amine, 11.2 g of 2-bromotriphenylene, 3.82 g of sodium tert-butoxy, toluene 200 ml was added, and nitrogen gas was aerated for 30 minutes while irradiating ultrasonic waves. 0.15 g of palladium acetate and 0.54 g of tris (tert-butyl) phosphine were added and heated, followed by stirring at 80 ° C. for 2 hours. The mixture was allowed to cool to room temperature, 150 ml of toluene and 50 ml of water were added, and then the organic layer was collected by a liquid separation operation. The organic layer was dried over magnesium sulfate and concentrated under reduced pressure to obtain 22.9 g of a brown crude product. The crude product was dissolved in 200 ml of toluene and subjected to adsorption purification using 20.0 g of silica gel. After concentration under reduced pressure, crystallization using a mixed solvent of tetrahydrofuran / n-hexane, crystallization using a mixed solvent of tetrahydrofuran / methanol, and reflux washing using methanol were performed to give (biphenyl-4-yl). )-(4′-tert-butylbiphenyl-4-yl)-(triphenylene-2-yl) amine (Compound 33) 14.7 g (yield 73%) of a pale yellow powder was obtained.

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

^The following 37 hydrogen signals were detected by ¹ H-NMR (THF-d ₈ ). δ (ppm) = 8.71 (2H), 8.65 (2H), 8.49 (1H), 8.38 (1H), 7.60 (11H), 7.52 (1H), 7.45 (3H), 7.40 (2H), 7.29 (5H), 1.35 (9H).

<Synthesis of (4′-tert-butylbiphenyl-4-yl)-(9,9-dimethyl-9H-fluoren-2-yl)-(triphenylene-2-yl) amine (Compound 35)>
Into a nitrogen-substituted reaction vessel, 13.0 g of (4′-tert-butylbiphenyl-4-yl)-(9,9-dimethyl-9H-fluoren-2-yl) amine, 10.5 g of 2-bromotriphenylene, tert -Butoxy sodium 3.58g and toluene 180ml were added, and nitrogen gas was ventilated for 30 minutes while irradiating ultrasonic waves. 0.14 g of palladium acetate and 0.50 g of tris-tert-butylphosphine were added and heated, and stirred at 80 ° C. for 2 hours. The mixture was allowed to cool to room temperature, 200 ml of toluene and 100 ml of water were added, and then the organic layer was collected by a liquid separation operation. The organic layer was dried over magnesium sulfate and concentrated under reduced pressure, followed by crystallization using a mixed solvent of tetrahydrofuran / methanol, recrystallization using toluene, and reflux washing using methanol. tert-Butylbiphenyl-4-yl)-(9,9-dimethyl-9H-fluoren-2-yl)-(triphenylene-2-yl) amine (Compound 35) white powder 11.3 g (yield 57%) )

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

^The following 41 hydrogen signals were detected by ¹ H-NMR (THF-d ₈ ). δ (ppm) = 8.67 (4H), 8.49 (1H), 8.34 (1H), 7.70 (2H), 7.59 (7H), 7.49-7.41 (6H) 7.29 (3H), 7.24 (1H), 7.18 (1H), 1.42 (6H), 1.34 (9H).

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).
Glass transition point
Inventive Example 1 Compound 129 ° C.
Inventive Example 2 Compound 146 ° C.
Compound of Invention Example 3 126 ° C.
Inventive Example 4 Compound 140 ° 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 Invention Example 1 5.56 eV
Inventive Example 2 compound 5.63 eV
Inventive Example 3 compound 5.48 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 this hole injection layer 3, the compound (compound 4) of Example 1 of the present invention was formed as a 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 1 (Compound 4) 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 1 of the present invention (Compound 4) 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 of 10 mA / cm ² was passed was 5.06 V for the compound of Example 1 of the present invention (Compound 4) versus 5.17 V for Compound 101. The voltage of the compound (Compound 4) of Example 1 of the present invention was greatly improved to 6.52 lm / W, compared with 5.49 lm / W of Compound 101 in terms of power efficiency.

As is clear from the above results, the organic EL device using the compound having a triphenylene ring structure of the present invention has improved luminous efficiency and power efficiency as compared with the known organic EL device using the compound 101. It was also found that a decrease in practical driving voltage can be achieved.

The compound having a triphenylene ring structure according to the present invention is excellent as a compound for an organic EL device because it has a high hole transport ability, is excellent in amorphous properties, and is stable in a thin film state. 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 (7)

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

(In the formula, Ar ₁ and Ar ₂ 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. Which may be bonded to each other through a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a nitrogen atom, and R ₁ , R ₂ and R ₃ may be the same as each other; May be different, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent, and a substituent. An optionally substituted cycloalkyl group having 5 to 10 carbon atoms, an optionally substituted linear or branched alkenyl group having 2 to 6 carbon atoms, and a substituent. A straight of 1 to 6 carbon atoms Or branched alkyloxy group, optionally substituted cycloalkyloxy group having 5 to 10 carbon atoms, substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aromatic heterocycle Di having a substituent selected from a group, a substituted or unsubstituted condensed polycyclic aromatic group, a substituted or unsubstituted aryloxy group, or an aromatic hydrocarbon group, an aromatic heterocyclic group, and a condensed polycyclic aromatic group Represents a substituted amino group, r ₁ , r ₂ and r ₃ may be the same or different from each other; r ₁ and r ₂ represent 0 or an integer of 1 to 4; and r ₃ represents an integer of 0 or 1 to 3 Here, when a plurality of R ₁ , R ₂ and R ₃ are bonded to the same benzene ring (when r ₁ , r ₂ or r ₃ is 2 or more), they may be the same or different from each other. It shall be good.) A compound having a triphenylene ring structure represented by the following general formula (2).

(In the formula, Ar ₁ and Ar ₂ 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. Which may be bonded to each other through a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a nitrogen atom, and R ₁ , R ₂ and R ₃ may be the same as each other; May be different, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent, and a substituent. An optionally substituted cycloalkyl group having 5 to 10 carbon atoms, an optionally substituted linear or branched alkenyl group having 2 to 6 carbon atoms, and a substituent. A straight of 1 to 6 carbon atoms Or branched alkyloxy group, optionally substituted cycloalkyloxy group having 5 to 10 carbon atoms, substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aromatic heterocycle Di having a substituent selected from a group, a substituted or unsubstituted condensed polycyclic aromatic group, a substituted or unsubstituted aryloxy group, or an aromatic hydrocarbon group, an aromatic heterocyclic group, and a condensed polycyclic aromatic group Represents a substituted amino group, r ₁ , r ₂ and r ₃ may be the same or different from each other; r ₁ and r ₂ represent 0 or an integer of 1 to 4; and r ₃ represents an integer of 0 or 1 to 3 Here, when a plurality of R ₁ , R ₂ and R ₃ are bonded to the same benzene ring (when r ₁ , r ₂ or r ₃ is 2 or more), they may be the same or different from each other. It shall be good.) In the organic electroluminescence device having at least one organic layer sandwiched between a pair of electrodes, the compound having a triphenylene ring structure according to claim 1 or 2 is used as a constituent material of at least one organic layer. An organic electroluminescence device characterized by comprising:   The organic electroluminescence device according to claim 3, wherein the organic layer is a hole transport layer.   4. The organic electroluminescence device according to claim 3, wherein the organic layer is an electron blocking layer.   The organic electroluminescence device according to claim 3, wherein the organic layer is a hole injection layer.   The organic electroluminescence device according to claim 3, wherein the organic layer is a light emitting layer.

Images