WO2018058494A1

WO2018058494A1 - Organic compound and electronic device comprising organic layer comprising organic compound

Info

Publication number: WO2018058494A1
Application number: PCT/CN2016/100992
Authority: WO
Inventors: Chong XING; Zhengming TANG; Shaoguang Feng; Robert Wright; David Dayton DEVORE; Minrong ZHU; Hong Yeop NA; Yan Luo; Yuchen Liu; Hua Ren; Jichang FENG; Sukrit MUKHOPADHYAY; Bruce M. Bell; Kenneth Kearns
Original assignee: Dow Global Technologies Llc; Rohm And Haas Electronic Materials Korea Ltd.
Priority date: 2016-09-30
Filing date: 2016-09-30
Publication date: 2018-04-05

Abstract

Organic compounds suitable for organic layers of electronic devices that have reduced driving voltage, increased luminous efficiency and increased power efficiency.

Description

ORGANIC COMPOUND AND ELECTRONIC DEVICE COMPRISING AN ORGANIC LAYER COMPRISING THE ORGANIC COMPOUND

FIELD OF THE INVENTION

The present invention relates to organic compounds, and an electronic device comprising an organic layer comprising the organic compounds.

INTRODUCTION

Organic light emitting diodes (OLEDs) are display devices that employ stacks of organic layers including electron transport layers (ETLs) and hole transport layers (HTLs) . OLEDs have drawn much attention in recent years as one of the most promising next-generation displays because of their many performance advantages including light weight, energy saving and high contrast.

There is still a desire to provide OLEDs with improved device performance including minimized power consumption, especially for battery-powered mobile applications.

SUMMARY OF THE INVENTION

The present invention provides organic compounds having a structure represented by Formula (1) :

Formula (1) ,

wherein R₁, R₂, R₃, and R₄ are each independently selected from the group consisting of hydrogen, deuterium ( “D” ) , a substituted or unsubstituted C₁-C₅₀ alkyl, a substituted or unsubstituted C₁-C₅₀ alkoxy, a substituted or unsubstituted C₁-C₅₀ alkoxycarbonyl, a substituted or unsubstituted C₆-C₆₀ aryl, a substituted or unsubstituted C₁-C₆₀ heteroaryl, a substituted or unsubstituted C₆-C₆₀ aryloxy, a substituted or unsubstituted C₆-C₅₀ arylthio, a halogen, a cyano, a hydroxyl, and a carbonyl；

R₅ is a substituted or unsubstituted C₁-C₃₀ alkyl, a substituted or unsubstituted C₃-C₅₀ cycloalkyl, a substituted or unsubstituted C₆-C₆₀ aryl, or a substituted or unsubstituted C₁-C₆₀ heteroaryl；

R₆ and R₇ are each independently selected from the group consisting of hydrogen, deuterium, a substituted or unsubstituted C₁-C₅₀ alkyl, a substituted or unsubstituted C₁-C₅₀ alkoxy, a substituted or unsubstituted C₁-C₅₀ alkoxycarbonyl, a substituted or unsubstituted C₆-C₆₀ aryl, a substituted or unsubstituted C₁-C₆₀ heteroaryl, a substituted or unsubstituted C₆-C₅₀ aryloxy, a substituted or unsubstituted C₆-C₅₀ arylthio, a halogen, a cyano, a hydroxyl, a carbonyl, and a substituted amino group having the structure of

wherein Ar₁ and Ar₂ are each independently selected from the group consisting of a substituted or unsubstituted C₆-C₆₀ aryl and a substituted or unsubstituted C₁-C₆₀ heteroaryl； with the proviso that at least one of R₆ and R₇ is the substituted amino group； and

X₁ and X₂ are each independently a chemical bond, or selected from the group consisting of a substituted or unsubstituted C₁-C₅₀ alkylene, a substituted or unsubstituted C₃-C₅₀ cycloalkylene, a substituted or unsubstituted C₆-C₆₀ arylene, and a substituted or unsubstituted C₁-C₆₀ heteroarylene； and X may form one or more fused rings with the adjacent phenyl ring.

The present invention further provides an electronic device comprising an organic layer comprising the organic compounds.

DETAILED DESCRIPTION OF THE INVENTION

The organic compounds of the present invention have the structure represented by Formula (1) :

Formula (1) ,

wherein R₁, R₂, R₃, and R₄ are each independently selected from the group consisting of hydrogen； deuterium ( “D” ) ； a substituted or unsubstituted C₁-C₅₀ alkyl, C₁-C₃₀ alkyl, C₁- C₂₀ alkyl, or C₁-C₁₀ alkyl； a substituted or unsubstituted C₁-C₅₀ alkoxy, C₁-C₃₀ alkoxy, C₁-C₂₀ alkoxy, or C₁-C₁₀ alkoxy； a substituted or unsubstituted C₁-C₅₀ alkoxycarbonyl, C₁-C₃₀ alkoxycarbonyl, C₁-C₂₀ alkoxycarbonyl, or C₁-C₁₀ alkoxycarbonyl； a substituted or unsubstituted C₆-C₆₀ aryl, C₆-C₃₀ aryl, C₆-C₂₀ aryl, or C₆-C₁₂ aryl； a substituted or unsubstituted C₁-C₆₀ heteroaryl, C₁-C₃₀ heteroaryl, C₂-C₂₀ heteroaryl, or C₄-C₁₂ heteroaryl； a substituted or unsubstituted C₆-C₆₀ aryloxy, C₆-C₃₀ aryloxy, C₆-C₂₀ aryloxy, or C₆-C₁₀ aryloxy； a substituted or unsubstituted C₆-C₅₀ arylthio, C₆-C₃₀ arylthio, C₆-C₂₀ arylthio, or C₆-C₁₀ arylthio； a halogen such as F, Cl, Br or I； a cyano； a hydroxyl； and a carbonyl. R₁ and R₂, R₂ and R₃, or R₃ and R₄ may respectively and independently form a 4-to 8-membered fused ring.

Preferably, R₁, R₂, R₃ and R₄ are each independently selected from hydrogen, a halogen, a substituted or unsubstituted C₁-C₃ alkyl, and a substituted or unsubstituted C₆-C₆₀ aryl. More preferably, R₁, R₂, R₃ and R₄ are each independently selected from hydrogen, F, methyl, phenyl, naphthyl, and biphenyl.

In some embodiments, at least two of R₁ through R₄ are hydrogen. Preferably, all R₁ through R₄ are hydrogen.

R₅ is a substituted or unsubstituted C₁-C₃₀ alkyl, C₁-C₂₀ alkyl, C₁-C₁₀ alkyl, C₁-C₅ alkyl, or C₁-C₃ alkyl； a substituted or unsubstituted C₃-C₅₀ cycloalkyl, C₄-C₃₀ cycloalkyl, C₄-C₂₀ cycloalkyl, or C₄-C₁₂ cycloalkyl； a substituted or unsubstituted C₆-C₆₀ aryl, C₆-C₃₀ aryl, C₆-C₂₀ aryl, or C₆-C₁₂ aryl； or a substituted or unsubstituted C₁-C₆₀ heteroaryl, C₁-C₃₀ heteroaryl, C₂-C₂₀ heteroaryl, or C₄-C₁₂ heteroaryl. Preferably, R₅ is selected from -CH₃ , -CH₂CH₃,

R₆ and R₇ are each independently selected from the group consisting of hydrogen； deuterium； a substituted or unsubstituted C₁-C₅₀ alkyl, C₁-C₃₀ alkyl, C₁-C₂₀ alkyl, or C₁-C₁₀ alkyl； a substituted or unsubstituted C₁-C₅₀ alkoxy, C₁-C₃₀ alkoxy, C₁-C₂₀ alkoxy, or C₁-C₁₀ alkoxy； a substituted or unsubstituted C₁-C₅₀ alkoxycarbonyl, C₁-C₃₀ alkoxycarbonyl, C₁-C₂₀ alkoxycarbonyl, or C₁-C₁₀ alkoxycarbonyl； a substituted or unsubstituted C₆-C₆₀ aryl, C₆-C₃₀ aryl, C₆-C₂₀ aryl, or C₆-C₁₂ aryl； a substituted or unsubstituted C₁-C₆₀ heteroaryl, C₁-C₃₀ heteroaryl, C₂-C₂₀ heteroaryl, or C₄-C₁₂ heteroaryl； a substituted or unsubstituted C₆-C₆₀ aryloxy, C₆-C₃₀ aryloxy, C₆-C₂₀ aryloxy, or C₆-C₁₀ aryloxy； a substituted or unsubstituted C₆-C₅₀ arylthio, C₆-C₃₀ arylthio, C₆-C₂₀ arylthio, or C₆-C₁₀ arylthio； a halogen such as F, Cl, Br or I； a cyano； a hydroxyl； a carbonyl； and a substituted amino group having the structure of

with the proviso that at least one of R₆ and R₇ is the substituted amino group. Ar₁ and Ar₂ are each independently selected from the group consisting of a substituted or unsubstituted C₆-C₆₀ aryl, C₆-C₃₀ aryl, C₆-C₂₀ aryl, or C₆-C₁₅ aryl； and a substituted or unsubstituted C₁-C₆₀ heteroaryl, C₁-C₃₀ heteroaryl, C₂-C₂₀ heteroaryl, or C₄-C₁₂ heteroaryl. Preferably, Ar₁ and Ar₂ are each independently a substituted or unsubstituted C₆-C₆₀ aryl. More preferably, Ar₁ and Ar₂ are each independently a substituted or unsubstituted C₁₂-C₃₀ aryl.

In some embodiments, only one of R₆ and R₇ is the substituted amino group. Preferably, one of R₆ and R₇ is the substituted amino group, and the other one of R₆ and R₇ is selected from hydrogen, a halogen, or a substituted or unsubstituted C₆-C₆₀ aryl.

In some embodiments, the substituted amino group is selected from the following structures represented by Formula (a) through Formula (c) :

Formula (a) ,

Formula (b) , and

Formula (c) ,

wherein Ar₃ and Ar₄ are each independently an unsubstituted C₆-C₆₀ aryl, Ar₅ through Ar₇ are each independently an unsubstituted C₆-C₄₀ aryl, and Ar₈ through Ar₁₁ are each independently an unsubstituted C₆-C₃₀ aryl； and L₁ through L₃ are each independently selected from the group consisting of a substituted or unsubstituted C₆-C₆₀ arylene and a substituted or unsubstituted C₁-C₆₀ heteroarylene. Preferably, Ar₃ through Ar₁₁ may be each independently an unsubstituted C₆-C₃₀ aryl, C₆-C₂₀ aryl, C₆-C₁₅ aryl, or C₆-C₁₂ aryl.

Suitable examples of the substituted amino groups comprise the following structures (1) through (6) :

X₁ and X₂ may be the same or different.

X₁ and X₂ are each independently a chemical bond, or selected from the group consisting of a substituted or unsubstituted C₁-C₅₀ alkylene, a substituted or unsubstituted C₃-C₅₀ cycloalkylene, a substituted or unsubstituted C₆-C₆₀ arylene, and a substituted or unsubstituted C₁-C₆₀ heteroarylene.

In the embodiments where X₁ or X₂ is a chemical bond, it means that R₆ or R₇ is directly linked to its adjacent phenyl ring through X₁ or X₂.

In some embodiments, X_l or X₂ may form one or more fused rings with the adjacent phenyl ring.

Suitable examples of X_l or X₂ comprise

Preferably, the organic compounds of the present invention have the structure represented by Formula (2) or (3) :

Formula (2) , or

Formula (3) ,

wherein X_l and X₂, Ar₁ and Ar₂, and R₁ through R₅, are as previously defined with reference to Formula (1) .

Suitable examples of the organic compounds are selected from the following structures (7) through (22) :

The organic compounds of the present invention may have a molecular weight of 500 g/mole or more, 600 g/mole or more, or even 700 g/mole or more, and at the same time, 1,000 g/mole or less, 900 g/mole or less, or even 800 g/mole or less.

The organic compounds of the present invention may have a glass transition temperature (Tg) of 110 ℃ or higher, 130 ℃ or higher, or 150 ℃ or higher, and at the same time, 250 ℃ or lower, 220 ℃ or lower, or even 200 ℃ or lower, as measured according to the test method described in the Examples section below.

The organic compounds of the present invention may have a decomposition temperature (Td, 5％weight loss) of 300 ℃ or higher, 350 ℃ or higher, or 400 ℃ or higher, and at the same time, 650 ℃ or lower, 600 ℃ or lower, or even 550 ℃ or lower, as measured according to the test method described in the Examples section below.

The organic compounds of the present invention may be prepared as shown in Scheme 1 below. Aldehyde derivatives were first reacted through Stetter reaction with unsaturated ketone derivatives to produce Structure A product, which were then condensed with amines under the catalysis of p-toluenesulfonic acid to produce Structure B product. Under the catalytic condition of palladium acetate and ligand, Structure B product could be cyclized to produce Structure C products having a fused pyrrole ring. Structure C products were then treated with N-Iodosuccinimide (NIS) , followed by the coupling reaction with phenylboronic acid to produce Structure D products. After a final Buchwald-Hartwig reaction, Formula (1) of the present invention could be obtained.

SCHEME 1

The organic compounds of the present invention may be used in organic layers including hole transport layers (HTL) , electron transport layers (ETL) , hole injection layers (HIL) , charge blocking layers, charge generation layers, and emissive layers (EML) in electronic devices. Preferably, the organic layer is a hole transport layer or a hole injection layer. The term “charge blocking layer” herein refers to certain layers of structures blocking charge transfer to improve efficiency. The term “charge generation layer” herein refers to certain layers of structures which can generate charges.

Electronic devices are devices depending on the principles of electronics and using the manipulation of electron flow for its operation. The organic compounds of the present invention may be used in electronic devices including organic photovoltaic cells, organic field effect transistors (OFETs) , and light emitting devices. Light emitting devices are electronic devices emitting lights when electrical currents were applied across two electrodes in the devices.

The electronic device of the present invention may comprise an anode, a cathode, and at least one organic layer interposed between the anode and the cathode. At least one of the organic layers comprises at least one of the organic compounds of the present invention. The organic layer can be a charge transfer layer that can transport charge carrying moieties, either holes or electrons. The organic layer may be a hole transport layer, an emissive layer, an electron transport layer, or a hole injection layer. Preferably, the organic layer is a hole transport layer or a hole injection layer. In addition to the organic compounds of the present invention, the organic layer may comprise one or more “dopants” . Dopants are impurities deliberately added in small amounts to a pure substance (i.e., a “host” ) to alter its properties such as conductivity and emitting property. It has the effect of shifting the Fermi level of the original material (i.e., the “host” ) , which results in a material with predominantly negative (n-type) or positive (p-type) charge carriers depending on the dopant variety. The organic layer comprising the organic compounds of the present invention may be prepared by evaporative vacuum deposition or solution process such as spin coating, slot die coating and ink-jet printing. The organic compounds of the present invention may be a part of polymer resin of Mn higher than 6,000 Dalton. The polymer resin can be synthesized by a mixture of the organic compounds of the present invention, where the concentration of individual monomers can vary from 0.1％to 99.9％. The polymer resin can be deposited using spin coating, slot die coating or ink-jet printing.

The term “aryl, ” as described herein, refers to an organic radical derived from aromatic hydrocarbon by the removal of one hydrogen atom therefrom. An aryl group may be a monocyclic and/or fused ring system each ring of which suitably contains from 4 to 6, preferably from 5 or 6 atoms. Structures wherein two or more aryl groups are combined through single bond (s) are also comprised. Examples of aryls comprise phenyl, naphthyl, biphenyl, anthryl, indenyl, fluorenyl, benzofluorenyl, phenanthryl, triphenylenyl, pyrenyl, perylenyl, chrysenyl, naphtacenyl, fluoranthenyl and the like. The naphthyl may be 1-naphthyl or 2-naphthyl. The anthryl may be 1-anthryl, 2-anthryl or 9-anthryl. The fluorenyl may be any one of 1-fluorenyl, 2-fluorenyl, 3-fluorenyl, 4-fluorenyl and 9-fluorenyl.

The term “substituted aryl, ” as described herein, refers to an aryl in which at least one hydrogen atom is substituted with a heteroatom or a chemical group containing at least one heteroatom. Heteroatoms comprise O, N, P and S. The chemical group containing at least one heteroatom herein comprise OR’ , NR’ ₂, PR’ ₂, P (＝O) R’ ₂, and SiR’ ₃； wherein each R’ is hydrogen or a C₁-C₃₀ hydrocarbyl.

The term “heteroaryl, ” as described herein, refers to an aryl group, in which at least one carbon atom or CH group or CH₂ group is substituted with a heteroatom (for example, B, N, O, S, P (＝O) , Si and P) or a chemical group containing at least one heteroatom. The heteroaryl may be a 5-or 6-membered monocyclic heteroaryl or a polycyclic heteroaryl which is fused with one or more benzene ring (s) , and may be partially saturated. The structures having one or more heteroaryl group (s) bonded through a single bond are also comprised. The heteroaryl groups comprise divalent aryl groups of which the heteroatoms are oxidized or quarternized to form N-oxides, quaternary salts, or the like. Specific examples comprise monocyclic heteroaryl groups, such as furyl, thiophenyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl, triazolyl, tetrazolyl, furazanyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl； polycyclic heteroaryl groups, such as benzofuranyl, fluoreno [4, 3-b] benzofuranyl, benzothiophenyl, fluoreno [4, 3-b] benzothiophenyl, isobenzofuranyl, benzimidazolyl, benzothiazolyl, benzisothiazolyl, benzisoxazolyl, benzoxazolyl, isoindolyl, indolyl, indazolyl, benzothiadiazolyl, quinolyl, isoquinolyl, cinnolinyl, quinazolinyl, quinoxalinyl, carbazolyl, phenanthridinyl and benzodioxolyl； and corresponding N-oxides (for example, pyridyl N-oxide, quinolyl N-oxide) and quaternary salts thereof.

The term “substituted heteroaryl, ” as described herein, refers to a heteroaryl in which at least one hydrogen atom is substituted with a heteroatom or a chemical group containing at least one heteroatom. Heteroatoms comprise O, N, P and S. The chemical group containing at least one heteroatom comprise OR’ , NR’ ₂, PR’ ₂, P (＝O) R’ ₂, and SiR’ ₃； wherein each R’ is hydrogen or a C₁-C₃₀ hydrocarbyl.

The term “hydrocarbyl, ” as described herein, refers to a chemical group containing only hydrogen and carbon atoms.

“Alkyl, ” and other substituents containing “alkyl” moiety, comprises both linear and branched species. Examples of alkyls comprise methyl, ethyl, propyl, iso-propyl, butyl, iso-butyl, tert-butyl, pentyl, and hexyl.

The term “substituted alkyl, ” as described herein, refers to an alkyl in which at least one hydrogen atom is substituted with a heteroatom or a chemical group containing at least one heteroatom. Heteroatoms comprise O, N, P and S. The chemical group containing at least one heteroatom herein comprise OR’ , NR’ ₂, PR’ ₂, P (＝O) R’ ₂, and SiR’ ₃； wherein each R’ is hydrogen or a C₁-C₃₀ hydrocarbyl.

The term “cycloalkyl, ” as described herein, refers to a monocyclic hydrocarbon and a polycyclic hydrocarbon such as substituted or unsubstituted adamantyl, and substituted or unsubstituted C₇-C₃₀ bicycloalkyl.

EXAMPLES

The following examples illustrate embodiments of the present invention. All parts and percentages are by weight unless otherwise indicated.

Materials and NMR information

Commercially available materials purchased from Sinopharm Chemical Reagent Co., Ltd. (SCRC) or Energy Chemicals were used as received. Proton nuclear magnetic resonance (¹H NMR) spectra were recorded on Bruker AVANCE III (400 MHz) spectrometer. Chemical shifts were recorded in parts per million (ppm) relative to tetramethylsilane (0.00) . ¹H NMR splitting patterns were designated as singlet (s) , doublet (d) , triplet (t) , quartet (q) , doublet of doublets (dd) , multiplet (m) , and etc. All first-order splitting patterns were assigned on the basis of the appearance of the multiplet. Splitting patterns that could not be easily interpreted are designated as multiplet (m) or broad (br) .

Modeling

All computations utilized the Gaussian 09 program as described in Gaussian 09, Revision A. 02, Frisch, M.J. et al., Gaussian, Inc., Wallingford CT, 2009. The calculations were performed with the hybrid Density Functional Theory (DFT) method, Becke, 3-parameter, Lee-Yang-Parr (B3LYP) , as described in Becke, A.D. J. Chem. Phys. 1993, 98, 5648； Lee, C. et al., Phys. Rev B 1988, 37, 785； and Miehlich, B. et al. Chem. Phys. Lett. 1989, 157, 200； and the 6-31G* (5d) basis set as described in Ditchfield, R. et al., J. Chem. Phys. 1971, 54, 724； Hehre, W.J. et al., J. Chem. Phys. 1972, 56, 2257； and Gordon, M.S. Chem. Phys. Lett. 1980, 76, 163. The singlet state calculations use the closed shell approximation, and the triplet state calculations use the open shell approximation. All values are quoted in electron volts (eV) . The Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) values are determined from the orbital energies of the optimized geometry of the singlet ground state. The triplet energies are determined as the difference between the total energy of the optimized triplet state and the optimized singlet state. A procedure, as described in Lin, B. C et al., J. Phys. Chem. A 2003, 107, 5241-5251, is applied to calculate the reorganization energy of each molecule, with which as the indicator of electron and hole mobility.

Differential scanning calorimetry (DSC)

DSC measurements were carried out on Q2000 differential scanning calorimeter of TA Instruments at a scan rate of 10 ℃/min under N₂ atmosphere for all cycles. Each sample (about 7-10 mg) was scanned from room temperature to 300 ℃ (first heating scan) , cooled to -60 ℃, and then reheated to 300 ℃ (second heating scan) . Tg was measured on the second heating scan. Data analysis was performed using Universal Analysis 2000 software of TA Instruments. The Tg value was calculated using an “onset-at-inflection” methodology.

Thermo gravimetric analysis (TGA)

TGA measurements were carried out on TGA-Q500 thermo gravimetric analyzer of TA Instruments under N₂ atmosphere. Each sample (about 7-10 mg) was weighed in a platinum standard plate and loaded into the instrument. Each sample was first heated to 60 ℃and equilibrated for 30 minutes to remove solvent residues in the sample. Then the sample was cooled to 30 ℃. The temperature was ramped from 30 ℃ to 600 ℃ with 10 ℃/min rate and the weight change was recorded to determine the decomposition temperature (Td) of the sample. The temperature-weight ％ (T-Wt ％) curve was obtained by TGA scan. The temperature at the 5 ％weight loss was determined as Td.

Liquid Chromatography-Mass Spectrometry (LC-MS)

Each sample was dissolved in tetrahydrofuran (THF) at around 0.6 mg/mL. 5 μL sample solution was injected on an Agilent 1220 HPLC/G6224A time-of-flight mass spectrometer. The following analysis conditions were used:

Column: 4.6 x 150 mm, 3.5 μm ZORBAX Eclipse Plus C18； column temperature: 40 ℃； Mobile phase: THF/deioned (DI) water ＝ 65/35 volume ratio (Isocratic method) ； Flow rate: 1.0 mL/min； and

MS conditions: Capillary Voltage: 3500 kV (Pos) ； Mode: Pos； Scan: 100-2000 amu； Rate: 1 s/scan； and Desolvation temperature: 300 ℃.

High Performance Liquid Chromatography (HPLC)

Each sample was dissolved in THF at around 0.6 mg/mL. The sample solution was at last filtrated through a 0.45 μm syringe filter and 5 μL of the filtrate was injected to HPLC system. The following analysis conditions were used:

Injection volume: 5 μL； Instrument: Agilent 1200 HPLC； Column: 4.6 x 150mm, 3.5μm ZORBAX Eclipse Plus C18； Column temperature: 40 ℃； Detector: DAD＝250, 280, 350 nm； Mobile Phase: THF/DI water ＝ 65/35 volume ratio (Isocratic method) ； and Flow rate: 1 mL/min.

Example 1: Synthesis Route of Organic Compound Structures 9 and 10

Synthesis of organic compound Structure 9

Structure A1: 3-Ethyl-5- (2-hydroxyethyl) -4-methylthiazol-3-ium bromide catalyst (504 mg, 2 mmol) and potassium carbonate (276 mg, 2 mmol) were added at room temperature to a solution of benzaldehyde (1.27 g, 12 mmol) and (E) -3- (2-bromo-4-chlorophenyl) -1-phenylprop-2-en-1-one (3.22 g, 10 mmol) in THF (20 mL) . The reaction mixture was stirred in N₂ atmosphere at 60 ℃ for 2 days to produce Structure A1 product.

Structure B1: Thin Layer Chromatography (TLC) was used to monitor the reaction. Solvent was removed by rotation evaporator right after the completion of the reaction. Aniline (1.86 g, 20 mmol) and p-toluenesulfonic acid (5.71 g, 30 mmol) were added into the reaction mixture of Structure A1 together with 50 mL ethanol and 4A molecular sieves. The mixture was stirred at reflux for 24 h. After that, DI water was added and the precipitate was filtered out. The precipitate could be further purified by column chromatography to give the pure product. ¹H NMR (400 MHz, CDCl₃, ppm) : 7.60 (d, 1H, J ＝ 2.0 Hz) , 7.15-7.25 (m, 6H) , 7.00-7.11 (m, 9H) , 6.85 (d, 1H, J ＝ 8.0 Hz) , 6.64 (s, 1H) . LC-MS-ESI (m/z) : calcd for C₂₈H₂₀BrClN: 483.04, found (M+H) ⁺: 484.0482.

Structure C1: Potassium carbonate (5.52 g, 40 mmol) was added to a mixture of Structure B1 (9.6g, 20 mmol) , palladium acetate (224 mg, 1 mmol) and tricyclohexylphosphine tetrafluoroborate (740 mg, 2 mmol) in dimethylacetamide (DMA) (50 mL) . The reaction mixture was stirred at reflux overnight under N₂ atmosphere. TLC was used to monitor the reaction. After completion of the reaction, DI water was added and the precipitate was filtered out. The precipitate was purified directly by column chromatography to give pure product of Structure C1. ¹H NMR (400 MHz, CDCl₃, ppm) : 8.61-8.64 (m, 2H) , 8.22 (d, 1H, J ＝ 10.0 Hz) , 7.59 (d, 1H, J ＝ 6.8 Hz) , 7.40-7.50 (m, 6H) , 7.16-7.26 (m, 8H) . LC-MS-ESI (m/z) : calcd for C₂₈H₁₈NCl: 403.11, found (M+H) ⁺: 404.1211.

Structure D1: N-Iodosuccinimide (NIS) (2.36 g, 10.5 mmol) was added to a solution of structure C1 (4.04 g, 10 mmol) in dichloromethane (20 mL) at 0 ℃. The reaction mixture was stirred at room temperature for 2 hours. TLC was used to monitor the reaction. After completion of the reaction, DI water was added to quench the reaction and the crude product G1 was filtered to be used directly in the next step without any purification. To a solution of Compound G1 (1.06 g, 2 mmol) and phenylboric acid (0.29 g, 2.4 mmol) in toluene (20 mL) was added palladium acetate (22.4 mg, 0.1 mmol) , tricyclohexylphosphine tetrafluoroborate (74 mg, 0.2 mmol) and potassium phosphate (424 mg, 4 mmol) . The reaction mixture was stirred at 60 ℃ in N₂ atmosphere for overnight. TLC was used to monitor the reaction. After completion of the reaction, DI water was added and the precipitate was filtered out. The precipitate was further purified by column chromatography to give the pure product. ¹H NMR (400 MHz, CDCl3, ppm) : 8.61-8.63 (m, 2H) , 7.75 (d, 1H, J ＝ 8.8 Hz) , 7.30-7.50 (m, 12H) , 7.15-7.25 (m, 2H) , 6.93-7.10 (m, 5H) . LC-MS-ESI (m/z) : calcd for C₃₄H₂₂NCl: 479.14, found (M+H) ⁺: 480.1533.

Structure 9: Palladium acetate (89.6 mg, 0.4 mmol) , tricyclohexylphosphine tetrafluoroborate (296 mg, 0.8 mmol) and sodium tert-butoxide (1.08 g, 11.2 mmol) were added to a solution of structure D1 (3.84 g, 8 mmol) and N- ( [1, 1'-biphenyl] -4-yl) -9, 9-dimethyl-9H-fluoren-2-amine (3.18 g, 8.8 mmol) in toluene (50 mL) . The reaction mixture was stirred at 100 ℃ in N₂ atmosphere for overnight. TLC was used to monitor the reaction. After completion of the reaction, DI water was added and the precipitate was filtered out. The precipitate was further purified by column chromatography to give the pure product. Repeated column chromatography or recrystallization was applied to further improve the purity to >99.5％. ¹H NMR (400 MHz, CDCl₃, ppm) : 8.40 (d, 1H, J ＝ 8.4 Hz) , 7.76 (d, 1H, J ＝ 8.8 Hz) , 7.26-7.45 (m, 29H) , 6.95-7.10 (m, 7H) , 1.41 (s, 6H) . LC-MS-ESI (m/z) : calcd for C₆₁H₄₄N₂: 804.35, found (M+H) ⁺: 805.3587.

Synthesis of organic compound Structure 10

Structure A2: 3-Ethyl-5- (2-hydroxyethyl) -4-methylthiazol-3-ium bromide catalyst (504 mg 2 mmol) and potassium carbonate (276 mg, 2 mmol) were added at room temperature to a solution of benzaldehyde (1.27 g, 12 mmol) and (E) -3- (2-bromo-4-chlorophenyl) -1-phenylprop-2-en-1-one (3.22 g, 10 mmol) in THF (20 mL) . The reaction mixture was stirred in N₂ atmosphere at 60 ℃ for 2 days to produce Structure A2 product.

Structure B2: TLC was used to monitor the reaction. After completion of the reaction, solvent was removed. Methylamine (1.55 g, 50 mmol) and p-toluenesulfonic acid (5.71 g, 30 mmol) were added into the reaction mixture of Structure A2 together with 50 mL ethanol and 4A molecular sieves. The mixture was stirred at reflux for 24 h. After that, DI water was added and the precipitate was filtered out. The precipitate was further purified by column chromatography to give the pure product. ¹H NMR (400 MHz, CDCl₃, ppm) : 7.57 (d, 1H, J ＝2.0 Hz) , 7.52-7.54 (m, 2H) , 7.43 (t, 2H) , 7.20-7.34 (m, 6H) , 7.06 (dd, 1H, J ＝ 2.4, 2.4 Hz) , 6.98 (d, 1H, J ＝ 8.4 Hz) , 6.45 (s, 1H) , 3.56 (s, 3H) . LC-MS-ESI (m/z) : calcd for C₂₃H₁₇BrClN: 421.02, found (M+H) ⁺: 422.0263.

Structure C2: Potassium carbonate (5.52 g, 40 mmol) was added to a mixture of structure B2 (8.44 g, 20 mmol) , palladium acetate (224 mg, 1 mmol) and tricyclohexylphosphine tetrafluoroborate (740 mg, 2 mmol) in DMA (50 mL) . The reaction mixture was stirred at reflux overnight under N₂ atmosphere. TLC was used to monitor the reaction. After completion of the reaction, DI water was added and the precipitate was filtered out. The precipitate was further purified by column chromatography to give the pure product. ¹H NMR (400 MHz, CDCl₃, ppm) : 8.70 (d, 1H, J ＝ 8.0 Hz) , 8.62 (d, 1H, J ＝ 2.0 Hz) , 8.54 (d, 1H, J ＝ 8.4 Hz) , 8.16 (d, 1H, J ＝ 8.8 Hz) , 7.64-7.68 (m, 1H) , 7.50-7.60 (m, 6H) , 7.41-7.46 (m, 1H) , 7.07 (s, 1H) , 4.21 (s, 3H) . LC-MS-ESI (m/z) : calcd for C₂₃H₁₆NCl: 341.10, found (M+H) ⁺: 342.1081

Structure D2: NIS (2.362 g, 10.5 mmol) was added to a solution of structure C2 (3.42 g, 10 mmol) in DCM (20 mL) at 0 ℃. The reaction mixture was stirred at room temperature for 2 hours. TLC was used to monitor the reaction. After completion of the reaction, DI water was added to quench the reaction and the crude product G2 was filtered to be used directly in the next step without any purification. To a solution of Compound G2 (0.93 g, 2 mmol) and phenylboric acid (0.29 g, 2.4 mmol) in toluene (20 mL) was added palladium acetate (22.4 mg, 0.1 mmol) , tricyclohexylphosphine tetrafluoroborate (74 mg, 0.2 mmol) and potassium phosphate (424 mg, 4 mmol) . The reaction mixture was stirred at 60 ℃ in N₂ atmosphere for overnight. TLC was used to monitor the reaction. After completion of the reaction, DI water was added and the precipitate was filtered out. The precipitate was further purified by column chromatography to give the pure product. ¹H NMR (400 MHz, CDCl₃, ppm) : 8.70 (d, 1H, J ＝8.4 Hz) , 8.58-8.62 (m, 2H) , 7.64-7.70 (m, 2H) , 7.55-7.62 (m, 1H) , 7.24-7.35 (m, 10H) , 7.20 (d, 1H, J ＝ 9.2 Hz) , 4.14 (s, 3H) . LC-MS-ESI (m/z) : calcd for C₂₉H₂₁NCl: 418.139, found (M+H) ⁺: 418.1832.

Structure 10: Palladium acetate (89.6 mg, 0.4 mmol) , tricyclohexylphosphine tetrafluoroborate (296 mg, 0.8 mmol) and sodium tert-butoxide (1.08 g, 11.2 mmol) were added to a solution of Structure D2 (3.34 g, 8 mmol) and N- ( [1, 1'-biphenyl] -4-yl) -9, 9-dimethyl-9H-fluoren-2-amine (3.18 g, 8.8 mmol) in toluene (50 mL) . The reaction mixture was stirred at 100 ℃ in N₂ atmosphere for overnight. TLC was used to monitor the reaction. After completion of the reaction, DI water was added and the precipitate was filtered out. The precipitate was further purified by column chromatography to give the pure product. Repeated column chromatography or to recrystallization was applied to further improve the purity to >99.5％. ¹H NMR (400 MHz, CDCl₃, ppm) : 8.50 (br, 1H) , 8.42 (d, 1H, J ＝ 8.4 Hz) , 8.15-8.62 (m, 31H) , 4.37-4.44 (br, 3H) , 1.33 (s, 6H) . LC-MS-ESI (m/z) : calcd for C56H₄₂N₂: 743.33, found (M+H) ⁺: 743.2-743.4.

Thermal property of organic compound Structures 9 and 10

Thermal properties of organic compounds Structures 9 and 10 were analyzed by DSC and TGA. As shown in Table 1, organic compound Structure 9 had a Tg of 164.5 ℃ and a Td of 416.2 ℃ and organic compound Structure 10 had a Tg of 161.4 ℃ and a Td of 402.7℃.

Table 1

Sample Name	Td (℃)	Tg (℃)
Structure 9	416.2	164.5
Structure 10	161.4	402.7

Example 2: OLED Device Fabrication

An OLED device containing organic compound Structure 10 as the hole transport layer was fabricated by thermally depositing organic layers, from bottom to top, electron injection layer (EIL) , electron transport layer (ETL) , emitting material layer (EML) , hole transport layer (HTL) , and hole injection layer (HIL) , onto an indium tin oxide (ITO) coated glass substrate that served as an anode, and topped with an aluminum cathode. Thermal deposition was conducted by chemical vapor deposition in a vacuum chamber with a base pressure of <10^-7 torr. The deposition rates of organic layers were maintained at 0.1-0.05 nm/s. The aluminum cathode was deposited at 0.5 nm/s. The active area of the OLED device was “3 mm x 3 mm. ” Organic materials used in organic layers were all purified by sublimation before deposition, and were placed inside the vacuum chamber until it reached 10^-6 torr. To evaporate each material, a controlled current was applied between the anode and the cathode to raise the temperature to keep the constant evaporation rate of 1A/s for each organic material.

Material and thickness of each organic layer were shown in Table 2.

A comparative OLED device containing N4, N4'-di (naphthalen-1-yl) -N4, N4'-diphenyl-[1, 1'-biphenyl] -4, 4'-diamine (NPB) as the hole transport layer was prepared with the similar procedure described above.

Table 2

The current density-voltage-luminance (J-V-L) characterizations for the OLED devices were performed with a KEITHLEY 2635A-SYS Single-channel System Source Meter and a MINOLTA CS-100A Chroma Meter.

As shown in Table 3, Inventive OLED Device had higher luminous and power efficiencies at a lower driving voltage compared to those of Comparative Device.

Table 3

Claims

An organic compound having a structure represented by Formula (1) :

wherein R₁, R₂, R₃, and R₄ are each independently selected from the group consisting of hydrogen, deuterium, a substituted or unsubstituted C₁-C₅₀ alkyl, a substituted or unsubstituted C₁-C₅₀ alkoxy, a substituted or unsubstituted C₁-C₅₀ alkoxycarbonyl, a substituted or unsubstituted C₆-C₆₀ aryl, a substituted or unsubstituted C₁-C₆₀ heteroaryl, a substituted or unsubstituted C₆-C₆₀ aryloxy, a substituted or unsubstituted C₆-C₅₀ arylthio, a halogen, a cyano, a hydroxyl, and a carbonyl；

R₅ is a substituted or unsubstituted C₁-C₃₀ alkyl； a substituted or unsubstituted C₃-C₅₀ cycloalkyl； a substituted or unsubstituted C₆-C₆₀ aryl； or a substituted or unsubstituted C₁-C₆₀ heteroaryl；

R₆ and R₇ are each independently selected from the group consisting of hydrogen, deuterium, a substituted or unsubstituted C₁-C₅₀ alkyl, a substituted or unsubstituted C₁-C₅₀ alkoxy, a substituted or unsubstituted C₁-C₅₀ alkoxycarbonyl, a substituted or unsubstituted C₆-C₆₀ aryl, a substituted or unsubstituted C₁-C₆₀ heteroaryl, a substituted or unsubstituted C₆-C₆₀ aryloxy, a substituted or unsubstituted C₆-C₅₀ arylthio, a halogen, a cyano, a hydroxyl, a carbonyl, and a substituted amino group having the structure of
wherein Ar₁ and Ar₂ are each independently selected from the group consisting of a substituted or unsubstituted C₆-C₆₀ aryl, and a substituted or unsubstituted C₁-C₆₀ heteroaryl； with the proviso that at least one of R₆ and R₇ is the substituted amino group； and

X₁ and X₂ are each independently a chemical bond, or selected from the group consisting of a substituted or unsubstituted C₁-C₅₀ alkylene, a substituted or unsubstituted C₃-C₅₀ cycloalkylene, a substituted or unsubstituted C₆-C₆₀ arylene, and a substituted or unsubstituted C₁-C₆₀ heteroarylene.
The organic compound of Claim 1, wherein R₁ and R₂, R₂ and R₃, or R₃ and R₄ may respectively and independently form a 4- to 8-membered fused ring.
The organic compound of Claim 1, wherein R₁, R₂, R₃ and R₄ are each independently selected from hydrogen, F, methyl, phenyl, naphthyl, and biphenyl.
The organic compound of Claim 1, wherein R₁ through R₄ are all hydrogen.
The organic compound of Claim 1, wherein R₅ is selected from -CH₃, -CH₂CH₃,
The organic compound of Claim 1, wherein one of R₆ and R₇ is the substituted amino group, and the other one of R₆ and R₇ is selected from hydrogen, a halogen, or a substituted or unsubstituted C₆-C₆₀ aryl.
The organic compound of Claim 1, wherein the substituted amino group is selected from the following structures represented by Formula (a) through Formula (c) :

wherein Ar₃ and Ar₄ are each independently an unsubstituted C₆-C₆₀ aryl, Ar₅ through Ar₇ are each independently an unsubstituted C₆-C₄₀ aryl, and Ar₈ through Ar₁₁ are each independently an unsubstituted C₆-C₃₀ aryl； and L₁ through L₃ are each independently selected from a substituted or unsubstituted C₆-C₆₀ arylene, and a substituted or unsubstituted C₁-C₆₀ heteroarylene.
The organic compound of Claim 7, wherein Ar₃ through Ar₁₁ may be each independently an unsubstituted C₆-C₃₀ aryl.
The organic compound of Claim 1, wherein the substituted amino groups comprise the following structures (1) through (6) :
The organic compound of Claim 1, wherein X_l or X₂ comprise
The organic compound of Claim 1, wherein X₁ or X₂ may form one or more fused rings with the adjacent phenyl ring.
The organic compound of Claim 1, wherein the organic compounds of the present invention have the structure represented by Formula (2) or (3) :

wherein R₁, R₂, R₃, and R₄ are each independently selected from the group consisting of hydrogen, deuterium, a substituted or unsubstituted C₁-C₅₀ alkyl, a substituted or unsubstituted C₁-C₅₀ alkoxy, a substituted or unsubstituted C₁-C₅₀ alkoxycarbonyl, a substituted or unsubstituted C₆-C₆₀ aryl, a substituted or unsubstituted C₁-C₆₀ heteroaryl, a substituted or unsubstituted C₆-C₆₀ aryloxy, a substituted or unsubstituted C₆-C₅₀ arylthio, a halogen, a cyano, a hydroxyl, and a carbonyl；

R₅ is a substituted or unsubstituted C₁-C₃₀ alkyl； a substituted or unsubstituted C₃-C₅₀ cycloalkyl； a substituted or unsubstituted C₆-C₆₀ aryl； or a substituted or unsubstituted C₁-C₆₀ heteroaryl；

Ar₁ and Ar₂ are each independently selected from the group consisting of a substituted or unsubstituted C₆-C₆₀ aryl, and a substituted or unsubstituted C₁-C₆₀ heteroaryl； and

X₁ and X₂ are each independently a chemical bond, or selected from the group consisting of a substituted or unsubstituted C₁-C₅₀ alkylene, a substituted or unsubstituted C₃-C₅₀ cycloalkylene, a substituted or unsubstituted C₆-C₆₀ arylene, and a substituted or unsubstituted C₁-C₆₀ heteroarylene.
The organic compound of Claim 1, wherein the organic compounds are selected from the following structures (7) through (22) :
An electronic device comprising an organic layer, wherein the organic layer comprises the organic compound of any one of Claims 1-13.
The electronic device of Claim 14, wherein the organic layer is a hole transport layer, an emissive layer, an electron transport layer, or a hole injection layer.
The electronic device of claim 14, wherein the electronic device is a light emitting device.