Description
NEW COMPOUND AND ORGANIC LIGHT EMITTING DEVICE
USING THE SAME (2)
Technical Field
[1] The present invention relates to an organic light emitting device which comprises a
fluorene derivative capable of significantly improving a lifespan, efficiency, and electrochemical
and thermal stabilities thereof.
[2]
Background Art
[3] An organic light emission phenomenon is an example of a conversion of current
into visible rays through an internal process of a specific organic molecule. The
organic light emission phenomenon is based on the following mechanism. When
organic material layers are interposed between an anode and a cathode, if voltage is
applied between the two electrodes, electrons and holes are injected from the cathode
and the anode into the organic material layer. The electrons and the holes which are
injected into the organic material layer are recombined to form an exciton, and the
exciton is reduced to a bottom state to emit light. An organic light emitting device
which is based on the above mechanism typically comprises a cathode, an anode, and
organic material layer(s), for example, organic material layers including a hole
injection layer, a hole transport layer, a light emitting layer, and an electron transport
layer, inteiposed therebetween.
[4] The materials used in the organic light emitting device are mostly pure organic
materials or complexes of organic material and metal. The material used in the organic
light emitting device may be classified as a hole injection material, a hole transport
material, a light emitting material, an electron transport material, or an electron
injection material, according to its use. In connection with this, an organic material
having a p-type property, which is easily oxidized and is electrochemically stable when
it is oxidized, is mostly used as the hole injection material or the hole transpon
material. Meanwhile, an organic material having an n-type property, which is easily
reduced and is electrochemically stable when it is reduced, is used as the electron
injection material or the electron transport material. As the light emitting layer
material, an organic material having both p-type and n-type properties is preferable,
which is stable when it is oxidized and when it is reduced. Also a material having high
light emission efficiency for conversion of the exciton into light when the exciton is
formed is preferable.
[5] In addition, it is preferable that the material used in the organic light emitting device
further have the following properties.
[6] First, it is preferable that the material used in the organic light emitting device have
excellent thermal stability. The reason is that joule heat is generated by movement of
electric charges in the organic light emitting device. NPB, which has recently been
used as the hole transport layer material, has a glass transition temperature of 100°C or
lower, thus it is difficult to apply to an organic light emitting device requiring a high
current.
[7] Second, in order to produce an organic light emitting device that is capable of being
actuated at low voltage and has high efficiency, holes and electrons which are injected
into the organic light emitting device must be smoothly transported to a light emitting
layer, and must not be released out of the light emitting layer. To achieve this, a
material used in the organic light emitting device must have a proper band gap and a
proper HOMO or LUMO energy levels. A LUMO energy level of PEDOT:PSS, which
is currently used as a hole transport material of an organic light emitting device
produced using a solution coating method, is lower than that of an organic material
used as a light emitting layer material, thus it is difficult to produce an organic light
emitting device having high efficiency and a long lifespan.
[8] Moreover, the material used in the organic light emitting device must have excellent
chemical stability, electric charge mobility, and interfacial characteristic with an
electrode or an adjacent layer. That is to say, the material used in the orgajnic light
emitting device must be little deformed by moisture or oxygen. Furthermore, proper
hole or electron mobility must be assured so as to balance densities of the holes and of
the electrons in the light emitting layer of the organic light emitting device to
maximize the formation of excitons. Additionally, it has to be able to have a good
interface with an electrode including metal or metal oxides so as to assure stability of
the device.
Accordingly, there is a need to develop an organic light emitting device including
an organic material having the above-mentioned requirements in the art.
[10]
Disclosure of Invention
Technical Problem
[11] Therefore, the object of the present inventions is to provide an organic light
emitting device which is capable of satisfying conditions required of a material usable
for an organic light emitting device, for example, a proper energy level, electrochemical
stability, and thermal stability, and which includes a fluorene derivative
having a chemical structure capable of playing various roles required in the organic
light emitting device, depending on a substiruent group.
Technical Solution
The present invention provides an organic light emitting device which comprises a
first electrode, organic material layer(s) comprising a light emitting layer, and a second
electrode, wherein the first electrode, the organic material layer(s), and the second
electrode form a layered structure and at least one layer of the organic material layer(s)
includes a compound of the following Formula 1 or a compound of Formula 1 into
which a thermoserting or photo-crosslinkable functional group is introduced:
[Formula 1]
R3
In Formula 1, X is C or Si, A is NZ1Z2, and B is NZ3Z4.
Y is a bond; bivalent aromatic hydrocarbons; bivalent aromatic hydrocarbons which
are substituted with at least one substituent group selected from the group consisting of
nitro, nitrile, halogen, alkyl, alkoxy, and amino groups; a bivalent heterocyclic group;
or a bivalent heterocyclic group which is substituted with at least one substituent group
selected from the group consisting of nitro, nitrile, halogen, alkyl, alkoxy, and amino
groups.
Zl to Z4 are each independently hydrogen; aliphatic hydrocarbons having a carbon
number of 1 - 20: aromatic hydrocarbons; aromatic hydrocarbons which are substituted
with at least one substituent group selected from the group consisting of the nitro.
nitrile, halogen, alkyl, alkoxy, amino. aromatic hydrocarbon, and heterocyclic groups;
a silicon group substituted with aromatic hydrocarbons; a heterocyclic group; a heterocyclic
group which is substituted with at least one substituent group selected from
the group consisting of the nitro, nitrile, halogen, alkyl, alkoxy, amino, aromatic hydrocarbon,
and heterocyclic groups; a thiophenyl group which is substituted with hydrocarbons
having a carbon number of 1 - 20 or aromatic hydrocarbons having a
carbon number of 6 - 20; or a boron group which is substituted with aromatic hydrocarbons.
[19] Rl to Rl 1 are each independently hydrogen, a substituted or unsubstituted alkyl
group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted
alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted
arylamine group, a substituted or unsubstituted heterocyclic group, an amino group, a
nitrile group, a nitro group, a halogen group, an amide group, or an ester group. They
may form aliphatic or hetero condensation rings along with adjacent groups.
[20] R7 and R8 may be directly connected to each other, or may form a condensation
ring along with a group selected from the group consisting of O, S, NR, PR, C=O,
CRR', and SiRR'. R and R' are each independently or collectively hydrogen, a
substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a
substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, a
substituted or unsubstituted arylamine group, a substituted or unsubstituted heterocyclic
group, a nitrile group, an amide group, or an ester group, and may form a
condensation ring to form a spiro compound.
[21] A detailed description will be given of the substituent groups of Formula 1.
[22] In Zl to Z4 as the substituent groups of Formula 1, the aromatic hydrocarbons are
exemplified by monocyclic aromatic rings, such as phenyl, biphenyl, and terphenyl,
and multicyclic aromatic rings, such as naphthyl, anthracenyl. pyrenyl, and perylenyl.
The heterocyclic group is exemplified by thiophene. furan, pyrrole, imidazole.
thiazole, oxazole, oxadiazole, thiadiazole, triazole, pyridyl, pyridazyl, pyrazine.
quinoline, and isoquinoline.
[23] Examples of aliphatic hydrocarbons having a carbon number of 1 - 20 include
straight chain aliphatic hydrocarbons, branched chain aliphatic hydrocarbons, saturated
aliphatic hydrocarbons, and unsaturated aliphatic hydrocarbons. They are exemplified
by an alkyl group, such as a methyl group, an ethyl group, an n-propyl group, an isopropyl
group, an n-butyl group, a sec-butyl group, an iso-butyl group, a ter-butyl
group, a pentyl group, and a hexyl group; an alkenyl group having a double bond, such
as styryl: and an alkynyl group having a triple bond, such as an acetylene group.
[24] The carbon number of the alkyl, alkoxy. and alkenyl groups of Rl to Rl 1 of
Formula 1 is not limited, but is preferably 1 - 20.
[25] The length of the alkyl group contained in the compound does not affect the
conjugate length of the compound, but may affect the method of applying the
compound to the organic light emitting device, for example, a vacuum deposition
method or a solution coating method.
[26] Illustrative, but non-limiting, examples of the aryl group of Rl to Rl 1 of Formula 1
include monocyclic aromatic rings, such as a phenyl group, a biphenyl group, a
terphenyl group, and a stilbene group, and multicyclic aromatic rings, such as a
naphthyl group, an anthracenyl group, a phenanthrene group, a pyrenyl group, and a
perylenyl group.
[27] Illustrative, but non-limiting, examples of the arylamine group of Rl to Rl 1 of
Formula 1 include a diphenylamine group, a dinaphthylamine group, a
dibiphenylamine group, a phenylnaphthylamine group, a phenyldiphetylamine group, a
ditolylamine group, a phenyltolylamine group, a carbazolyl group, and a triphenylamine
group.
[28] Illustrative, but non-limiting, examples of the heterocyclic group of Rl to Rl 1 of
Formula 1 include a thiophenyl group, a furan group, a pyrrolyl group, an imidazolyl
group, a thiazolyl group, an oxazolyl group, an oxadiazolyl group, a triazolyl group, a
pyridyl group, a pyradazine group, a quinolinyl group, an isoquinoline group, and an
acridyl group.
[29] In addition, illustrative, but non-limiting, examples of the alkenyl, aryl, arylamine,
and heterocyclic groups of Rl to Rl 1 of Formula 1 include groups shown in the
following Formulae.
[30]
[31] In the above Formulae, Z is a group selected from the group consisting of hydrogen,
aliphatic hydrocarbons having a carbon number of 1 - 20, an alkoxy group, an
arylamine group, an aryl group, a heterocyclic group, a nitrile group, and an acetylene
group. Examples of the arylamine, aryl, and heterocyclic groups of Z are as shown in
the above-mentioned substituent groups of Rl to Rl 1.
132] According to a preferred embodiment of the present invention, X of Formula 1 is C,
and R7 and R8 are directly connected to each other or form a condensation ring along
with a group selected from the group consisting of O, S, NR, PR, C=O, CRR', and
SiRR' (R and R1 are as defined in Formula 1).
133] According to another preferred embodiment of the present invention, X of Formula
1 is Si, and R7 and R8 are directly connected to each other or form a condensation ring
along with a group selected from the group consisting of O, S, NR, PR, C=O, CRR',
and SiRR' (R and R1 are as defined in Formula 1).
[34] According to still another preferred embodiment of the present invention, the
compound of Formula 1 is any one of the compounds of Formulae 2 to 5.
[35]
[Formula 2] [Formula 3]
[formula 4]
6R
[Formula 5]
in the Formulae 2 to 5, A and B are as defined in claim 1.
Illustrative, but non-limiting, examples of A and B are as follows. Combination of
the compounds of Formulae 2 to 5 and the following groups can form various
derivative compounds. For example, if the compound of Formula 2 is combined with
the group 1 of rhe A and B groups, the resulting product will be designated by the
compound of Formula 2-1.
[A and B groups]
(Figure Removed)
Brief Description of the Drawings
FIG. 1 illustrates an organic light emitting device comprising a substrate 1, an
anode 2, a light emitting layer 3, and a cathode 4; and
FIG. 2 illustrates an organic light emitting device comprising a substrate 1, an
anode 2, a hole injection layer 5, a hole transport layer 6, a light emitting layer 7, an
electron transport layer 8, and a cathode 4.
Best Mode for Carrying Out the Invention
Hereinafter, a detailed description will be given of the present invention.
Various substituent groups are introduced into a core structure shown in Formula 1,
in detail, the core structure in which a fluorene group is bonded to a combination of an
acridine group and a carbazolyl group to form a spiro structure, thereby the compound
of Formula 1 has characteristics suitable for application to an organic material layer
used in an organic light emitting device. This will be described in detail, below.
The steric core structure of the compound of Formula 1, for convenience of explanation,
can be divided into two portions, A and B, as shown in the following
Formula.
(Figure Removed)
The compound of Formula 1 has the steric core structure in which a plane A meets
with a plane B at right angles around X, and conjugation does not occur between the A
and B portions around X. Furthermore, since one nitrogen atom is positioned among
three aryl groups in the plane B, conjugation is limited in the plane B.
The conjugation length of the compound has a close relationship with an energy
band gap. In detail, the energy band gap is reduced as the conjugation length of the
compound increases. As described above, since a conjugation structure is limited in the
core structure of the compound of Formula 1, the core structure has a large energy
band gap.
[50] As described above, in the present invention, various substituent groups are
introduced to Rl to Rl 1 positions and Zl to Z4 positions of the core structure having
the large energy band gap so as to produce compounds having various energy band
gaps. Generally, it is easy to control the energy band gap by introducing substituent
groups into a core structure having a large energy band gap, but it is difficult to significantly
control the energy band gap by introducing substituent groups into a core
structure having a small energy band gap. Furthermore, in the present invention, it is
possible to control HOMO or LUMO energy levels of the compound by introducing
various substituent groups into the Rl to Rl 1 and Zl to Z4 positions of the core
structure.
[51] Additionally, by introducing various substituent groups into the core structure,
compounds having intrinsic characteristics of the substituent groups can be
synthesized. For example, substituent groups, which are frequently applied to hole
injection layer materials, hole transport layer materials, light emitting layer materials,
and electron transport layer materials which are used during the production of the
organic light emitting device, are introduced into the core structure so as to produce
substances capable of satisfying requirements of each organic material layer. For
example, since the core structure of the compound of Formula 1 includes the arylamine
structure, it has an energy level suitable for the hole injection and/or hole transport
materials in the organic light emitting device. In the present invention, the compound
having the proper energy level is selected depending on the substituent group among
the compounds represented by Formula 1 to be used in the organic light emitting
device, thereby it is possible to realize a device having a low actuating voltage and a
high light efficiency.
[52] Furthermore, various substituent groups are symmetrically introduced into the core
structure (the A and B portions are located at both sides of the core structure) so as to
precisely control the energy band gap, improve interfacial characteristics with organic
materials, and apply the compound to various fields.
[53] As well, if the numbers of nitrogen contained in the substituent groups A and B are
each set to 1 (if Zl to Z4 are hetero aromatic amine compounds, the number of
nitrogen contained in them is not counted), it is possible to precisely control the
HOMO and LUMO energy levels and the energy band gap. and on the other hand interfacial
characteristics with the organic materials is improved and thereby make it
possible to apply the compound to various fields.
[54] Additionally, various substituent groups are introduced into the steric structure of
the compound of Formula 1 using spiro bonding to control the three-dimensional
structure of the organic material so as to minimize ^-.i interaction in the organic
material, thereby formation of excimers is prevented,
[55] With respect to the energy band gap and the energy level, for example, since the
compound of Formula 2-1, in which arylamine is introduced into the hole transport
material or the hole injection material of the structure of Formula 1, has HOMO of
5.37 eV, it has an energy level suitable for the hole injection layer or the hole transport
layer. Meanwhile, the compound of Formula 2-1 has the band gap of 3.09 eV, which is
still larger than that of NPB, typically used as the hole transport layer material, thus it
has a LUMO value of about 2.28 eV, which is considered to be very high. If a
compound having a high LUMO value is used as the hole transport layer, it increases
the energy wall of LUMO of the material constituting the light emitting layer to
prevent the movement of electrons from the light emitting layer to the hole transport
layer. Accordingly, the above-mentioned compound improves the light emission
efficiency of the organic light emitting device so that efficiency is higher than that of
conventionally used NPB (HOMO 5.4 eV, LUMO 2.3 eV, and energy band gap 3.1
eV). In the present invention, the energy band gap is calculated by a typical method
using a UV-VIS spectrum.
[56] As well, the compound of Formula 1 has stable redox characteristics. Redox
stability is estimated using a CV (cyclovoltammetry) method. For example, if
oxidation voltage is repeatedly applied to the compound of Formula 2-1, oxidation
repeatedly occurs at the same voltage and the current amount is constant. This means
that the compound has excellent stability to oxidation.
[57] Meanwhile, since the compound of Formula 1 has a high glass transition
temperature (Tg), it has excellent thermal stability. For example, the glass transition
temperature of the compound of Formula 2-1 is 131 °C, which is still higher than that of
conventionally used NPB (Tg: 96°C). Such increase in thermal stability is an important
factor providing actuating stability to the device.
158] Furthermore, the compound of Formula 1 may be used to form the organic material
layer using a vacuum deposition process or a solution coating process during the
production of the organic light emitting device. In connection with this, illustrative, but
non-limiting, examples of the solution coating process include a spin coating process, a
dip coating process, an inkjet printing process, a screen printing process, a spray
process, and a roll coating process.
159] For example, the compound of Formula 2-1 has excellent solubility to a polar
solvent, such as xylcne. dichloroethane, or NMP. which is used during the production
of the device, and fonns a thin film very well through the process using a solution, thus
the solution coating process may be applied to produce the device. Additionally, a light
emitting wavelength of a thin film or a solid formed using the solution coating process
is typically shifted to a longer wavelength due to interaction between molecules, in
comparison with a light emitting wavelength in a solution state. Little shift in the
wavelength occurs in the compound having the structure shown in Formula 1.
[60] Tertiary alcohol, which is produced by a reaction of a lithiated aryl and keto group,
is heated in the presence of an acid catalyst to form a hexagonal cyclic structure while
water is removed, thereby producing the compound having a spiro structure according
to the present invention. The above-mentioned procedure for producing the compound
is well known in the art, and those skilled in the art can change the production
conditions during the production of the compound of Formula 1. The production will
be described in detail in the preparation examples later.
[61] In the organic light emitting device of the present invention, a compound, in which
a thermosetting or photo-crosslinkable functional group is introduced into the
compound of Formula 1, for example, the compound of Formula 2-61, may be used
instead of the compound of Formula 1. The former compound has the basic physical
properties of the compound of Formula 1, and may be used to form a thin film using a
solution coating process and then be cured so as to form an organic material layer
during the production of the device.
[62] The method of forming the organic material layer, which comprises introducing the
curable functional group into the organic material during the production of the organic
light emitting device, forming the organic thin film using the solution coating process,
and curing the resulting film, is disclosed in US Pat. No. 2003-0044518 and EP Pat. ,
No. 1146574 A2.
[63] The above documents state that, if the organic material layer is formed through the
above-mentioned method using a material having a thermosetting or photocrosslinkable
vinyl or acryl group so as to produce an organic light emitting device, it
is possible to produce an organic light emitting device having a low voltage and high
brightness as well as an organic light emitting device having a multilayered s tincture
using the solution coating process. This operation mechanism may be applied to the
compound of the present invention.
164] In the present invention, the thermosetting or photo-crosslinkable functional group
may be a vinyl or acryl group.
165] The organic light emitting device of the present invention can be produced using
known materials through a known process, modified only in that at least one layer of
organic material layer(s) include the compound of the present invention, that is, the
compound of Formula 1.
[66] The organic material layer(s) of the organic light emitting device according to the
present invention may have a single layer structure, or alternatively, a multilayered
structure in which two or more organic material layers are layered. For example, the
organic light emitting device of the present invention may comprise a hole injection
layer, a hole transport layer, a light emitting layer, an electron transport layer, and an
electron injection layer as the organic material layer(s). However, the structure of the
organic light emitting device is not limited to this, but may comprise a smaller number
of organic material layers.
[67] Furthermore, the organic light emitting device of the present invention may be
produced, for example, by sequentially layering a first electrode, organic material
layer(s), and a second electrode on a substrate. In connection with this, a physical
vapor deposition (PVD) method, such as a sputtering method or an e-beam evaporation
method, may be used, but the method is not limited to these.
[68] A method of producing the compound of Formula 1 and the production of the
organic light emitting device using the same will be described in detail in the following
preparation examples and examples. However, the following preparation examples and
examples are set forth to illustrate, but are not to be construed to limit the present
invention.
[69]
Mode for the Invention
[70] A better understanding of a method of producing an organic compound represented
by Formula 1 and the production of an organic light emitting device using the same
may be obtained in light of the following preparation examples and examples which
are set forth to illustrate, but are not to be construed to limit the present invention.
[71 ] In order to produce the compound represented by Formula 1, any one of the
compounds of the following Formulae, a to c, may be used as a starting material.
[72]
Ifornula a] [Fomulab] [Formula CJ
173]
174] PREPARATION EXAMPLE 1 -.Preparation of a starting material represented by
Formula a
175]
[76] Carbazole (1.672 g. 10 mmol). l-bromo-2-iodobeiuene (1.5 ml, 12 mmol),
potassium carbonate (K^CO . 2.7646 g, 20 mmol). copper iodide (Cul, 95 mg, 0.5
mmol), and 25 ml of xylene were refluxed in a nitrogen atmosphere. After cooling to
normal temperature was conducted, a product was extracted with ethyl acetate, water
was removed with anhydrous magnesium sulfate (MgSO ), and the solvent was
removed at a reduced pressure. The resulting product was passed through a silica gel
column using a bexane solvent to produce a compound, the solvent was removed at a
reduced pressure, and vacuum drying was conducted to produce the resulting white
solid compound (800 mg, 25 % yield). MS: [M+HJ* = 323.
[77]
[78] PREPARATION EXAMPLE 2: Preparation of a starting material represented by
Formula b
[79]
[80] The starting material represented by Formula a (6.96 g, 21.6 mmol) was dissolved
in 300 ml of purified THF and cooled to -78°C, and n-BuLi (2.5 M in hexane, 8.64 ml,
21.6 mmol) was slowly dropped thereon. Stirring was conducted at the same
temperature for 30 min, and 2,7-dibromo-9-fluorenone (6.08 g, 18.0 mmol) was added
thereto. After stirring was conducted at the same temperature for 40 min, the
temperature was raised to normal temperature and stirring was carried out for an
additional 3 hours. The reaction was completed in an ammonium chloride (NH Cl)
aqueous solution, and extraction was conducted with ethyl ether. Water was removed
from an organic material layer using anhydrous magnesium sulfate (MgSO ), and an
organic solvent was then removed therefrom. The produced solid was dispersed in
ethanol. stirred for one day. filtered, and vacuum dried to produce 10. 1 2 g of intermediate
material (96.7 yield). The intermediate solid was dispersed in 10 ml of
acetic acid, ten drops of concentrated sulfuric acid were added thereto, and reflux was
conducted for 4 hours. The resulting solid was filtered, washed with ethanol, and
vacuum dried to produce 9.49 g of compound of Formula b (96.8 r yield). MS: (M+H
]+ = 563.
[82] PREPARATION EXAMPLE 3: Preparation of a starting material represented by
Formula c
[83]
[84] The starting rr.aterial represented by Formula b (10.0 g, 17.8 mmol) was completely
dissolved in 200 ml of THF. 4-chloro-phenylboronic acid (8.30g. 53.3 mmol), 2M
potassium carbonate solution, tetrakis(triphen\iphosphine)palladium(0) (0.62 g, 0.53
mmol). and 10 ml of ethanol were added thereto, and reflux was conducted for 24
hours. After the reaction was completed, cooling to normal temperature was
conducted, and nitration was conducted. Washing was conducted with water and
ethanol several times. Recrystallization was conducted with ethanol. and vacuum
drying was conducted to produce a compound i>>.5 g, 85 % yield). MS: [M+H]+= 625.
EXAMPLE 1: Preparation of the compound represented by Formula 2-1
After the compound of Formula b (3.0 g, 5.3 mmol) was dispersed in 50 ml of
icylene, diphenylamine (2.07 g, 12.2 mmol), sodium tert-butoxide (0.074 g, 0.370
mmol), tris(dibenzylideneaeetone)dipalladium(0) (Pd^(dba), 0.14 g, 0.25 mmol), and
tri-t-butylphosphine (3.50 g, 36.7 mmol) were sequentially added thereto, and reflux
was conducted at 120°C for 2 hours. After cooling to normal temperature was
conducted, water was added thereto, a layer separation process was conducted, and
water and the solvent were removed from an organic layer. The resulting substance
was dispersed in ethyl acetate, and stirred for one day. The solid was filtered and
vacuum dried. The resulting solid was subjected to a column separation process using
n-hexane/tetrahydrofuran m-hexane/THF = 4/1), and the product was dispersed in
ethanol, boiled therein, stirred, and filtered to produce 1.7 g of compound of Formula
2-1 (43 % yield). MS: [M+H]+= 740.
EXAMPLE 2: Preparation of the compound represented by Formula 2-2
After the compound of Formula b (1.13 g, 2.00 mmol) was dispersed in 20 ml of
xylene, N-phenyl-1-naphthylamine (0.965 g, 4.40 mmol), sodium tert-butoxide (0.433
g, 4.50 mmol), tris(dibenzylideneacetone)dipalladium(0) (Pd^dba), 0.073 g. 0.080
mmol), and 50 wt% tri-t-butylphosphine (0.024 g. 0.120 mmol) were sequentially
added thereto, and reflux was conducted at 120°C for 1.5 hours. After cooling to
normal temperature was conducted, water was added thereto, a layer separation
process was conducted, and water and the solvent were removed from an organic layer.
The resulting substance was dispersed in ethyl acetate, and stirred for one day. The
solid was filtered and vacuum dried. The resulting solid was subjected to a column
separation process using n-hexane/tetrahydrofuran (n-hexane/THF = 4/1), and the
product was dispersed in ethanol, boiled therein, stirred, and filtered to produce 0.680
g of compound of Formula 2-2 (40.5 % yield). MS: [M+H]+= 841.
EXAMPLE 3: Preparation of the compound represented by Formula 2-3
The compound of Formula b (2.5 g, 4.4 mmoD and N-phenyl-2-naphthylamine (2.2
g, 10 mmol) were dissolved in 50 ml of toluene, sodium-tert-butoxide (1.26 g. 13.2
mmol), tris(dibenzylidene acetone)dipalladium(0N> (Pd (dba), 0.08 g, 0.08 mmol), and
50 wt% tri-ten-butylphosphine (0.02 g, 0.13 mmol) were added thereto, and reflux was
conducted in a nitrogen atmosphere for 2 hours. Distilled water was added to the
reaction solution to complete the reaction, and the organic layer was extracted. A
column separation process was conducted using a solvent of n-hexane and
tetrahydrofuran (n-hexane/THF = 4/1), recrystallization was conducted with ethanol,
and vacuum drying was conducted to produce the compound of Formula 2-3 (1.92 g,
yield 52 %). MS: [M+H]+= 839.
[97]
[98] EXAMPLE 4: Preparation of the compound represented by Formula 2-4
[99]
[ 100] 1) Synthesis of arylamine (N-phenyl-4-biphenylamine) to produce the compound
represented by Formula 2-4: aniline (10 ml, 109.74 mmolt and 4-bromobiphenylamine
(25.6 g, 109.7 mmol) were dissolved in 300 ml of toluene, and bis(dibenzylidene
acetone)palladium(0" (Pd(dba) . 1.26 g, 2.20 mmol), 50.\vt% tri-tert-butylphosphine
toluene solution (1.30 ml, 3.29 mmol), and sodium-tert-butoxide (21.09 g, 219.5
mmol) were added thereto. Reflux was conducted in a nitrogen atmosphere for 2 hours,
and distilled water was added to the reaction solution to complete the reaction. The
organic layer was extracted, a column separation process was conducted using a
developing solvent of n-hexane and tetrahydrofuran (n-hexane/THF = 10/1), stirring
was conducted using petroleum ether, and vacuum drying was conducted to produce
arylamine (15 g, yield 56 £). MS: [M+Hf= 246.
[101] 2) The compound of Formula b (2.5 g, 4.44 mmol) and N-phenyl-4-biphenylamine
(2.72 g, 11.1 mmol) were dissolved in 30 ml of toluene, and bis(diben7.ylidene
acetone)palladium(0 • (Pd(dba)^ 0.051 g, 0.09 mmol), 50 wt% tri-tert-butylphosphine
toluene solution (0.05 ml, 0.13 mmol), and sodium-tert-butoxide (1.707 g, 17.76
mmol) were added thereto. After reflux was conducted in a nitrogen atmosphere for 2
hours, distilled water was added to the reaction solution to complete the reaction. The
organic layer was extracted, a column separation process was conducted using a
developing solvent of n-hexane and tetrahydrofuran (n-hexane/THF = 10/1), stirring
was conducted using petroleum ether, and vacuum drying was conducted to produce
the compound of Formula 2-4 (3.2 g, yield 80.8 %). MS: [M+H]*= 893.
1102]
1103] EXAMPLE 5: Preparation of the compound represented by Formula 2-6
[104]
[ 105] 1) Synthesis of arvlamine (1.1-dinaphthylamine'l to produce the compound
represented by Formula 2-6: 1-aminonaphthalene (10.0 g. 69.84 mmol) and
1-bromonaphthalene (7.47 ml, 53.7 mmol) were dissolved in 200 ml of toluene, and
tris(dibenzylidene acetonejdipalladium(O) (Pd^(dba), 1.21 g, 2.10 mmol), 50 \vt% tritert-
butylphosphine (1.38 ml, 2.79 mmol), and sodium-tert-butoxide (16.78 g, 174.6
mmol) were added thereto. Reflux was conducted in a nitrogen atmosphere for 2 hours,
and distilled water was added to the reaction solution to complete the reaction. The
organic layer was extracted, a column separation process was conducted using a
developing solvent of n-hexane and tetrahydrofuran (n-hexane/THF = 15/1), stirring
was conducted using petroleum ether, and vacuum drying was conducted to produce
arylamine (5.26 g, yield 28 %). MS: [M+Hf= 270.
[106] 2) The compound of Formula b (5.0 g, 8.88 mmol) and 1,1-dinaphthylamine (5.26
g, 19.5 mmol) were dissolved in 50 ml of toluene, and bis(dibenzylidene
acetone)palladium(O) (Pd(dba), 0.204 g, 0.36 mmol), 50 wt% tri-tert-butylphosphine
toluene solution (0.31 ml, 0.62 mmol), and sodium-tert-butoxide (4.694 g, 48.84
mmol) were added thereto. After reflux was conducted in a nitrogen atmosphere for 2
hours, distilled water was added to the reaction solution to complete the reaction. The
organic layer was extracted, a column separation process was conducted using a
developing solvent of n-hexane and tetrahydrofuran (n-hexane/THF = 9/1), stirring
was conducted using petroleum ether, and vacuum drying was conducted to produce
the compound of Formula 2-6 (3.29 g, yield 39.4 %). MS: [M+H]*= 941.
[107]
[ 108] EXAMPLE 6: Preparation of the compound represented by Formula 2-8
[109]
[110] 1) Synthesis of arylamine (1.4-naphthylbiphenylamine) to produce the compound
represented by Formula 2-8: 1-aminonaphthalene (7.4 g, 51.48 mmol) and
4-bromobiphenyl (12 g, 51.48 mmol) were dissolved in 200 ml of toluene, and
bis(dibenzylidene acetone)palladium(O) (Pd(dba)v 0.89 g, 1.54 mmol), 50 wt<*- tritert-
butylphosphine (0.60 ml, 1.54 mmol), and sodium-tert-butoxide (9.90 g, 103.0
mmol) were added thereto. Reflux was conducted in a nitrogen atmosphere for 2 hours,
and distilled water was added to the reaction solution to complete the reaction. The
organic layer was extracted, a column separation process was conducted using a
developing solvent of n-hexane and tetrahydrofuran (n-hexane/THF = 15/1), stirring
was conducted using petroleum ether, and vacuum drying was conducted to produce
arylamine (6.3 g, yield 42 %). MS: [M+Hf= 295.
[ I l l ] 2) The compound of Formula b (3 g. 5.33 mmol) and 1,4-naphthylbiphenylamine
(3.62 g, 12.25 mmol* were dissolved in SO ml of toluene, and bis(dibenzylidene
acetone)palladium(0'i (Pd(dba) . 0.06 g, 0.11 mmol), 50 wt% tri-tert-butylphosphine
toluene solution (0.06 ml, 0.16 mmol;, and sodium-tert-butoxide (1.54 g, 16.0 mmol)
were added thereto. After reflux was conducted in a nitrogen atmosphere for 2 hours,
distilled water was added to the reaction solution to complete the reaction. The organic
layer was extracted, a column separation process was conducted using a developing
solvent of n-hexane and tetrahydrofuran vn-hexane/THF = 9/1), stirring was conducted
using petroleum ether, and vacuum drying was conducted to produce the compound of
Formula 2-8 (3.2 g, yield 61 %). MS: [M+H]*= 992.
[112]
[113] EXAMPLE 7: Preparation of the compound represented by Formula 2-12
[114]
[115] 1) Synthesis of arylamine (4,4-dibiphenylamine) to produce the compound
represented by Formula 2-12: 4-aminobiphenyl (30.5 g, 180.17 mmol) and
4-bromobiphenyl (40 g, 171.59 mmol) were dissolved in 500 ml of toluene, and
bis(dibenzylidene acetone)palladium(0) (Pd(dba), 2.07 g, 3.60 mmol), 50 wt% tritert-
butylphosphine (2.2 ml, 5.41 mmol), and sodium-tert-butoxide (51.94 g, 540.5
mmol) were added thereto. Reflux was conducted in a nitrogen atmosphere for 2 hours,
and distilled water was added to the reaction solution to complete the reaction. The
organic layer was extracted, a column separation process was conducted using a
developing solvent of n-hexane and tetrahydrofuran (n-hexane/THF = 15/1), stirring
was conducted using petroleum ether, and vacuum drying was conducted to produce
4,4-dibiphenylamine (32 g, yield 58 %). MS: [M+H]+= 321.
f 116] 2) The compound of Formula b (5.4 g, 0.62 mmol) and 4,4-dibiphenylamine '(6.80
g, 2.12 mmol) were dissolved in 200 ml of toluene, and bis(dibenzylidene
acetone)palladium(O) (Pd(dba)y 0.243 g, 0.423 mmol), 50 wt% tri-tert-butylphosphine
toluene solution (0.260 ml, 0.635 mmol), and sodium-tert-butoxide (6.10 g, 63.5
mmol) were added thereto. After reflux was conducted in a nitrogen atmosphere for 2
hours, distilled water was added to the reaction solution to complete the reaction. The
organic layer was extracted, a column separation process was conducted using a
developing solvent of n-hexane and tetrahydrofuran (n-hexane/THF = 9/1), stirring
was conducted using petroleum ether, and vacuum drying was conducted to produce
the compound of Formula 2-12 (6.3 g, yield 63 %). MS: [M+H]+= 1044.
[117]
[ 118| KXAMPLE 8: Preparation of the compound represented by Formula 2-18
(1191
[120] The compound of Formula b (2.5 g, 4.4 mmol) and 4-methyldiphenylamine (2.0 g,
10 mmol) were dissolved in 50 ml of xylene. sodium-tert-butoxide (1.26 g, 13.2
mmol), trisfdibenzylidene acetone)dipalladium(O) (Pd^dbaj . 0.08 g, 0.08 mmol). and
50 wt9f tri-tert-butylphosphine (0.02 g, 0.13 mmol) were added thereto, and reflux was
conducted in a nitrogen atmosphere for 2 hours. Distilled water was added to the
reaction solution to complete the reaction, and the organic layer was extracted. A
column separation process was conducted using a solvent of n-hexane and
tetrahydrofuran (n-hexane/THF = 4/1), recrystallization was conducted with ethanol,
and vacuum drying was conducted to produce the compound of Formula 2-18 (1.8 g,
yield 52 %). MS: [M+H]+= 768.
[121]
[122] EXAMPLE 9: Preparation of the compound represented by Formula 2-59
[123]
[124] 1) The compound of Formula b (2.25 g, 4 mmol) and aniline (0.8 ml, 8.8 mmol)
were dissolved in 40 ml of xylene, and tri-tert-butylphosphine (0.05 g, 0.24 mmol) and
tris(dibenzylidene acetone)dipalladium(O) (Pd (dba), 0.15 g, 0.16 mmol) were sequentially
added thereto. After reflux was conducted for 6 hours, cooling to normal
temperature was conducted, and water was added thereto. The organic layer was
separated, and a column separation process was conducted using n-hexane and
tetrahydrofuran (n-hexane/THF = 4/1) to produce 1.23 g of a light brown solid. MS:
[M+H]+= 588.
[125] 2) 0.59 g of the above compound (1 mol), 4-bromostyrene (0.28 ml, 2.1 mmol),
sodium-tert-butoxide (0.21 g, 2.2 mmol), tri-tert-butylphosphine (0.012 g, 0.06 mmol),
and tris(dibenzylidene acetone)dipalladium(O) (Pd^(dba) , 0.037 g, 0.04 mmol) were
added to xylene, and reflux was conducted for 3 hours. After cooling to normal
temperature, water was added thereto, the organic layer was extracted, and a column
separation process was conducted using n-hexane and tetrahydrofuran (n-hexane/THF
= 4/1) to produce the compound of Formula 2-59 (0.2 g). MS: [M+H]*= 792.
[126]
[127] EXAMPLE 10: Preparation of the compound represented by Formula 2-61
[128]
[129] The compound of Formula b (1.12 g, 2.0 mmol) and 4-dodecylaniline (0.53 g, 2.0
mmol) were dissolved in distilled toluene (30 ml), sodium-tert-butoxide (0.58 g. 6.0
mmol), tris(dibenzylidene acetone)dipalladium(O) (Pd (dbaX, 0.046 g, 0.05 mmol), and
tri-tert-butylphosphine (0.06 g, 0.3 mmol) were added thereto, and stirring was
conducted in a nitrogen atmosphere at 100°C. After 36 hours, ammonia water was
added to the reaction solution to complete the reaction, and the organic layer was
extracted. The extracted organic layer was concentrated in tetrahydrofuran (THF) and
reprecipitated in ethanol. The resulting yellow solid was filtered to separate it. and
additional reprecipitation was repeated twice. The filtered yellow solid was dissolved
in tetrahydrofuran (THF), and then adsorbed onto a silica gel to achieve column
separation, n-hexane and tetrahydrofuran (n-hexane/THF = 4/1) were used as a
developing solvent to remove developed impurities, and a product mixture was
developed with tetrahydrofuran (THF) and thus separated. The separated product
mixture was poured on a celite layer (Celite 545) to be filtered, and the filtered solution
was concentrated with tetrahydrofuran (THF). The concentrated product was reprecipitated
in ethanol, filtered, and vacuum dried to produce a yellow polymer mixture of
Formula 2-61 (0.89 g, yield 54 %).
(Figure Removed)
MALDI-MS: [M+Hf = 3318,3980,4644,5309,5971,6634,7302.
GPC (polystyrene standard)
Mn Mw Mp Mz PDI
10222 19685 22343 31802 1.9
EXAMPLE 11: Preparation of the compound represented by Formula 3-1
The compound of Formula c (5.08 g, 8.11 mmol) and diphenylamine (3.02 g, 17.8
mmol) were dissohed in 100 ml of toluene, sodium-tert-butoxide (5.15 g, 53.6 mmol),
bis(dibenzylidene acetone)palladium(O) (Pd(dba) , 0.21 g, 0.36 mmol), and tritert-
butylphosphine (0.11 ml, 0.54 mmol) were added thereto, and reflux was
conducted in a nitrogen atmosphere for 2 hours. Distilled water was added to the
reaction solution to complete the reaction, and the organic layer was extracted. A
column separation process was conducted using a solvent of n-hexane and
tetrahydroturan (n-hexane/THF = 4/l), recrystallization was conducted with ethanol,
and vacuum drying was conducted to produce the compound of Formula 3-1 (4.30 g.
yield 54.6 7r). MS: [M+H]+= 891.
EXAMPLE 12: Preparation of the compound represented by Formula 3-2
The compound of Formula c (5.0 g, 10.32 mmol) and N-phenyl-1-naphthylamine
(3.85 g, 17.56 mmol) were dissolved in 50 ml of toluene, sodium-tert-butoxide (2.3 g,
23.94 mmol), bis(duce a device except that the
compound of Formula 2-1 used as a hole injection layer was substituted with the
compound of Formula 2-6.
[202] The resulting device had an electric field of 6.50 V at a forward current density of
100 mA/cm2, and a spectrum having a light efficiency of 1.90 Im/W.
[203]
[204] EXAMPLE 22: Production of an organic light emitting device
[205]
[206] The procedure of example 14 was repeated to produce a device except that the
compound of Formula 2-1 used as a hole injection layer was substituted with the
compound of Formula 2-8.
[207] The resulting device had an electric field of 5.49 V at a forward current density of
100 mA/cm2, and a spectrum having a light efficiency of 1.73 Im/W.
[208]
[209] EXAMPLE 23: Production of an organic light emitting device
[210]
[211] The procedure of example 13 was repeated to produce a device except that the
compound of Formula 2-8 was used instead of the compound of Formula 2-1 as a hole
transport layer.
[212] The resulting device had an electric field of 7.13 V at a forward current density of
100 mA/cm", and a spectrum having a light efficiency of 2.08 Im/W.
[213]
[214] EXAMPLE 24: Production of an organic light emitting device
[215]
[216] The procedure of example 14 was repeated to produce a device except that the
compound of Formula 2-1 used as a hole injection layer was substituted with the
compound of Formula 2-12.
[217] The resulting device had an electric field of 7.3 V at a forward current density of
100 mA/cm2, and a spectrum having a light efficiency of 1.75 Im/W.
[218]
[219] EXAMPLE 25: Production of an organic light emitting device
[220]
[221 ] The procedure of example 13 was repeated to produce a device except that the
compound of Formula 2-12 was used instead of the compound of Formula 2-1 as a
hole transport layer.
[222] The resulting device had an electric field of 7.0 V at a forward current density of
100 mA/cm2, and a spectrum having a light efficiency of 1.82 Im/W.
[223]
[224] EXAMPLE 26: Production of an organic light emitting device
[225]
[226] The procedure of example 14 was repeated to produce a device except that the
compound of Formula 2-18 was used instead of the compound of Formula 2-1.
[227] The resulting device had an electric field of 6.68 V at a forward current density of
100 mA/cm2, and a spectrum having a light efficiency of 1.7 Im/W.
[228]
[229] EXAMPLE 27: Production of an organic light emitting device
[230]
[231] The procedure of example 13 was repeated to produce a device except that the
compound of Formula 2-18 was used instead of the compound of Formula 2-1.
[232] The resulting device had an electric field of 6.02 V at a forward current density of
100 mA/cm2, and a spectrum having a light efficiency of 1.48 Im/W.
[233]
[234] EXAMPLE 28: Production of an organic light emitting device
[235]
[236] A glass substrate (corning 7059 glass), on which ITO (indium tin oxide) was
applied to a thickness of 1000 A to form a thin film, was put in distilled water, in
which a detergent was dissolved, and washed using ultrasonic waves. In connection
with this, a product manufactured by Fischer Inc. was used as the detergent, and
distilled water was produced by filtering twice using a filter manufactured by Millippre
Inc. After ITO was washed for 30 min, ultrasonic washing was conducted twice using
distilled water for 10 min. After the washing using distilled water was completed,
ultrasonic washing was conducted using isopropyl alcohol, acetone, and methanol
solvents, and drying was then conducted.
[231] A solution, in which the compound of Formula 2-61 was dissolved in
chlorobenzene in a concentration of 0.5 %, was filtered using a PVDF filter of 0.20
Urn, applied on the substrate using a spin coating process at a speed of 2000 rpm for 20
sec, and dried in an argon atmosphere at 120°C for 5 min to produce a hole injection
layer having a thickness of 350 A.
[238] After the substrate was transported to a vacuum evaporator, Alq3 was deposited
thereon to a thickness of 500 A to form a layer acting both as a light emitting layer and
as an electron transport layer.
[239] Lithium fluoride (LiF) having a thickness of 15 A and aluminum having a thickness
of 1500 A were sequentially deposited on the electron transport layer to form a
cathode.
[240] In the above procedure, the deposition speed of an organic material was maintained
at 0.3 - 0.8 A/sec. Furthermore, lithium fluoride and aluminum were deposited at
speeds of 0.3 A/sec and 1.5 - 2.5 A/sec, respectively, on the cathode. During the
deposition, a vacuum was maintained at 1 - 3 X 10"7.
[241] The resulting device had an electric field of 7.17 V at a forward current density of
100 mA/cm2, and a spectrum having a light efficiency of 0.68 Im/W.
[242]
[243] EXAMPLE 29: Production of an organic light emitting device
[244]
[245] The procedure of example 13 was repeated to produce a device except that the
compound of Formula 2-1 used as a hole transport layer was substituted with the
compound of Formula 3-1.
[246] The resulting device had an electric field of 7.30 V at a forward current density of
100 mA/cm , and a spectrum having a light efficiency of 1.75 Im/W.
[247]
[248] EXAMPLE 30: Production of an organic light emitting device
[249]
[250] The procedure of example 13 was repeated to produce a device except that the
compound of Formula 2-1 used as a hole transport layer was substituted with the
compound of Formula 3-2.
[251] The resulting device had an electric field of 7.50 V at a forward current density of
100 mA/cm2, and a spectrum having a light efficiency of 1.83 Im/W.
[252]
Industrial Applicability
[253] The compound of the present invention can be used as an organic material layer
material, particularly, hole injection and/or transport materials in an organic light
emitting device, and when applied to an organic light emitting device it is possible to
reduce the actuating voltage of the device, to improve the light efficiency thereof, and
to improve the lifespan of the device through ihe thermal stability of the compound.

Claims
An organic light emitting device, comprising:
a first electrode;
organic material layer(s) comprising a light emitting layer, wherein at least one
layer of the organic material layer(s) includes the compound of Formula 1 or a
compound of Formula 1 into which a thermosetting or photo-crosslinkable
functional group is introduced; and
a second electrode;
wherein the first electrode, the organic material layer(s), and the second electrode
form layered structure.
(Figure Removed)
wherein X is C or Si;
A is NZ1Z2:
B is NZ3Z4;
Y is a bond; bivalent aromatic hydrocarbons; bivalent aromatic hydrocarbons
which are substituted with at least one substituent group selected from the group
consisting of nitro, nitrile, halogen, alkyl, alkoxy, and amino groups: a bivalent
heterocyclic group; or a bivalent heterocyclic group which is substituted with at
least one substituent group selected from the group consisting of nitro, nitrile.
halogen, alkyl. alkoxy, and amino groups:
Zl to Z4 are each independently hydrogen: aliphatic hydrocarbons having a
carbon number of 1 - 20; aromatic hydrocarbons; aromatic hydrocarbons which
are substituted with at least one substituent group selected from the group
consisting of nitro, nitrile, halogen, alkyl, alkoxy, amino, aromatic hydrocarbon,
and heterocyclic groups; a silicon group substituted with aromatic hydrocarbons;
a heterocyclic group: a heterocyclic group which is substituted with at least one
substituent group selected from the group consisting of nitro, nitrile, halogen,
alkyl, alkoxy, amino, aromatic hydrocarbon, and heterocyclic groups; a
thiophenyl group which is substituted with hydrocarbons having a carbon
number of 1 - 20 or aromatic hydrocarbons having a carbon number of 6 - 20; or
a boron group which is substituted with aromatic hydrocarbons;
Rl to Rl 1 are each independently hydrogen, a substituted or unsubstituted alkyl
group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted
alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted
arylamine group, a substituted or unsubstituted heterocyclic group, an
amino group, a nitrile group, a nitro group, a halogen group, an amide group, or
an ester group, and Rl to Rl 1 may form aliphatic or hetero condensation rings
along with adjacent groups; and
R7 and R8 may be directly connected to each other, or may form a condensation
ring along with a group selected from the group consisting of O, S, NR, PR,
C=O, CRR1, and SiRR', wherein R and R' are each independently or collectively
are hydrogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted
alkoxy group, a substituted or unsubstituted alkenyl group, a
substituted or unsubstituted aryl group, a substituted or unsubstituted arylamine
group, a substituted or unsubstituted heterocyclic group, a nitrile group, an amide
group, or an ester group, and may form a condensation ring to form a spiro ..
compound.
[2] The organic light emitting device as set forth in claim 1, wherein R7 and RS of
Formula 1 form the condensation ring along with a group selected from the
group consisting of O, S, NR, PR, C=O, CRR', and SiRR' (R and R' being as
defined in Formula 1).
[3] The organic light emitting device as set forth in claim 1, wherein the compound
of Formula 1 is any one of compounds of Formulae 2 to 5:
R4
[Farwila 2] [Formula 3]
[.Formula 4] [Formula 5]
in the Formulae 2lo5,A. and B are as defined in claim 1.
The organic light emitting device as set forth in claim 1, wherein A and B of
Formula 1 are each independently any one of following groups:
(Figure Removed)
The organic light emitting device as set forth in claim 1, wherein the organic
material layer(s) comprise a hole injection layer, and the hole injection layer
includes the compound of Formula 1 or the compound of Formula 1 into which a
thermosetting or photo-cross linkable functional group is introduced.
The organic light emitting device as set forth in claim 1, wherein the organic
material layer(s) comprise a hole transport layer, and the hole transport layer
includes the compound of Formula ] or the compound of Formula 1 into which a
thermosefting or photo-cross linkable functional group is introduced.
The organic light emitting device as set forth in claim 1, wherein the organic
material layer(s) comprise a layer which both injects and transports holes and
which includes the compound of Formula 1 or the compound of Formula 1 into
which a thermosetting or photo-crosslinkable functional group is introduced.
The organic light emitting device as set forth in claim 1, comprising a homopolymer
or a copolymer of the compound of Formula 1.