KR102170390B1 - Multicyclic compound and organic light emitting device comprising the same - Google Patents

Abstract

The present specification relates to a compound of Formula 1 and an organic light emitting device including the same.

Description

A polycyclic compound and an organic light-emitting device including the same TECHNICAL FIELD

This application claims the benefit of the filing date of Korean Patent Application No. 10-2018-0086619 filed with the Korean Intellectual Property Office on July 25, 2018, the entire contents of which are incorporated herein.

The present specification relates to a polycyclic compound and an organic light emitting device including the same.

In the present specification, an organic light-emitting device is a light-emitting device using an organic semiconductor material, and requires an exchange of holes and/or electrons between an electrode and an organic semiconductor material. The organic light emitting device can be divided into two types as follows according to the operating principle. First, excitons are formed in the organic material layer by photons introduced into the device from an external light source, and the excitons are separated into electrons and holes, and these electrons and holes are transferred to different electrodes, and used as a current source (voltage source). It is a type of light emitting device. The second is a light emitting device in which holes and/or electrons are injected into an organic semiconductor material layer that forms an interface with the electrode by applying voltage or current to two or more electrodes, and operates by the injected electrons and holes.

In general, the organic light emission phenomenon refers to a phenomenon in which electrical energy is converted into light energy using an organic material. An organic light emitting device using the organic light emitting phenomenon has a structure including an anode, a cathode, and an organic material layer therebetween. Here, the organic material layer is often made of a multilayer structure composed of different materials in order to increase the efficiency and stability of the organic light emitting device.For example, the organic material layer is composed of a hole injection layer, a hole transport layer, a light emitting layer, an electron suppression layer, an electron transport layer, an electron injection layer, etc. I can lose. In the structure of such an organic light-emitting device, when a voltage is applied between the two electrodes, holes are injected from the anode and electrons from the cathode are injected into the organic material layer, and excitons are formed when the injected holes and electrons meet. It glows when it falls back to the ground. These organic light emitting devices are known to have characteristics such as self-luminescence, high brightness, high efficiency, low driving voltage, wide viewing angle, and high contrast.

Materials used as the organic material layer in the organic light-emitting device may be classified into light-emitting materials and charge transport materials, such as hole injection materials, hole transport materials, electron suppression materials, electron transport materials, electron injection materials, and the like, according to their functions. The light-emitting material includes blue, green, and red light-emitting materials and yellow and orange light-emitting materials necessary to realize better natural colors according to the light-emitting color.

In addition, in order to increase color purity and increase luminous efficiency through energy transfer, a host/dopant system may be used as a light emitting material. The principle is that when a small amount of a dopant having an energy band gap smaller than that of a host that mainly constitutes the light emitting layer is mixed with the light emitting layer, excitons generated from the host are transported as a dopant to emit light with high efficiency. At this time, since the wavelength of the host moves to the wavelength of the dopant, light having a desired wavelength can be obtained according to the type of dopant used.

In order to fully exhibit the excellent characteristics of the organic light emitting device described above, materials that form the organic material layer in the device, such as hole injection materials, hole transport materials, light-emitting materials, electron suppression materials, electron transport materials, electron injection materials, etc., are stable and efficient materials. As it is supported by, the development of new materials is continuously required.

Korea Public Publication No. 2016-064956

In the present specification, a compound and an organic light emitting device including the same are described.

An exemplary embodiment of the present specification provides a compound represented by Formula 1 below.

[Formula 1]

In Formula 1,

X is hydrogen; Cyano group; A substituted or unsubstituted phenyl group; Or a substituted or unsubstituted biphenyl group,

Any one of A and B is a carbazole group substituted with a cyano group, and the other is a substituted or unsubstituted dibenzofuran group; Or a substituted or unsubstituted dibenzothiophene group.

Further, according to an exemplary embodiment of the present invention, the first electrode; A second electrode provided to face the first electrode; And one or more organic material layers provided between the first electrode and the second electrode, wherein at least one of the organic material layers includes the aforementioned compound.

The compound of the present invention can be used as a material for an organic material layer of an organic light emitting device. In the case of manufacturing an organic light-emitting device including the compound of the present invention, an organic light-emitting device having high efficiency, low voltage, and long lifespan characteristics can be obtained, and when the compound of the present invention is included in the emission layer of the organic light-emitting device, the voltage increases during driving It is possible to manufacture an organic light-emitting device having a long life and suppression.

Specifically, by introducing the substituents to Nos. 2 and 6 of the dibenzothiophene skeleton, it is possible to achieve both high luminous efficiency and long life, and further significantly lower the driving voltage of the device compared to the conventional compound. This effect is exhibited because a carbazole group substituted with a cyano group, a substituted or unsubstituted dibenzofuran group, or a substituted or unsubstituted dibenzothiophene group is positioned at the 6th position to increase steric hindrance. In other words, since the overall planarity of the molecule is lowered and a compound having a large steric hindrance becomes a compound, the interaction between the compounds is suppressed, so that energy transfer to the light emitting material is further improved. In addition, since a carbazole group substituted with a cyano group, a substituted or unsubstituted dibenzofuran group, or a substituted or unsubstituted dibenzothiophene group is located at position 2, Homo and LUMO are appropriately located, As the stability of the material is increased, there is a high efficiency and long life effect. Additionally, at the 4th position, hydrogen, cyano group, substituted or unsubstituted phenyl group, or substituted or unsubstituted biphenyl group is located, providing additional stability, which is advantageous in realizing high efficiency or long life.

1 is a substrate (1), an anode (2), a hole injection layer (3), a hole transport layer (4), an electron blocking layer (5), a light emitting layer (6), a hole blocking layer (7), an electron transport layer (8). , An electron injection layer 9, a cathode 10, and an example of an organic light-emitting device comprising the capsule 11 is shown.
2 shows an example of an organic light-emitting device comprising a substrate 1, an anode 2, a light-emitting layer 6, and a cathode 10.
3 shows mass spectral data of Compound 1.
4 shows mass spectral data of Compound 2.

Hereinafter, the present specification will be described in more detail.

The present specification provides a compound represented by the following formula (1). As the compound of Formula 1 below uses dibenzothiophene as a core structure, the lowest triplet energy is high and the glass transition temperature is high, so that when applied to a device, a device with a long life can be obtained. And a carbazole group substituted with a cyano group in any one of B, and a dibenzofuran group substituted or unsubstituted in the other one; Or by introducing a substituted or unsubstituted dibenzothiophene group, the π-π interaction is large through the dibenzofuran group and the dibenzothiophene group, and electron inhaling N-type characteristics are achieved through the cyano group (CN) substituent. As a result, since the electron injection and transport capability of the material is improved, an organic light-emitting device having a low driving voltage and excellent luminous efficiency can be obtained when applied to a device.

[Formula 1]

In Formula 1,

X is hydrogen; Cyano group; A substituted or unsubstituted phenyl group; Or a substituted or unsubstituted biphenyl group,

Any one of A and B is a carbazole group substituted with a cyano group, and the other is a substituted or unsubstituted dibenzofuran group; Or a substituted or unsubstituted dibenzothiophene group.

In the present specification, when a part "includes" a certain component, it means that other components may be further included rather than excluding other components unless otherwise stated.

In the present specification, when a member is said to be located "on" another member, this includes not only the case where the member is in contact with the other member, but also the case where another member exists between the two members.

Examples of the substituent in the present specification are described below, but are not limited thereto.

The term "substituted" means that the hydrogen atom bonded to the carbon atom of the compound is replaced with another substituent, and the position to be substituted is not limited as long as the position at which the hydrogen atom is substituted, that is, the position where the substituent can be substituted, and when two or more are substituted , Two or more substituents may be the same or different from each other.

In the present specification, the term "substituted or unsubstituted" refers to deuterium; Halogen group; Cyano group (-CN); Silyl group; Boron group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted aryl group; And a substituted or unsubstituted heterocyclic group, substituted with one or two or more substituents selected from the group consisting of, or two or more of the substituents exemplified above are substituted with a connected substituent, or no substituent. For example, "a substituent to which two or more substituents are connected" may be a biphenyl group. That is, the biphenyl group may be an aryl group, or may be interpreted as a substituent to which two phenyl groups are connected.

Examples of the substituents are described below, but are not limited thereto.

In the present specification, examples of the halogen group include fluorine (F), chlorine (Cl), bromine (Br), or iodine (I).

In the present specification, the silyl group may be represented by the formula of -SiYaYbYc, wherein Ya, Yb and Yc are each hydrogen; A substituted or unsubstituted alkyl group; Or it may be a substituted or unsubstituted aryl group. Specifically, the silyl group includes trimethylsilyl group, triethylsilyl group, tert-butyldimethylsilyl group, vinyldimethylsilyl group, propyldimethylsilyl group, triphenylsilyl group, diphenylsilyl group, phenylsilyl group, etc. Does not.

In the present specification, the boron group may be represented by the formula of -BY4Y5, wherein Y4 and Y5 are each hydrogen; A substituted or unsubstituted alkyl group; Or it may be a substituted or unsubstituted aryl group. Specifically, the boron group includes a trimethyl boron group, a triethyl boron group, a tert-butyldimethyl boron group, a triphenyl boron group, and a phenyl boron group, but is not limited thereto.

In the present specification, the alkyl group may be a linear or branched chain, and the number of carbon atoms is not particularly limited, but is preferably 1 to 60. According to an exemplary embodiment, the alkyl group has 1 to 30 carbon atoms. According to another exemplary embodiment, the alkyl group has 1 to 20 carbon atoms. According to another exemplary embodiment, the alkyl group has 1 to 10 carbon atoms. Specific examples of the alkyl group include, but are not limited to, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and the like.

In the present specification, the number of carbon atoms of the alkoxy group is not particularly limited, but is preferably 1 to 60. According to an exemplary embodiment, the alkoxy group has 1 to 30 carbon atoms. According to another exemplary embodiment, the alkoxy group has 1 to 20 carbon atoms. According to another exemplary embodiment, the alkoxy group has 1 to 10 carbon atoms. Specific examples of the alkoxy group include, but are not limited to, a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.

In the present specification, the cycloalkyl group is not particularly limited, but is preferably 3 to 60 carbon atoms, and according to an exemplary embodiment, the cycloalkyl group has 3 to 30 carbon atoms. According to another exemplary embodiment, the number of carbon atoms of the cycloalkyl group is 3 to 20. According to another exemplary embodiment, the cycloalkyl group has 3 to 6 carbon atoms. Specifically, there are a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and the like, but are not limited thereto.

In the present specification, the aryl group is not particularly limited, but is preferably 6 to 60 carbon atoms, and may be a monocyclic aryl group or a polycyclic aryl group. According to an exemplary embodiment, the aryl group has 6 to 30 carbon atoms. According to an exemplary embodiment, the aryl group has 6 to 20 carbon atoms. The aryl group may be a phenyl group, a biphenyl group, or a terphenyl group, but the monocyclic aryl group is not limited thereto. The polycyclic aryl group may be a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, a perylenyl group, a triphenyl group, a chrysenyl group, a fluorenyl group, and the like, but is not limited thereto.

In the present specification, the fluorenyl group may be substituted, and two substituents may be bonded to each other to form a spiro structure.

,

등의 스피로플루오레닐기,

(9,9-디메틸플루오레닐기), 및

(9,9-디페닐플루오레닐기) 등의 치환된 플루오레닐기가 될 수 있다. 다만, 이에 한정되는 것은 아니다.When the fluorenyl group is substituted,

,

Spirofluorenyl groups such as,

(9,9-dimethylfluorenyl group), and

It may be a substituted fluorenyl group such as (9,9-diphenylfluorenyl group). However, it is not limited thereto.

In the present specification, the heterocyclic group is a cyclic group including at least one of N, O, S, and Se as a hetero atom, and the number of carbons is not particularly limited, but is preferably 2 to 60 carbon atoms. According to an exemplary embodiment, the number of carbon atoms of the heterocyclic group is 2 to 30. Examples of the heterocyclic group include a pyridine group, a pyrrole group, a pyrimidine group, a pyridazinyl group, a furan group, a thiophene group, an imidazole group, a pyrazole group, a dibenzofuran group, a dibenzothiophene group, and a carbazole group. However, it is not limited to these.

In the exemplary embodiment of the present specification, X is hydrogen; Cyano group; A phenyl group unsubstituted or substituted with deuterium; Or a biphenyl group unsubstituted or substituted with deuterium.

According to an exemplary embodiment of the present specification, X is hydrogen; Cyano group; A phenyl group unsubstituted or substituted with deuterium; Or a biphenyl group.

In the exemplary embodiment of the present specification, any one of A and B is a carbazole group substituted with a cyano group, and the other is a cyano group, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 30 carbon atoms substituted or unsubstituted Dibenzofuran group; Or a dibenzothiophene group unsubstituted or substituted with a cyano group, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 30 carbon atoms.

According to another exemplary embodiment, any one of A and B is a carbazole group substituted with a cyano group, and the other is a dibenzofuran group unsubstituted or substituted with a cyano group, a butyl group, or a phenyl group; Or a cyano group, a butyl group, or a dibenzothiophene group unsubstituted or substituted with a phenyl group.

In the exemplary embodiment of the present specification, any one of A and B is a carbazole group substituted with a cyano group, and the other is a dibenzofuran group unsubstituted or substituted with a cyano group, tert-butyl group, or phenyl group; Or a cyano group, a tert-butyl group, or a dibenzothiophene group unsubstituted or substituted with a phenyl group.

According to an exemplary embodiment of the present specification, A is a carbazole group substituted with a cyano group, and B is a dibenzofuran group unsubstituted or substituted with a cyano group, tert-butyl group, or phenyl group.

According to an exemplary embodiment of the present specification, B is a carbazole group substituted with a cyano group, and A is a dibenzofuran group unsubstituted or substituted with a cyano group, tert-butyl group, or phenyl group.

According to an exemplary embodiment of the present specification, A is a carbazole group substituted with a cyano group, and B is a dibenzothiophene group unsubstituted or substituted with a cyano group, tert-butyl group, or phenyl group.

According to an exemplary embodiment of the present specification, B is a carbazole group substituted with a cyano group, and A is a dibenzothiophene group unsubstituted or substituted with a cyano group, tert-butyl group, or phenyl group.

According to an exemplary embodiment of the present specification, any one of A and B is a carbazole group substituted with a cyano group, and the other is represented by the following structural formula.

는 디벤조티오펜에 결합되는 위치를 의미한다.In the above structural formula, R1 is the same as the definition in Formula 2,

Means a position bonded to dibenzothiophene.

또는

이고, 나머지 하나는 하기 구조식으로 표시된다.According to an exemplary embodiment of the present specification, any one of A and B is

or

And the other one is represented by the following structural formula.

는 디벤조티오펜에 결합되는 위치를 의미한다.In the above structural formula, R2 is the same as the definition in Formula 2,

Means a position bonded to dibenzothiophene.

In an exemplary embodiment of the present specification, the compound represented by Formula 1 is represented by the following Formula 2 or 3.

[Formula 2]

[Formula 3]

In Formulas 2 and 3,

The definition of X is as defined in Formula 1,

X1 is O or S,

R1 and R2 are the same as or different from each other, and each independently hydrogen; heavy hydrogen; Halogen group; Cyano group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group,

n1 and n2 are integers of 0 to 7, and when n1 and n2 are each 2 or more, the substituents in the parentheses of 2 or more are the same or different from each other.

According to an exemplary embodiment of the present specification, R1 and R2 are the same as or different from each other, and each independently hydrogen; heavy hydrogen; Halogen group; Cyano group; A substituted or unsubstituted C1 to C20 alkyl group; A substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms; A substituted or unsubstituted C3 to C30 cycloalkyl group; A substituted or unsubstituted aryl group having 6 to 60 carbon atoms; Or a substituted or unsubstituted C2 to C60 heterocyclic group.

According to another exemplary embodiment, the R1 and R2 are the same as or different from each other, and each independently hydrogen; heavy hydrogen; Halogen group; Cyano group; A substituted or unsubstituted C1 to C20 alkyl group; A substituted or unsubstituted aryl group having 6 to 30 carbon atoms; Or a substituted or unsubstituted C2 to C30 heterocyclic group.

In another exemplary embodiment, R1 and R2 are the same as or different from each other, and each independently hydrogen; heavy hydrogen; Cyano group; An alkyl group having 1 to 20 carbon atoms; Or an aryl group having 6 to 30 carbon atoms.

According to another exemplary embodiment, R1 and R2 are hydrogen; heavy hydrogen; Cyano group; Butyl group; Or a phenyl group.

According to another exemplary embodiment, R1 is hydrogen; Cyano group; t-butyl group; Or a phenyl group.

According to another exemplary embodiment, R2 is hydrogen.

According to an exemplary embodiment of the present specification, n1 and n2 are 0 or 1, respectively.

In the exemplary embodiment of the present specification, Chemical Formula 1 may be represented by any one of the following structures.

In the exemplary embodiment of the present specification, the lowest triplet (triplet, E _T ) energy level of the compound represented by Formula 1 is 2.7 eV or more.

In the exemplary embodiment of the present specification, the lowest triplet energy level of the compound represented by Formula 1 is 2.7 eV or more and 3.0 eV or less, and preferably 2.7 eV or more and 2.9 eV or less. When the lowest triplet energy level satisfies the above range, excellent luminous efficiency is exhibited when applied to a device. Specifically, according to an exemplary embodiment of the present invention, when the compound is used as a host of the light emitting layer and the lowest triplet energy level satisfies the above range, energy transfer to the dopant material used together is smooth. Is achieved, and the transferred energy can be prevented from being reversed to the host.

The triplet energy E _T can be obtained as follows by connecting a temperature control device PMU-830 to a JASCO FP-8600 fluorescence spectrophotometer measuring device. In order to obtain singlet energy, a quartz cell containing the prepared oxygen-removed sample solution is placed in a device containing liquid nitrogen (N ₂ ). After temperature stabilization (77K), the phosphorescence spectrum is measured. At this time, in the phosphorescence spectrum, the x-axis is the wavelength (λ, unit: nm) and the y-axis is the luminance. When a tangent line descending from the maximum emission peak at the longest wavelength to the short wavelength direction is drawn, the intersection of the tangent line and the x-axis is Obtain the wavelength value (nm). The value obtained by converting this wavelength value (nm) into an energy value (eV) is the triplet energy level E _T (eV), which represents the lowest triplet energy level value.

In an exemplary embodiment of the present specification, the glass transition temperature of the compound represented by Formula 1 is 120°C or higher.

In the exemplary embodiment of the present specification, the glass transition temperature of the compound represented by Formula 1 is 120°C or more and 200°C or less. When the glass transition temperature of the compound represented by Chemical Formula 1 satisfies the above range, high purity can be achieved by a sublimation purification method in the synthesis process, and when manufacturing an organic light-emitting device containing the compound, It has the advantage of not being contaminated, and since crystallization and agglomeration of the material does not occur, it is possible to achieve a long life of the device.

In an exemplary embodiment of the present specification, the glass transition temperature (Tg) of the compound represented by Formula 1 can be confirmed through calorie measurement according to temperature increase or decrease using DSC (Differential Scanning Colorimetry). have.

The compound represented by Chemical Formula 1 according to an exemplary embodiment of the present specification may have a core structure manufactured in the same manner as in the reaction scheme described below.

For example, the compound of Formula 1 may have a core structure as shown in the following scheme. Substituents may be bonded by methods known in the art, and the type, position, or number of substituents may be changed according to techniques known in the art.

<Reaction Scheme>

The core structure of Formula 1 of the present invention can be prepared by reacting 4-iodo-dibenzothiophene with an excess of bromine. Specifically, in the structure of Formula 1, a substituent B may be introduced into the core structure through a Suzuki reaction, and a substituent A may be introduced through a Buchwald reaction or an Ullmann reaction, and then, boronic acid is introduced, Substituent X can be introduced through Suzuki reaction.

The conjugation length and energy band gap of a compound are closely related. Specifically, the longer the conjugation length of the compound, the smaller the energy band gap.

In the present invention, compounds having various energy band gaps can be synthesized by introducing various substituents into the core structure as described above. In addition, in the present invention, the HOMO and LUMO energy levels of the compound can be adjusted by introducing various substituents to the core structure of the above structure.

In addition, by introducing various substituents into the core structure of the above-described structure, a compound having the inherent characteristics of the introduced substituent can be synthesized. For example, by introducing a substituent mainly used for the hole injection layer material, the hole transport material, the light emitting layer material and the electron transport layer material used in the manufacture of the organic light emitting device into the core structure, it is possible to synthesize a material that satisfies the conditions required by each organic material layer. I can.

In addition, the organic light emitting device according to the present invention includes a first electrode; A second electrode provided to face the first electrode; And one or more organic material layers provided between the first electrode and the second electrode, wherein at least one of the organic material layers includes the above-described compound.

The organic light-emitting device of the present invention may be manufactured by a conventional method and material of an organic light-emitting device, except that one or more organic material layers are formed by using the above-described compound.

The compound may be formed as an organic material layer by a solution coating method as well as a vacuum deposition method when manufacturing an organic light emitting device. Here, the solution coating method refers to spin coating, dip coating, inkjet printing, screen printing, spray method, roll coating, and the like, but is not limited thereto.

The organic material layer of the organic light emitting device of the present invention may have a single-layer structure, but may have a multilayer structure in which two or more organic material layers are stacked. For example, the organic light-emitting device of the present invention may have a structure including a hole injection layer, a hole transport layer, a layer that simultaneously injects and transports holes, a light emitting layer, an electron transport layer, an electron injection layer, and the like as an organic material layer. However, the structure of the organic light emitting device is not limited thereto, and may include a smaller number of organic material layers or a greater number of organic material layers.

In the organic light emitting device of the present invention, the organic material layer may include at least one of an electron transport layer, an electron injection layer, and a layer that simultaneously injects and transports electrons, and at least one of the layers is represented by Formula 1 above. It may contain a compound.

In another organic light emitting device, the organic material layer may include an electron transport layer or an electron injection layer, and the electron transport layer or the electron injection layer may include a compound represented by Formula 1 above.

In the organic light emitting device of the present invention, the organic material layer may include at least one of a hole injection layer, a hole transport layer, and a layer that simultaneously injects and transports holes, and at least one of the layers is represented by Formula 1 above. It may contain a compound.

In another organic light emitting device, the organic material layer may include a hole injection layer or a hole transport layer, and the hole transport layer or the hole injection layer may include a compound represented by Formula 1 above.

In another exemplary embodiment, the organic material layer includes an emission layer, and the emission layer includes a compound represented by Formula 1 above. As an example, the compound represented by Formula 1 may be included as a host of the emission layer.

In the exemplary embodiment of the present specification, the organic light-emitting device is a green organic light-emitting device in which the emission layer includes the compound represented by Formula 1 as a host.

According to the exemplary embodiment of the present specification, the organic light-emitting device is a red organic light-emitting device in which the emission layer includes the compound represented by Formula 1 as a host.

In another exemplary embodiment, the organic light-emitting device is a blue organic light-emitting device in which the emission layer includes the compound represented by Formula 1 as a host.

As another example, the light emitting layer including the compound represented by Formula 1 may include the compound represented by Formula 1 as a host, and may further include a dopant.

As another example, the light emitting layer including the compound represented by Formula 1 may include the compound represented by Formula 1 as a host, and may further include a thermally activated delayed fluorescence dopant (TADF). .

According to the exemplary embodiment of the present specification, the emission layer of the organic light-emitting device may include the compound represented by Formula 1 as a host of the emission layer, and may further include a thermally activated delayed fluorescent dopant. The triplet energy level difference between the host and the thermally activated delayed fluorescent dopant (the triplet energy of the host-the thermally activated delayed fluorescent dopant triplet energy) may be 0.1 eV or more and 0.6 eV or less, preferably 0.2 eV or more and 0.6 eV or less, If the above range is satisfied, there is an advantage that a long life of the device can be realized.

In addition, as described above, it is preferable that the triplet energy of the host of the light emitting layer is higher than the triplet energy of the thermally activated delayed fluorescent dopant, and in this case, there is an advantage that the thermally activated delayed fluorescent dopant material is not quenched.

In addition, the thermally activated delayed fluorescent dopant of the light emitting layer may have a triplet energy level-a singlet energy level (T1-S1, ΔE _ST ) of 0.3 eV or less, more preferably 0 eV or more and 0.2 eV or less. When the ΔE _ST value satisfies the above range, delayed fluorescence can be used as a highly efficient light emitting material whose internal quantum efficiency can exceed 25%, which is a limit value of a fluorescent dopant material. Fluorescence is usually completed within a short time of 100 ns or less, but fluorescence that continues to emit light for a time period of much longer μs or longer is called delayed fluorescence. There are P-type and E-type for delayed fluorescence according to the luminescence mechanism.

Since the P-type delayed fluorescence is generated through triplet-triplet annihilation (TTA), 100% internal quantum efficiency cannot be achieved, but the E-type delayed fluorescence is activated by thermal energy. It is known as thermally activated delayed fluorescence. According to the E-type delayed fluorescence, when the energy difference between the singlet exciton state and the triplet exciton state (ΔE _ST ) is small, preferably less than 0.2 eV, the singlet excitons emit light as they are ( That is, fluorescence) and triplet excitons are reverse-intersystem crossing with singlet excitons to emit light (that is, delayed fluorescence). Therefore, in the E-type delayed fluorescence, since the emission by the delayed fluorescence mechanism is added to the emission by the fluorescence mechanism, it is possible to increase the internal quantum efficiency up to 100%.

The measurement equipment used to measure the triplet energy-singlet energy level (ΔE _ST ) is a JASCO FP-8600 fluorescence spectrophotometer.

The singlet energy E _s can be obtained as follows. A sample for measurement is prepared by dissolving the compound to be measured at a concentration of 1 μM using toluene as a solvent. The sample solution is placed in a quartz cell, degassed using nitrogen gas (N ₂ ) to remove oxygen in the solution, and then the absorption spectrum is measured at room temperature (300K) using a measuring device. At this time, the absorption spectrum is the wavelength (λ, unit: nm) on the x-axis and absorbance on the y-axis, and draw a tangent from the maximum absorption peak at the longest wavelength to the long wavelength direction, and the wavelength value of the point where the tangent line meets the x-axis ( nm). The value obtained by converting this wavelength value (nm) into an energy value (eV) is taken as singlet energy E _S (eV). The triplet energy E _T can be measured as described above, and △E _ST is defined as the absolute value of the difference between E _S (eV) and E _T (eV), and can be obtained by the difference between the measured values above. have.

According to an exemplary embodiment of the present specification, the compound represented by Formula 1 may be used as a host material for a light emitting layer used together with the thermally delayed fluorescent dopant material, and as described above, the triplet energy level difference between the host and the dopant It has a long-life, high-efficiency device can be manufactured.

The maximum emission peak of the thermally activated delayed fluorescent dopant of the emission layer is 450 nm to 550 nm. The maximum emission peak was measured using the LS-55 of Perkin Elmer, and the emission spectrum at an excitation wavelength of 350 nm was 400 nm to 680 nm, and HPLC grade THF was used as a solvent.

In the exemplary embodiment of the present specification, the half-value width of the emission band of the maximum emission wavelength in the emission spectrum of the dopant of the emission layer is 50 nm or more and 100 nm or less. When the half-value width satisfies the above range, it is possible to extend the life of the device.

According to the exemplary embodiment of the present specification, the thermally activated delayed fluorescent dopant of the emission layer may be selected from Formulas 10 or 11, but is not limited thereto.

[Formula 10]

In Formula 10,

W1 is a cyano group,

A plurality of W2 is the same as or different from each other, and each independently a substituted or unsubstituted carbazole group; Or a substituted or unsubstituted benzocarbazole group,

[Formula 11]

In Formula 11,

Y1 to Y3 are each N or CH, and at least one of Y1 to Y3 is N,

L is a direct bond; Or a substituted or unsubstituted arylene group,

Ar1 and Ar2 are the same as or different from each other, and each independently a substituted or unsubstituted aryl group,

Ar3 is a substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group, or combined with an adjacent group to form a substituted or unsubstituted ring,

m2 is an integer of 0 to 8, and when m2 is 2 or more, a plurality of Ar3s are the same or different from each other.

According to an exemplary embodiment of the present specification, the four W2 are the same as or different from each other, and each independently a substituted or unsubstituted carbazole group; Or a substituted or unsubstituted benzocarbazole group.

According to another exemplary embodiment, the four W2 are the same as or different from each other, and each independently a halogen group, a cyano group, an alkyl group having 1 to 20 carbon atoms, a fluoroalkyl group having 1 to 20 carbon atoms, and having 1 to 20 carbon atoms. A carbazole group unsubstituted or substituted with an alkoxy group or an aryl group having 6 to 30 carbon atoms; Or a benzocarbazole group unsubstituted or substituted with deuterium, a halogen group, a cyano group, an alkyl group having 1 to 20 carbon atoms, a fluoroalkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an aryl group having 6 to 30 carbon atoms. .

In another exemplary embodiment, the four W2 are the same as or different from each other, and each independently deuterium, fluorine, cyano group, methyl group, propyl group, trifluoromethyl group, methoxy group, or phenyl group substituted or unsubstituted Carbazole; Or a benzocarbazole group.

According to an exemplary embodiment of the present specification, Y1 to Y3 are N.

According to an exemplary embodiment of the present specification, L is a direct bond; Or a substituted or unsubstituted C 6 to C 30 arylene group.

In another exemplary embodiment, L is a direct bond; Or a phenylene group having 6 to 30 carbon atoms substituted or unsubstituted with a cyano group.

According to another exemplary embodiment, L is a direct bond; Or a phenylene group unsubstituted or substituted with a cyano group.

According to an exemplary embodiment of the present specification, Ar3 is a substituted or unsubstituted aryl group having 6 to 30 carbon atoms; Or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms, or combined with an adjacent group to form a substituted or unsubstituted ring.

In the exemplary embodiment of the present specification, m2 is an integer of 0 to 8, and when m2 is 2 or more, a plurality of Ar3 may be the same as or different from each other, and may be bonded to each other to form a substituted or unsubstituted ring.

According to another exemplary embodiment, Ar3 is a carbazole group or dibenzothiophene group substituted with a phenyl group, or indene substituted or unsubstituted by bonding with an adjacent group to each other; Substituted or unsubstituted indole; Or to form a substituted or unsubstituted benzothiophene.

According to an exemplary embodiment of the present specification, Formula 10 or 11 may be selected from the following compounds, but is not limited thereto.

As another example, the organic material layer including the compound represented by Formula 1 may include the compound represented by Formula 1 as a dopant, and may include a fluorescent host or a phosphorescent host.

In another exemplary embodiment, the organic material layer including the compound represented by Formula 1 includes the compound represented by Formula 1 as a dopant, includes a fluorescent host or phosphorescent host, and other organic compounds, metals, or metal compounds May be included as a dopant.

As another example, the organic material layer including the compound represented by Formula 1 includes the compound represented by Formula 1 as a dopant, includes a fluorescent host or a phosphorescent host, and can be used together with an iridium-based (Ir) dopant. have.

In the exemplary embodiment of the present specification, the first electrode is an anode, and the second electrode is a cathode.

According to another exemplary embodiment, the first electrode is a cathode, and the second electrode is an anode.

(1) Anode/Hole Transport Layer/Light-Emitting Layer/Anode

(2) Anode/Hole injection layer/Hole transport layer/Light emitting layer/Anode

(3) Anode/hole injection layer/hole buffer layer/hole transport layer/light emitting layer/cathode

(4) Anode/hole transport layer/light-emitting layer/electron transport layer/cathode

(5) Anode/hole transport layer/light-emitting layer/electron transport layer/electron injection layer/cathode

(6) Anode/hole injection layer/hole transport layer/light-emitting layer/electron transport layer/cathode

(7) Anode/hole injection layer/hole transport layer/light-emitting layer/electron transport layer/electron injection layer/cathode

(8) Anode/Hole injection layer/Hole buffer layer/Hole transport layer/Light emitting layer/Electron transport layer/Anode

(9) Anode/Hole injection layer/Hole buffer layer/Hole transport layer/Light emitting layer/Electron transport layer/Electron injection layer/Anode

(10) Anode/hole transport layer/electron suppression layer/light-emitting layer/electron transport layer/cathode

(11) Anode/hole transport layer/electron suppression layer/light emitting layer/electron transport layer/electron injection layer/cathode

(12) Anode/Hole injection layer/Hole transport layer/Electron suppression layer/Light-emitting layer/Electron transport layer/Anode

(13) Anode/hole injection layer/hole transport layer/electron suppression layer/light-emitting layer/electron transport layer/electron injection layer/cathode

(14) Anode/Hole Transport Layer/Light-Emitting Layer/Hole Suppression Layer/Electron Transport Layer/Anode

(15) Anode/Hole Transport Layer/Light-Emitting Layer/Hole Suppression Layer/Electron Transport Layer/Electron Injection Layer/Anode

(16) Anode/Hole Injection Layer/Hole Transport Layer/Light-Emitting Layer/Hole Suppression Layer/Electron Transport Layer/Anode

(17) Anode/Hole injection layer/Hole transport layer/Light emitting layer/Hole suppression layer/Electron transport layer/Electron injection layer/Anode

(18) Anode/Hole injection layer/Hole transport layer/Electron suppression layer/Light-emitting layer/Hole blocking layer/Electron injection and transport layer/Anode

The structure of the organic light-emitting device of the present invention may have a structure as shown in FIG. 1, but is not limited thereto.

The structure of the organic light-emitting device of the present invention may have a structure as shown in FIGS. 1 and 2, but is not limited thereto.

In Fig. 1, a substrate 1, an anode 2, a hole injection layer 3, a hole transport layer 4, an electron blocking layer 5, a light emitting layer 6, a hole blocking layer 7, an electron transport layer 8 , The structure of an organic light emitting device in which the electron injection layer 9, the cathode 10, and the capsule 11 are sequentially stacked is illustrated. In such a structure, the compound represented by Formula 1 is the hole injection layer (3), the hole transport layer (4), the electron blocking layer (5), the light emitting layer (6), the hole blocking layer (7), the electron transport layer ( 8) Or may be included in the electron injection layer (9).

FIG. 2 illustrates a structure of an organic light emitting diode in which an anode 2, a light emitting layer 6, and a cathode 10 are sequentially stacked on a substrate 1. In such a structure, the compound represented by Formula 1 may be included in the emission layer 6.

For example, the organic light-emitting device according to the present invention uses a PVD (physical vapor deposition) method such as sputtering or e-beam evaporation, and uses a metal or conductive metal oxide or alloy thereof on a substrate. From the group consisting of a hole injection layer, a hole transport layer, a layer for simultaneous hole transport and hole injection, a light-emitting layer, an electron transport layer, an electron injection layer, and a layer for simultaneously electron transport and electron injection. After forming an organic material layer including one or more selected layers, it can be prepared by depositing a material that can be used as a cathode thereon. In addition to this method, an organic light-emitting device may be manufactured by sequentially depositing a cathode material, an organic material layer, and an anode material on a substrate.

The organic material layer may have a multilayer structure including a hole injection layer, a hole transport layer, an emission layer, an electron transport layer, etc., but is not limited thereto and may have a single layer structure. In addition, the organic material layer is made of a variety of polymer materials, and is used in a smaller number of solvent processes, such as spin coating, dip coating, doctor blading, screen printing, inkjet printing, or thermal transfer. It can be made in layers.

The anode is an electrode for injecting holes, and a material having a large work function is preferable so that holes can be smoothly injected into the organic material layer as the anode material. Specific examples of the cathode material that can be used in the present invention include metals such as vanadium, chromium, copper, zinc, and gold, or alloys thereof; Metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); ZnO: Al or SnO _2: a combination of a metal and an oxide such as Sb; Poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene] (PEDOT), conductive polymers such as polypyrrole and polyaniline, and the like, but are not limited thereto.

The cathode is an electrode for injecting electrons, and the cathode material is usually a material having a small work function to facilitate electron injection into the organic material layer. Specific examples of the negative electrode material include metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, and lead, or alloys thereof; There are multi-layered materials such as LiF/Al or LiO ₂ /Al, but are not limited thereto.

The hole injection layer is a layer that facilitates injection of holes from the anode to the light emitting layer, and the hole injection material is a material capable of receiving holes from the anode at a low voltage, and is a high occupied HOMO (highest occupied material) of the hole injection material. It is preferable that molecular orbital) is between the work function of the positive electrode material and the HOMO of the surrounding organic material layer. Specific examples of hole injection materials include metal porphyrine, oligothiophene, arylamine-based organic substances, hexanitrile hexaazatriphenylene-based organic substances, quinacridone-based organic substances, and perylene-based organic substances. Organic substances, anthraquinone, polyaniline, and polythiophene-based conductive polymers, etc., but are not limited thereto. The thickness of the hole injection layer may be 1 to 150 nm. When the thickness of the hole injection layer is 1 nm or more, there is an advantage of preventing deterioration of the hole injection characteristics, and when the thickness of the hole injection layer is 150 nm or less, the thickness of the hole injection layer is too thick to increase the driving voltage to improve the movement of holes. There is an advantage that can prevent it.

The hole transport layer may serve to facilitate transport of holes. As the hole transport material, a material capable of transporting holes from the anode or the hole injection layer and transferring them to the emission layer, and a material having high mobility for holes is suitable. Specific examples include an arylamine-based organic material, a conductive polymer, and a block copolymer including a conjugated portion and a non-conjugated portion, but are not limited thereto.

A hole buffer layer may be additionally provided between the hole injection layer and the hole transport layer, and may include a hole injection or transport material known in the art.

An electron suppressing layer may be provided between the hole transport layer and the light emitting layer. The electron suppressing layer may be formed of the above-described spiro compound or a material known in the art.

The emission layer may emit red, green, or blue light, and may be made of a phosphorescent material or a fluorescent material. The light-emitting material is a material capable of emitting light in a visible light region by transporting and bonding holes and electrons from the hole transport layer and the electron transport layer, respectively, and a material having good quantum efficiency for fluorescence or phosphorescence is preferable. Specific examples include 8-hydroxy-quinoline aluminum complex (Alq ₃ ); Carbazole-based compounds; Dimerized styryl compounds; BAlq; 10-hydroxybenzo quinoline-metal compound; Benzoxazole, benzthiazole, and benzimidazole-based compounds; Poly(p-phenylenevinylene) (PPV)-based polymer; Spiro compounds; Polyfluorene, rubrene, and the like, but are not limited thereto.

Examples of the host material for the light emitting layer include condensed aromatic ring derivatives or heterocyclic compounds. Specifically, condensed aromatic ring derivatives include anthracene derivatives, pyrene derivatives, naphthalene derivatives, pentacene derivatives, phenanthrene compounds, and fluoranthene compounds, and heterocycle-containing compounds include carbazole derivatives, dibenzofuran derivatives, ladder type Furan compounds, pyrimidine derivatives, and the like, but are not limited thereto.

When the emission layer emits red light, the emission dopants include PIQIr(acac)(bis(1-phenylisoquinoline)acetylacetonateiridium), PQIr(acac)(bis(1-phenylquinoline)acetylacetonate iridium), PQIr(tris(1-phenylquinoline)iridium). ), a phosphorescent material such as octaethylporphyrin platinum (PtOEP), or a fluorescent material such as Alq ₃ (tris(8-hydroxyquinolino)aluminum), but is not limited thereto. When the emission layer emits green light, a phosphor such as Ir(ppy) ₃ (fac tris(2-phenylpyridine)iridium) or a fluorescent material such as Alq3 (tris(8-hydroxyquinolino)aluminum) may be used as the emission dopant. However, it is not limited thereto. When the light emitting layer emits blue light, the light emitting dopant is a phosphorescent material such as (4,6-F2ppy) ₂ Irpic, spiro-DPVBi, spiro-6P, distillbenzene (DSB), distrylarylene (DSA), A fluorescent material such as a PFO-based polymer or a PPV-based polymer may be used, but is not limited thereto.

The electron transport layer may serve to facilitate transport of electrons. As the electron transport material, a material capable of receiving electrons from the cathode and transferring them to the light emitting layer, and a material having high mobility for electrons is suitable. Specific examples include Al complex of 8-hydroxyquinoline; Complexes containing Alq ₃ ; Organic radical compounds; Hydroxyflavone-metal complexes and the like, but are not limited thereto. The thickness of the electron transport layer may be 1 to 50 nm. If the thickness of the electron transport layer is 1 nm or more, there is an advantage of preventing deterioration of the electron transport characteristics, and if the thickness of the electron transport layer is 50 nm or less, the thickness of the electron transport layer is too thick to prevent an increase in the driving voltage to improve the movement of electrons. There is an advantage to be able to.

The electron injection layer may serve to facilitate injection of electrons. The electron injection material has the ability to transport electrons, has an electron injection effect from the cathode, an excellent electron injection effect for the light emitting layer or the light emitting material, prevents the movement of excitons generated in the light emitting layer to the hole injection layer, and , A compound having excellent thin film forming ability is preferred. Specifically, fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, preorenylidene methane, anthrone, and their derivatives, metals Complex compounds and nitrogen-containing 5-membered ring derivatives, but are not limited thereto.

Examples of the metal complex compound include lithium 8-hydroxyquinolinato, bis(8-hydroxyquinolinato)zinc, bis(8-hydroxyquinolinato)copper, bis(8-hydroxyquinolinato)manganese, Tris(8-hydroxyquinolinato)aluminum, tris(2-methyl-8-hydroxyquinolinato)aluminum, tris(8-hydroxyquinolinato)gallium, bis(10-hydroxybenzo[h] Quinolinato)beryllium, bis(10-hydroxybenzo[h]quinolinato)zinc, bis(2-methyl-8-quinolinato)chlorogallium, bis(2-methyl-8-quinolinato)( o-cresolato)gallium, bis(2-methyl-8-quinolinato)(1-naphtholato)aluminum, bis(2-methyl-8-quinolinato)(2-naphtholato)gallium, etc. It is not limited to this.

The hole suppression layer is a layer that prevents holes from reaching the cathode, and may be generally formed under the same conditions as the hole injection layer. Specifically, there are oxadiazole derivatives, triazole derivatives, phenanthroline derivatives, BCP, aluminum complexes, etc., but are not limited thereto.

The organic light emitting device according to the present invention may be a top emission type, a bottom emission type, or a double-sided emission type depending on the material used.

Hereinafter, in order to explain the present specification in detail, it will be described in detail with reference to examples. However, the embodiments according to the present specification may be modified in various forms, and the scope of the present application is not construed as being limited to the embodiments described below. The embodiments of the present application are provided to more completely describe the present specification to those of ordinary skill in the art.

<Synthesis Example>

Synthesis Example 1. Synthesis of Compound 1

1) Preparation of Intermediate A

2-bromo-6-iododibenzo[b,d]thiophene 38.9 g (0.1 mol), dibenzo[b,d]thiophen-4-yl-boronic acid 25.1 g (0.11 mol), Pd( PPh ₃ ) ₄ 5.8 g (0.005 mol), K ₂ CO ₃ 41.5 g (0.3 mol) were dissolved in tetrahydrofuran/distilled water 240 ml/80 ml, and then stirred under reflux under nitrogen conditions for 12 hours. After cooling to room temperature, ethyl acetate was added thereto, followed by extraction, and the organic layer was dried over MgSO ₄ and then the solvent was distilled off under reduced pressure. The reaction product was purified by column chromatography (CH ₃ Cl:Hex = 1:10), and recrystallized with ethanol to obtain 32.6 g of compound A. A peak was confirmed at M/Z=445 by measuring the mass spectrum of the obtained solid.

2) Preparation of compound 1

Intermediate A 13.4 g (0.03 mol), 9H-carbazole-3-carbonitrile 5.8 g (0.03 mol), CuI 5.7 g (0.03 mol), 1,10-phenanthroline (1,10-Phenanthroline) 8.7 g ( 0.048 mol), K ₃ PO ₄ 9.0 g (0.036 mol) was dissolved in xylene and stirred under reflux for 24 hours. After cooling to room temperature, chloroform and distilled water were added for extraction, and the organic layer was dried over MgSO ₄ , and the solvent was distilled off under reduced pressure. The reaction product was purified by column chromatography (CH ₃ Cl:Hex = 1:4), and recrystallized with ethanol to obtain 5.6 g of compound 1. A peak was confirmed at M/Z=557 by measurement of the mass spectrum of the obtained solid. Mass spectrum data of Compound 1 is shown in FIG. 3.

Synthesis Example 2. Synthesis of Compound 2

1) Preparation of Intermediate B

2-bromo-6-iododibenzo[b,d]thiophene 38.9 g (0.1 mol), dibenzo[b,d]furan-4-yl-boronic acid 23.3 g (0.11 mol), Pd(PPh ₃ ) ₄ 5.8 g (0.005 mol), K ₂ CO ₃ 41.5 g (0.3 mol) was dissolved in tetrahydrofuran/distilled water 240 ml/80 ml, and then stirred under reflux under nitrogen conditions for 12 hours. After cooling to room temperature, ethyl acetate was added thereto, followed by extraction, and the organic layer was dried over MgSO ₄ and then the solvent was distilled off under reduced pressure. The reaction product was purified by column chromatography (CH ₃ Cl:Hex = 1:10) and recrystallized with ethanol to obtain 30.6 g of compound B. A peak was confirmed at M/Z=429 by measuring the mass spectrum of the obtained solid.

2) Preparation of compound 2

Intermediate B 12.9 g (0.03 mol), 9H-carbazole-3-carbonitrile 5.8 g (0.03 mol), CuI 5.7 g (0.03 mol), 1,10-Phenanthroline 8.7 g (0.048 mol), K ₃ PO ₄ 9.0 After dissolving g (0.036 mol) in xylene, the mixture was stirred under reflux for 24 hours. After cooling to room temperature, chloroform and distilled water were added for extraction, and the organic layer was dried over MgSO ₄ , and the solvent was distilled off under reduced pressure. The reaction product was purified by column chromatography (CH ₃ Cl:Hex = 1:4), and recrystallized with ethanol to obtain 5.2 g of compound 2. A peak was confirmed at M/Z=541 by measuring the mass spectrum of the obtained solid. The mass spectrum data of Compound 2 is shown in FIG. 4.

Synthesis Example 3. Preparation of Compound 3

1) Preparation of Intermediate C

30.8 g of Intermediate C was obtained in the same manner as in the synthesis of Intermediate A of Synthesis Example 1, except that 25.1 g (0.11 mol) of dibenzo[b,d]thiophen-1-yl-boronic acid was used. A peak was confirmed at M/Z=445 by measuring the mass spectrum of the obtained solid.

2) Preparation of compound 3

In the same manner as in the synthesis of compound 1 of Synthesis Example 1, except that 13.4 g (0.03 mol) of the intermediate C was used, 5.0 g of compound 3 was obtained. A peak was confirmed at M/Z=557 by measurement of the mass spectrum of the obtained solid.

Synthesis Example 4. Preparation of compound 4

1) Preparation of intermediate D

In the same manner as in the synthesis of Intermediate B of Synthesis Example 2, except that 23.3 g (0.11 mol) of dibenzo[b,d]furan-1-yl-boronic acid was used, 24.8 g of compound D was obtained. A peak was confirmed at M/Z=429 by measuring the mass spectrum of the obtained solid.

2) Preparation of compound 4

In the same manner as in the synthesis of compound 2 of Synthesis Example 2, except that 12.9 g (0.03 mol) of intermediate D was used, 4.0 g of compound 4 was obtained. A peak was confirmed at M/Z=541 by measuring the mass spectrum of the obtained solid.

Synthesis Example 5. Preparation of compound 5

1) Preparation of Intermediate E

A mixed solution containing 8.0 g (0.0143 mol) of compound 1 prepared in Synthesis Example 1 and a mixed solution containing 100 ml of tetrahydrofuran (THF) was added dropwise to 7.4 mL (18.6 mmol) of 2.5 M n-BuLi at -78 °C. And stirred at -40°C for 8 hours. Trimethyl borate 4.8mL (42.9 mmol) was added dropwise at -78 °C, and the mixture was heated to 0 °C and stirred for 2 hours. After the reaction was completed, distilled water and chloroform were added and extracted at room temperature, and the organic layer was dried over MgSO ₄ and distilled under reduced pressure to remove the solvent. The reaction product was purified by column chromatography (CH ₃ Cl:Hex = 1:4) to obtain 5.4 g of Intermediate E.

2) Preparation of compound 5

Intermediate E 6.0 g (0.01 mol), phenyl-boronic acid 1.3 g (0.011 mol), Pd(PPh ₃ ) ₄ 0.58 g (0.5 mmol), K ₂ CO ₃ 4.1 g (0.03 mol) in tetrahydrofuran/distilled water 24 After dissolving in ml/8 ml, the mixture was stirred under reflux for 12 hours under nitrogen conditions. After cooling to room temperature, chloroform was added and extracted, the organic layer was dried over MgSO ₄ , and the solvent was distilled off under reduced pressure. The reaction product was purified by column chromatography (CH ₃ Cl:Hex=1:6), and recrystallized with ethanol to obtain 3.0 g of compound 5. A peak was confirmed at M/Z=633 by measuring the mass spectrum of the obtained solid.

Synthesis Example 6. Preparation of compound 6

1) Preparation of Intermediate F

In the same manner as in the synthesis of Intermediate E of Synthesis Example 5, except that 8.0 g (0.0143 mol) of Compound 2 prepared in Synthesis Example 2 was used instead of Compound 1, 4.8 g of Intermediate F was obtained.

2) Preparation of compound 6

In the same manner as in the synthesis of compound 5 of Synthesis Example 5, except that 6.0 g (0.01 mol) of intermediate F was used instead of intermediate E, 2.8 g of compound 6 was obtained. A peak was confirmed at M/Z=617 by measurement of the mass spectrum of the obtained solid.

Synthesis Example 7. Preparation of compound 7

1) Preparation of intermediate G

2-bromo-6-iododibenzo[b,d]thiophene 11.7 g (0.03 mol), 9H-carbazole-3-carbonitrile 5.8 g (0.03 mol), CuI 5.7 g (0.03 mol), 1 ,10-phenanthroline (1,10-Phenanthroline) 8.7 g (0.048 mol), K ₃ PO ₄ 9.0 g (0.036 mol) was dissolved in xylene and stirred under reflux for 24 hours. After cooling to room temperature, chloroform and distilled water were added for extraction, and the organic layer was dried over MgSO ₄ , and the solvent was distilled off under reduced pressure. The reaction product was purified by column chromatography (CH ₃ Cl:Hex=1:2), and recrystallized with ethanol to obtain 6.4 g of compound G. A peak was confirmed at M/Z=428 by measurement of the mass spectrum of the obtained solid.

2) Preparation of compound 7

Intermediate G 4.3 g (0.01 mol), dibenzo[b,d]thiophen-4-yl-boronic acid 2.1 g (0.011 mol), Pd(PPh ₃ ) ₄ 0.58 g (0.5 mmol), K ₂ CO ₃ 4.1 g (0.03 mol) was dissolved in 30 ml/10 ml of tetrahydrofuran/distilled water and stirred under reflux for 12 hours under nitrogen conditions. After cooling to room temperature, chloroform was added and extracted, the organic layer was dried over MgSO ₄ , and the solvent was distilled off under reduced pressure. The reaction product was purified by column chromatography (CH ₃ Cl:Hex = 1:6), and recrystallized with ethanol to obtain 3.2 g of compound 7. A peak was confirmed at M/Z=557 by measurement of the mass spectrum of the obtained solid.

Synthesis Example 8. Preparation of compound 8

1) Preparation of compound 8

Using 2.1 g (0.011 mol) of dibenzo[b,d]thiophen-1-yl-boronic acid, 3.0 g of compound 8 was obtained in the same manner as in the synthesis of compound 7. A peak was confirmed at M/Z=557 by measurement of the mass spectrum of the obtained solid.

Synthesis Example 9. Preparation of compound 9

1) Preparation of compound 9

4-([1,1'-biphenyl]-3-yl)-2-bromo-6-iododibenzo[b] instead of 2-bromo-6-iododibenzo[b,d]thiophene In the same manner as in the synthesis of compound 7 except that 16.2 g (0.03 mol) of thiophene was used, 3.8 g of compound 9 was obtained. A peak was confirmed at M/Z=709 by measurement of the mass spectrum of the obtained solid.

Synthesis Example 10. Preparation of Compound 10

1) Preparation of compound 10

4-([1,1'-biphenyl]-3-yl)-2-bromo-6-iododibenzo[b] instead of 2-bromo-6-iododibenzo[b,d]thiophene Using 16.2 g (0.03 mol) of thiophene, and dibenzo[b,d]furan-4-yl-boronic acid instead of dibenzo[b,d]thiophen-4-yl-boronic acid Except for the same method as in the synthesis of compound 7, to obtain 3.8 g of compound 10. A peak was confirmed at M/Z=693 by measuring the mass spectrum of the obtained solid.

Synthesis Example 11. Preparation of compound 11

1) Preparation of compound 11

3.2 g of compound 11 was obtained by the same method as the synthesis of compound 7 using 2.1 g of (6-phenyldibenzo[b,d]furan-2-yl)boronic acid. A peak was confirmed at M/Z=617 by measurement of the mass spectrum of the obtained solid.

Synthesis Example 12. Preparation of compound 12

1) Preparation of compound 12

Using 2.1 g of (6-phenyldibenzo[b,d]furan-4-yl)boronic acid, 3.6 g of compound 12 was obtained in the same manner as in the synthesis of compound 7. A peak was confirmed at M/Z=617 by measurement of the mass spectrum of the obtained solid.

Synthesis Example 13. Preparation of compound 13

1) Preparation of compound 13

Using 2.1 g of (6-cyanodibenzo[b,d]furan-4-yl)boronic acid, 3.4 g of compound 13 was obtained in the same manner as in the synthesis of compound 7. A peak was confirmed at M/Z=566 by measuring the mass spectrum of the obtained solid.

Synthesis Example 14. Preparation of compound 14

1) Preparation of compound 14

Using 2.1 g of (6-cyanodibenzo[b,d]furan-2-yl)boronic acid, 3.8 g of compound 14 was obtained in the same manner as in the synthesis of compound 7. A peak was confirmed at M/Z=566 by measuring the mass spectrum of the obtained solid.

<Example>

Example 1: Fabrication of organic light emitting device

First, a glass substrate with an ITO electrode having a thickness of 40 mm x 40 mm x 0.5 mm was subjected to ultrasonic cleaning for 5 minutes with isopropyl alcohol, acetone, and DI water, and then dried in an oven at 100°C. After cleaning the substrate, it was subjected to O ₂ plasma treatment in a vacuum state for 2 minutes, and then transferred to the deposition chamber to deposit other layers thereon.

The following compound HAT-CN was deposited to a thickness of 10 nm on ITO of a glass substrate by evaporation from a heating boat under a vacuum of about 10 ^-7 Torr to form a hole injection layer.

After depositing the following compound NPB at 75 nm on the hole injection layer to form a hole transport layer, the following compound mCBP was deposited thereon to a thickness of 15 nm to form an electron blocking layer.

Subsequently, on the electron blocking layer, the following Compound 1 and the following Compound TD1 were deposited in a weight ratio of 90:10 with a film thickness of 35 nm to form an emission layer.

A hole blocking layer was formed by depositing the following compound B3PYMPM having a thickness of 10 nm on the emission layer, and then the following compound TPBi was deposited on the hole blocking layer to form an electron transport layer having a thickness of 25 nm.

Subsequently, lithium fluoride (LiF) at a thickness of 80 nm and aluminum at a thickness of 100 nm were sequentially deposited on the electron transport layer to form an electron injection layer and a cathode, respectively.

Then, after the CPL (capping layer) was formed, it was encapsulated with glass. After the deposition of these layers, they were transferred from the deposition chamber into a drying box for film formation, and subsequently encapsulated using a UV-curing epoxy and a moisture getter, thereby manufacturing an organic light-emitting device.

In the above process, the deposition rate of the organic material was maintained at 10 nm/s.

The compound used in Example 1 is as follows.

Examples 2 to 14

An organic light-emitting device was manufactured in the same manner as in Example 1, except that Compounds 2 to 14 were used instead of Compound 1 in Example 1.

Comparative Examples 1 to 6

An organic light-emitting device was manufactured in the same manner as in Example 1, except that the following compounds A to F were used instead of compound 1 in Example 1.

Physical properties were measured for the organic light-emitting devices prepared in Examples 1 to 14 and Comparative Examples 1 to 6 each prepared by setting the thickness of the light emitting layer on which the delayed fluorescent host was deposited to 90% by weight to 35 nm. Device properties were evaluated at room temperature using a current source (KEITHLEY) and a photometer (PR 650). Driving voltage (V), current efficiency (cd/A), power efficiency (lm/W), luminance (cd/m ² ), measured at a current density of 10 ㎃/㎠ for each organic light emitting device, at 3000 nit The time until the brightness decreases to 95% (T ₉₅ ) was measured. The measurement results are shown in Table 1 below.

compound Driving voltage (V) Current efficiency
(cd/A) Power efficiency
(lm/W) Luminance (cd/m ² ) T ₉₅ Example 1 Compound 1 4.2 60.2 45.03 6020 380 Example 2 Compound 2 4 62 48.70 6200 460 Example 3 Compound 3 3.8 55.4 45.80 5540 240 Example 4 Compound 4 4.4 55.8 39.84 5580 300 Example 5 Compound 5 4 52.4 41.16 5240 260 Example 6 Compound 6 4.6 53.2 36.33 5320 240 Example 7 Compound 7 4.4 60.2 42.98 6020 260 Example 8 Compound 8 4.2 60.2 45.03 6020 420 Example 9 Compound 9 8 56.8 22.31 5680 300 Example 10 Compound 10 8 55.2 21.68 5520 280 Example 11 Compound 11 4.2 53.8 40.24 5380 300 Example 12 Compound 12 4.6 58.2 39.75 5820 480 Example 13 Compound 13 4.2 57 42.64 5700 360 Example 14 Compound 14 4.6 56.4 38.52 5640 340 Comparative Example 1 Compound A 6.8 46 21.25 4600 160 Comparative Example 2 Compound B 6.4 40 19.64 4000 160 Comparative Example 3 Compound C 6.2 41.8 21.18 4180 180 Comparative Example 4 Compound D 5.2 48 29.00 4800 180 Comparative Example 5 Compound E 5.8 45 24.37 4500 160 Comparative Example 6 Compound F 5.2 46.8 28.27 4680 190

The heterocyclic compound of the present invention is characterized in that a carbazole group substituted with a cyano group is bonded to the position 2 or 6 of the dibenzothiophene, and a dibenzofuran group or a dibenzothiophene group is bonded to the remaining position. On the other hand, compounds A to F of Comparative Examples 1 to 6 have a carbazole group substituted with a group other than a cyano group, or positions 2 and 6 of dibenzothiophene are substituted only with a carbazole group or a dibenzofuran group, or , Instead of a dibenzofuran group or a dibenzothiophene group, an aryl group and the like are included.

The organic light-emitting devices of Examples 1 to 14 using the heterocyclic compound of the present invention have low driving voltage, high current efficiency, high power efficiency, high luminance, and lifetime characteristics, compared to the devices of Comparative Examples 1 to 6. I could confirm this high

1: substrate
2: anode
3: hole injection layer
4: hole transport layer
5: electron blocking layer
6: light emitting layer
7: hole blocking layer
8: electron transport layer
9: electron injection layer
10: cathode
11: capsule

Claims (14)

Compound represented by the following formula (1):
[Formula 1]

In Formula 1,
X is hydrogen; Cyano group; A substituted or unsubstituted phenyl group; Or a substituted or unsubstituted biphenyl group,
Any one of A and B is a carbazole group substituted with a cyano group, and the other is a substituted or unsubstituted dibenzofuran group; Or a substituted or unsubstituted dibenzothiophene group. The method according to claim 1,
Any one of A and B is a carbazole group substituted with a cyano group, and the other is a dibenzofuran group unsubstituted or substituted with a cyano group, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 30 carbon atoms; Or a cyano group, a C1-C20 alkyl group, or a C6-C30 aryl group substituted or unsubstituted dibenzothiophene group. The method according to claim 1,
The compound represented by Formula 1 is a compound represented by the following Formula 2 or 3:
[Formula 2]

[Formula 3]

In Formulas 2 and 3,
The definition of X is as defined in Formula 1,
X1 is O or S,
R1 and R2 are the same as or different from each other, and each independently hydrogen; heavy hydrogen; Halogen group; Cyano group; A substituted or unsubstituted silyl group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group,
n1 and n2 are integers of 0 to 7, and when n1 and n2 are each 2 or more, the substituents in the parentheses of 2 or more are the same or different from each other. The method according to claim 1,
The compound represented by Formula 1 is a compound represented by any one of the following compounds:

. The method according to claim 1,
The compound represented by Formula 1 has a minimum triplet energy level of 2.7 eV or more. The method according to claim 1,
The compound represented by Chemical Formula 1 has a glass transition temperature of 120°C or higher. A first electrode; A second electrode provided to face the first electrode; And at least one organic material layer provided between the first electrode and the second electrode, wherein at least one of the organic material layers comprises the compound according to any one of claims 1 to 6 . The method of claim 7,
The organic material layer includes a hole injection layer or a hole transport layer, and the hole injection layer or the hole transport layer includes the compound. The method of claim 7,
The organic material layer includes an electron transport layer or an electron injection layer, and the electron transport layer or the electron injection layer includes the compound. The method of claim 7,
The organic material layer includes an emission layer, and the emission layer includes the compound. The method of claim 7,
The organic material layer includes an emission layer, and the emission layer includes the compound as a host of the emission layer. The method of claim 11,
The emission layer further includes a thermally activated delayed fluorescent dopant. The method of claim 12,
The thermally activated delayed fluorescent dopant has a triplet energy level-a singlet energy level (T1-S1, ΔE _ST ) of 0.3 eV or less. The method of claim 12,
The organic light-emitting device having a maximum emission peak of 450 nm to 550 nm of the thermally activated delayed fluorescent dopant.

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