阅读说明：本技术 一种基于并螺芴的芳香胺衍生物及其应用 (Aromatic amine derivative based on spirofluorene and application thereof ) 是由 张佐伦 李成龙 王悦 于 2020-03-31 设计创作，主要内容包括：一种基于并螺芴的芳香胺衍生物及其在有机电致发光器件中的应用,属于有机光电材料及其器件技术领域。该芳香胺衍生物的结构如通式(I)或通式(II)所示,其中R<Sup>1</Sup>和R<Sup>2</Sup>独立地为氢、含有1～12个碳的直链或支链烷基、苯环、含有1～12个碳的直链或支链烷基取代的苯环。本发明采用所述芳香胺衍生物作为空穴传输材料制备的有机电致发光器件具有亮度高、效率高及稳定性好的优点,能够有效提升OLED器件的性能。<Image he="315" wi="700" file="DDA0002432777950000011.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>(An aromatic amine derivative based on spirofluorene and application thereof in an organic electroluminescent device belong to the technical field of organic photoelectric materials and devices thereof. The structure of the aromatic amine derivative is shown as a general formula (I) or a general formula (II), wherein R 1 And R 2 The organic electroluminescent device prepared by using the aromatic amine derivative as a hole transport material has the advantages of high brightness, high efficiency and good stability, and can effectively improve the performance of an O L ED device.)

1. An aromatic amine derivative based on a spirofluorene has a molecular structure shown as a formula (I) or a formula (II):

wherein R is¹And R²Independently hydrogen, straight chain or branched chain alkyl containing 1-12 carbon atoms, benzene ring, and benzene ring substituted by straight chain or branched chain alkyl containing 1-12 carbon atoms.

2. The aromatic amine derivative based on a spirofluorene according to claim 1, wherein: the structural formula of the compound is any one of compounds shown in a general formula (I-1), (I-2), (I-3) or (II-1),

wherein R is¹And R²Independently hydrogen, C1-12 straight chain or branched chain alkyl, benzene ring, C1-12 straight chain or branched chain alkyl substituted benzeneAnd (4) a ring.

3. The aromatic amine derivative based on a spirofluorene according to claim 2, wherein: the structural formula of the compound is shown as one of the following formulas,

4. an organic electroluminescent device comprising a cathode, an anode and one or more organic compound layers interposed between the two electrodes, the organic compound layers comprising at least a hole transport layer, a light emitting layer and an electron transport layer; the method is characterized in that: the aromatic amine derivative based on a spirofluorene according to any one of claims 1 to 3, alone or together with other materials, as a hole transport layer.

5. An organic electroluminescent device comprises a cathode, an anode and one or more organic compound layers disposed between the cathode and the anode, wherein the organic compound layers at least comprise a first hole transport layer I, a second hole transport layer II, a light-emitting layer and an electron transport layer; the method is characterized in that: the aromatic amine derivative based on a spirofluorene according to any one of claims 1 to 3, alone or together with other materials, as a hole transport layer II.

6. The organic electroluminescent device as claimed in any one of claims 4 to 5 for use in the production of an organic electroluminescent display, an organic electroluminescent lighting source or a decorative lighting source.

Technical Field

The invention belongs to the technical field of organic photoelectric materials and devices thereof, and particularly relates to an aromatic amine derivative based on spirofluorene and application thereof in an organic electroluminescent device.

Background

An Organic electroluminescent Device (O L ED: Organic L light Emitting Device) is a light Emitting diode in which a light Emitting layer is a film made of an Organic compound, the light Emitting layer of the Organic compound is sandwiched between two electrodes (anode and cathode), and the O L ED Device can emit light at a certain driving voltage, and O L ED is applied to a flat panel display because of its high illumination, low weight, ultra-thin profile, self-illumination without backlight, low power consumption, and fast response speed.

An O L ED device is typically composed of layers of organic material between an anode and a cathode, including a hole transport layer (HT L), a light emitting layer (EM L), an electron transport layer (ET L). the basic mechanism of an O L ED device involves injecting carriers, transporting, recombining carriers, and forming excitons to emit light when an external voltage is applied to an O L ED device, electrons and holes are injected from the cathode and anode, respectively, electrons will be injected from the cathode into the electron transport layer, holes will be injected from the anode into the hole transport layer, and when electrons and holes are further injected into the light emitting layer they will recombine with each other to form excitons, which will emit photons when they change from an excited state to a ground state.

O L ED devices generally require the preparation of a hole blocking layer (HB L) between the light emitting layer (EM L) and the electron transporting layer (ET L), or the preparation of an electron blocking layer (EB L) between the light emitting layer (EM L) and the hole transporting layer (HT L), the use of HB L or EB L is intended to confine carriers in the light emitting layer, effectively improve the injection balance of electrons and holes, limit recombination of injected holes and electrons, and relax excitons generated within EM L, and thus can improve the efficiency of the device.

At present, many improvements have been made to put an organic electroluminescent device into practical use. The probability of recombination of holes and electrons can be improved by blocking electrons injected through the cathode by improving hole injection properties while improving electron blocking properties. Therefore, a hole transporting material and an electron blocking material play an important role, and it is desired to provide a material having a high hole injecting property, a large hole mobility, a high electron blocking property, and a high heat resistance.

Hole transport materials used in existing O L ED devices, such as N, N '-bis (α -naphthyl) -N, N' -diphenyl-4, 4 '-diamine (NPB) and 4, 4', 4 ″ -tris (3-methylphenylamino) triphenylamine (MTDATA), NPB are known to have good hole transport ability, but are difficult to be applied to organic light emitting devices requiring high current because of having a glass transition temperature (Tg) of 100 ℃ or less and causing a reduction in device characteristics due to crystallization under high temperature conditions, MTDATA has a glass transition temperature of 76 ℃.

Therefore, it is an urgent need to obtain a hole transport material or an electron blocking material that can reduce the driving voltage and further improve the light emitting efficiency in commercial applications.

Disclosure of Invention

The aromatic amine derivative based on the spirofluorene can be used as a hole transport material or an electron blocking material of an O L ED device.

The invention firstly provides an amine derivative based on a spirofluorene, wherein the molecular structure of the derivative is shown as a general formula (I) or a general formula (II):

wherein R is¹And R²Independently hydrogen, straight chain or branched chain alkyl containing 1-12 carbon atoms, benzene ring, and benzene ring substituted by straight chain or branched chain alkyl containing 1-12 carbon atoms.

Furthermore, the structural formula of the amine derivative based on the spirofluorene is any one of compounds shown in general formulas (I-1), (I-2), (I-3) or (II-1):

wherein R is¹And R²Independently hydrogen, straight chain or branched chain alkyl containing 1-12 carbon atoms, benzene ring, and benzene ring substituted by straight chain or branched chain alkyl containing 1-12 carbon atoms.

Preferably, the structural formula of the amine derivative based on the spirofluorene is shown as one of the following formulas:

in the present invention, the position of "substitution" may be arbitrary unless otherwise specified.

The term "alkyl" is intended to include both branched and straight chain saturated aliphatic hydrocarbon groups having the indicated number of carbon atoms.

The above preferred conditions can be arbitrarily combined to obtain preferred embodiments of the present invention without departing from the common general knowledge in the art.

The present invention employs conventional methods of mass spectrometry, elemental analysis, and the various steps and conditions can be referred to those conventional in the art unless otherwise indicated.

Unless otherwise indicated, the present invention employs standard nomenclature for analytical chemistry, organic synthetic chemistry, and optics, and standard laboratory procedures and techniques. In some cases, standard techniques are used for chemical synthesis, chemical analysis, light emitting device performance detection.

The reagents used in the present invention are commercially available.

The raw materials used by the derivative are commercially available or can be prepared according to a chemical synthesis method conventional in the field, and the steps and conditions can refer to the steps and conditions of similar reactions in the field.

The invention provides a preparation method of derivatives shown in a general formula (I) and a general formula (II), which can comprise any scheme as follows:

the first scheme is as follows:

scheme II:

wherein R is¹And R²Is as defined above.

In one synthetic embodiment of the present invention, the synthesis of some of the derivatives described by formula (I) and formula (II) utilizes the following starting materials:

the present invention also provides an organic electroluminescent device (O L ED) comprising a cathode, an anode and one or more organic compound layers interposed therebetween, wherein the organic compound layers comprise at least a hole transport layer, a light emitting layer and an electron transport layer, and the aromatic amine derivative based on a spirofluorene according to the present invention can be used as the hole transport layer alone or together with other materials.

In the O L ED device, the transparent anode can be formed by using an electrode material known per se, that is, by vapor-depositing an electrode material having a large work function such as ITO or gold on a substrate (a transparent substrate such as a glass substrate).

The material of the light-emitting layer in the present invention may be any material of light-emitting layers known in the art for organic electroluminescent devices, and may be a fluorescent or phosphorescent material.

The aromatic amine derivative based on the spirofluorene can be used as a hole transport material to be applied to two organic electroluminescent devices.

The organic electroluminescent device is used for preparing organic electroluminescent displays, organic electroluminescent lighting sources and decorative light sources.

The invention has the beneficial effects that:

the aromatic amine derivative based on the spirofluorene contains spiro [ fluorene-9, 9' -xanthene ] group and spirofluorene group. The rigid plane of the spirofluorene in the structure ensures that the derivative has higher thermal stability and chemical stability, and the compound has the advantages of containing two asymmetric pi systems and having higher triplet state energy level, which are shown by a compound with a spiro [ fluorene-9, 9' -xanthene ] structure.

The aromatic amine derivative based on the polyspirofluorene can realize the selective adjustment of a triplet state energy level and HOMO/L UMO, and also has good hole transport capacity and film forming property, so that the luminous efficiency and heat resistance of an O L ED device can be improved, the driving voltage can be reduced, and the aromatic amine derivative is an O L ED material with excellent performance.

Drawings

Fig. 1 is a schematic view of the structure of an organic electroluminescent device in comparative example 1 of the present invention.

Wherein, 1 is a transparent substrate, 2 is ITO, 3 is a hole transport layer, 4 is a luminescent layer, 5 is an electron transport layer, 6 is an electron injection layer, and 7 is a metal cathode.

Fig. 2 is a schematic view of the structure of an organic electroluminescent device in embodiments 1 to 37 according to the effect of the present invention.

Wherein, 1 is a transparent substrate, 2 is ITO, 31 is a hole transport layer I, 32 is a hole transport layer II, 4 is a luminescent layer, 5 is an electron transport layer, 6 is an electron injection layer, and 7 is a metal cathode.

Detailed Description

For further understanding of the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. But do not limit the invention to the scope of the described embodiments.

The starting materials used in the following examples are not particularly limited in their origin, and may be commercially available products or prepared by methods known to those skilled in the art.

In the following examples, the room temperature is 10-30 ℃.

Synthesis examples of the Compounds