阅读说明：本技术 一种手性有机发光材料及其应用 (Chiral organic luminescent material and application thereof ) 是由 杨楚罗 倪凡 于 2020-07-03 设计创作，主要内容包括：本发明公开一种手性有机发光材料及其应用；所述手性有机发光材料的结构通式如式Ⅰ<Image he="382" wi="331" file="DDA0002568734060000011.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>所示；本发明以手性二氢茚并吖啶为电子给体(D),通过向其引入合适的电子受体(A)构成具有D-A结构的电荷转移态手性有机发光材料；手性二氢茚并吖啶作为D具有大的空间位阻,有利于D-A间形成大的扭转以减少前线分子轨道的重叠,从而减小单重态-三重态能级差(ΔE<Sub>ST</Sub>),活化反向系间窜越过程以实现延迟荧光发射,提高器件的激子利用率；另一方面,手性二氢茚并吖啶中的刚性手性季碳可以使该手性有机发光材料具有圆偏振发光性质,这使得基于其的有机电致发光器件具有圆偏振电致发光性质,为电致发光透过四分之一波长片与偏振片提供了有效保证。(The invention discloses a chiral organic luminescent material and application thereof; the structural general formula of the chiral organic luminescent material is as shown in formula I Shown; the chiral indenocridine is taken as an electron donor (D), and a proper electron acceptor (A) is introduced into the chiral indenocridine to form the charge transfer state chiral organic luminescent material with a D-A structure; the chiral indanoacridine as D has large steric hindrance, and is favorable for forming large torsion between D and A to reduce the overlap of front line molecular orbitals, thereby reducing the singlet-triplet energy level difference (delta E) ST ) Activating the reverse intersystem crossing process to delay fluorescence emission and improve the exciton utilization rate of the device; on the other hand, the rigid chiral quaternary carbon in the chiral indanthroacridine can enable the chiral organic luminescent material to have circular polarization luminescence property, so that an organic electroluminescent device based on the chiral organic luminescent material has circular polarization electroluminescence property, and effective guarantee is provided for electroluminescence to penetrate through the quarter-wavelength plate and the polaroid.)

1. The chiral organic luminescent material is characterized in that the structural general formula of the chiral organic luminescent material is as shown in formula I

in the formula I, A₁Selected from alkenyl, alkynyl, amino, nitro, carbonyl, sulfone, halogen, cyano, alkyl, alkoxy, substituted C₆～C₆₀Aromatic ring group of (2), unsubstituted C₇～C₆₀Aromatic ring group of (1), substituted or unsubstituted C₃～C₆₀An aromatic heterocyclic group of (a);

A₂selected from alkenyl, alkynyl, amino, nitro, carbonyl, sulfone, halogen, cyano, C₂～C₂₀Alkyl, alkoxy, substituted C₆～C₆₀Aromatic ring group of (2), unsubstituted C₇～C₆₀Aromatic ring group of (1), substituted or unsubstituted C₃～C₆₀An aromatic heterocyclic group of (a);

R₁-R₃independently selected from hydrogen, deuterium, alkenyl, alkynyl, amino, nitro, carbonyl, sulfone, halogen, cyano, alkyl, alkoxy, substituted C₆～C₆₀Aromatic ring group of (2), unsubstituted C₇～C₆₀Aromatic ring group of (1), substituted or unsubstituted C₃～C₆₀An aromatic heterocyclic group of (a);

A₁、A₂、R₁、R₂and R ₃Are not connected or bonded by covalent bonds.

2. The chiral organic light-emitting material of claim 1, wherein A is₁Selected from methyl, ethyl, phenyl, benzyl,

3. The chiral organic light-emitting material of claim 1, wherein A is₂Is selected from

4. The chiral organic light emitting material of claim 1, wherein the chiral organic light emitting material is

5. An electronic device comprising the chiral organic light emitting material according to any one of claims 1 to 4.

6. The electronic device according to claim 5, wherein the electronic device is an organic electroluminescent device, an organic solar cell, an organic field effect transistor, an organic light emitting field effect transistor, an organic laser, an organic sensor, or an organic spintronic device.

7. The electronic device according to claim 6, wherein the electronic device is an organic electroluminescent device comprising a functional layer, and the functional layer is composed of 0.1 to 100% by mass of the chiral organic light-emitting material and 0 to 99.9% by mass of an organic functional material.

8. The electronic device according to claim 7, wherein the organic functional material is selected from one of a hole injection material, a hole transport material, a hole blocking material, an electron injection material, an electron transport material, an electron blocking material, an exciton blocking material, a fluorescent material, a phosphorescent material, a host material, and an organic dye.

9. The electronic device of claim 6, wherein the electronic device is an organic electroluminescent device comprising a light-emitting layer comprising the chiral organic light-emitting material.

10. Use of an electronic device according to any of claims 5 to 9 in an electronic device.

Technical Field

The invention relates to the technical field of electroluminescent materials, in particular to a chiral organic luminescent material and preparation and application thereof.

Background

Organic light-emitting diodes (OLEDs for short) have the advantages of self-luminescence, fast response, wide visibility, low driving voltage, energy saving, lightness and thinness, flexible processing and the like, and greatly meet the requirement of consumers on continuous update of display technology. Meanwhile, the OLED has wide application prospect and huge market demand in the field of illumination.

OLEDs are typically composed of a conductive anode, a hole transport layer, a light emitting layer, an electron transport layer, and a conductive cathode. Among them, the organic light emitting material of the light emitting layer directly determines the performance of the OLED device, so that the development of a novel, stable and efficient organic light emitting material is the focus of research in this field. The OLED light emitting material has undergone the development process of the conventional fluorescent material, phosphorescent material and Thermally Activated Delayed Fluorescence (TADF) material. According to spin statistics, the ratio of singlet excited state to triplet excited state generated after holes and electrons are combined in the organic electroluminescent device is 1: 3. the traditional fluorescent material only utilizes singlet excited state to emit light, so the upper limit of the exciton utilization rate in the electroluminescent process is 25%, which directly leads the OLED based on the material to be difficult to break through the limit of 5% of external quantum efficiency. In 1997, the appearance of phosphorescent materials capable of realizing 100% exciton utilization rate greatly improves the device efficiency of the OLED; however, since the phosphorescent material must use a noble metal element such as iridium (Ir) or platinum (Pt), the material cost is increased. In 2009, research shows that the application of TADF materials to OLEDs can also make the theoretical exciton utilization rate reach 100%, and due to the purely organic characteristics of TADF materials, TADF materials are cheap, and thus have great commercial application potential.

To date, OLEDs based on TADF materials of different color light have achieved higher efficiency in the full visible range, yet their direct utilization remains challenging. The main reason is that in the practical use of the OLED, a polarizer and a quarter-wave plate need to be introduced to improve the light emitting contrast, which results in half of the light emitting efficiency of the device. The circularly polarized light can effectively transmit the polaroid and the quarter-wave plate, thereby avoiding the loss of light extraction efficiency, and the development of a Circular Polarized Thermally Activated Delayed Fluorescence (CPTADF) material can simultaneously realize the high internal conversion and external extraction efficiency of the OLED. Therefore, the development of the CPTADF material and the research on the performance of the corresponding Circular Polarized Organic Light Emitting Diode (CPOLED) thereof have great significance for the further development of the OLED display technology. However, the CPTADF material capable of being used for CPOLED preparation has only been reported, and the reported material cannot achieve the combination of high photoluminescence quantum yield, high thermal activation delayed fluorescence ratio and high circularly polarized luminescence asymmetry factor, so that the CPOLED with high performance is still difficult to achieve.

Accordingly, the prior art is yet to be improved and developed.

Disclosure of Invention

In view of the above-mentioned shortcomings of the prior art, the present invention aims to provide a chiral organic light emitting material, and a preparation method and an application thereof, and aims to solve the problems that the existing organic light emitting material is difficult to be compatible with high photoluminescence quantum yield, high thermal activation delayed fluorescence ratio and high circularly polarized light emission asymmetry factor.

The technical scheme of the invention is as follows:

a chiral organic luminescent material has a structural general formula as shown in formula I

Shown;

in the formula I, A₁Selected from alkenyl, alkynyl, amino, nitro, carbonyl, sulfone, halogen, cyano, alkyl, alkoxy, substituted C₆～C₆₀Aromatic ring group of (2), unsubstituted C₇～C₆₀Aromatic ring group of (1), substituted or unsubstituted C₃～C₆₀An aromatic heterocyclic group of (a);

A₂selected from alkenyl, alkynyl, amino, nitro, carbonyl, sulfone, halogen, cyano, C₂～C₂₀Alkyl, alkoxy, substituted C₆～C₆₀Aromatic ring group of (2), unsubstituted C₇～C₆₀Aromatic ring group of (1), substituted or unsubstituted C₃～C₆₀An aromatic heterocyclic group of (a);

R₁-R₃independently selected from hydrogen, deuterium, alkenyl, alkynyl, amino, nitro, carbonyl, sulfone, halogen, cyano, alkyl, alkoxy, substituted C₆～C₆₀Aromatic ring group of (2), unsubstituted C₇～C₆₀Aromatic ring group of (1), substituted or unsubstituted C ₃～C₆₀An aromatic heterocyclic group of (a);

A₁、A₂、R₁、R₂and R₃Are not connected or bonded by covalent bonds.

An electronic device, wherein the electronic device comprises a chiral organic light emitting material as described above.

Use of an electronic device as described above in an electronic device.

Has the advantages that: the chiral indenocridine is taken as an electron donor (D), and a proper electron acceptor (A) is introduced into the chiral indenocridine to form the charge transfer state chiral organic luminescent material with a D-A structure; on one hand, the chiral indanoacridine as an electron donor has large steric hindrance, and is beneficial to forming large torsion between D-A so as to reduce the overlap of front-line molecular orbitals, thereby reducing the singlet-triplet energy level difference (delta E)_ST) Activating the reverse intersystem crossing process to delay fluorescence emission and improve the exciton utilization rate of the device; on the other hand, the rigid chiral quaternary carbon in the chiral indanthroacridine enables the chiral organic luminescent material to have circular polarization luminescence property, so that an organic electroluminescent device based on the chiral organic luminescent material has circular polarization electroluminescence property, and effective guarantee is provided for electroluminescence to penetrate through the quarter-wavelength plate and the polaroid.

Drawings

FIG. 1 shows 1.0X 10 in example 6 of the present invention ^-4Circular dichroism of (S) -P3 and (R) -P3 in toluene solution of M;

FIG. 2 shows 1.0X 10 in example 6 of the present invention^-4Circularly polarized photoluminescence spectra of (S) -P3 and (R) -P3 in a toluene solution of M;

FIG. 3 shows 1.0X 10 in example 6 of the present invention^-4The photo-induced circular polarization luminescence asymmetry factors of (S) -P3 and (R) -P3 in the toluene solution of M.

FIG. 4 shows a graph of 1.0X 10 in example 6 of the present invention^-4Circular dichroism of (S) -P23 and (R) -P23 in toluene solution of M;

FIG. 5 shows a graph of 1.0X 10 in example 6 of the present invention^-4Circularly polarized photoluminescence spectra of (S) -P23 and R) -P23 in a toluene solution of M;

FIG. 6 shows 1.0X 10 in example 6 of the present invention^-4The photo-induced circular polarization luminescence asymmetry factors of (S) -P23 and (R) -P23 in the toluene solution of M.

Detailed Description

The invention provides a chiral organic luminescent material and an application thereof, and the invention is further described in detail below in order to make the purpose, technical scheme and effect of the invention clearer and clearer. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The embodiment of the invention provides a chiral organic luminescent material, which has a structural general formula as shown in formula I

Shown;

In the formula I, A₁Can be selected from alkenyl, alkynyl, amino, nitro, carbonyl, sulfone, halogen, cyano, alkyl, alkoxy, substituted C₆～C₆₀Aromatic ring group of (2), unsubstituted C₇～C₆₀Aromatic ring group of (1), substituted or unsubstituted C₃～C₆₀An aromatic heterocyclic group of (a);

A₂can be selected from alkenyl, alkynyl, amino, nitro, carbonyl, sulfone, halogen, cyano, C₂～C₂₀Alkyl, alkoxy, substituted C₆～C₆₀Aromatic ring group of (2), unsubstituted C₇～C₆₀Aromatic ring group of (1), substituted or unsubstituted C₃～C₆₀An aromatic heterocyclic group of (a);

R₁-R₃can be independently selected from hydrogen, deuterium, alkenyl, alkynyl, amino, nitro, carbonyl, sulfonyl, halogen, cyano, alkyl, alkoxy and substituted C₆～C₆₀Aromatic ring group of (2), unsubstituted C₇～C₆₀Aromatic ring group of (1), substituted or unsubstituted C₃～C₆₀An aromatic heterocyclic group of (a);

A₁、A₂、R₁、R₂and R₃Are not connected or bonded by covalent bonds.

In the embodiment, chiral indenocridine is taken as an electron donor (D), and a charge transfer state chiral organic luminescent material with a D-A structure is formed by introducing a proper electron acceptor (A) into the chiral indenocridine; on one hand, the chiral indanoindine as the electron donor has large steric hindrance and is beneficial to forming large space between D-ATwisting to reduce overlap of the molecular orbitals of the front lines and thereby reduce the singlet-triplet energy level difference (Δ E) _ST) Activating the reverse intersystem crossing process to delay fluorescence emission and improve the exciton utilization rate of the device; on the other hand, the rigid chiral quaternary carbon in the chiral indanthroacridine enables the chiral organic luminescent material to have circular polarization luminescence property, so that an organic electroluminescent device based on the chiral organic luminescent material has circular polarization electroluminescence property, and effective guarantee is provided for electroluminescence to penetrate through the quarter-wavelength plate and the polaroid.

Specifically, in the present embodiment, R₁Is R₁At an arbitrary substitution position of the benzene ring, R₂Is R₂At an arbitrary substitution position of the benzene ring, R₃Is R₃Any substituted position of the benzene ring; the chiral organic luminescent material comprises a chiral absolute configuration of S-type isomer and/or R-type isomer; wherein the structural formula of the S-type isomer is shown as the formula S-I

The structural formula of the R-type isomer is shown as the formula R-IIn the formulae S-I, R-I, A₁Selected from alkenyl, alkynyl, amino, nitro, carbonyl, sulfone, halogen, cyano, alkyl, alkoxy, substituted C₆～C₆₀Aromatic ring group of (2), unsubstituted C₇～C₆₀Aromatic ring group of (1), substituted or unsubstituted C₃～C₆₀An aromatic heterocyclic group of (a); a. the₂Selected from alkenyl, alkynyl, amino, nitro, carbonyl, sulfone, halogen, cyano, C ₂～C₂₀Alkyl, alkoxy, substituted C₆～C₆₀Aromatic ring group of (2), unsubstituted C₇～C₆₀Aromatic ring group of (1), substituted or unsubstituted C₃～C₆₀An aromatic heterocyclic group of (a); r₁-R₃Independently selected from hydrogen, deuterium, alkenyl, alkynyl, amino, nitro, carbonyl, sulfone, halogen, cyano, alkyl, alkoxy, substituted C₆～C₆₀Aromatic ring group of (2), unsubstituted C₇～C₆₀Aromatic ring group of (1), substituted or unsubstituted C₃～C₆₀An aromatic heterocyclic group of (a); a. the₁、A₂、R₁、R₂And R₃Are not connected or bonded by covalent bonds. The chiral organic luminescent material is prepared by adopting the existing or substituted chiral indanoindoline through Buchwald-Hartwig coupling, Ullmann coupling or aromatic nucleophilic extraction; or the existing or substituted chiral indanthroacridine racemate is adopted to obtain the chiral organic luminescent material racemate through Buchwald-Hartwig coupling, Ullmann coupling or aromatic nucleophilic extraction, and then chiral separation is carried out on the chiral organic luminescent material racemate by adopting chiral high performance liquid chromatography, thereby obtaining the chiral organic luminescent materials with the absolute configuration of R configuration and S configuration respectively.

The chiral organic light-emitting material of the embodiment has the following advantages: (1) having a highly distorted D-A structure, Δ E thereof_STNot more than 0.3eV, high efficiency reverse intersystem crossing and delayed fluorescence emission can be realized at room temperature. (2) The emission of multiple color lights can be realized by introducing electron acceptors with different intensities; meanwhile, the chiral transition metal oxide is used as a luminescent layer host or guest material to be applied to an organic electroluminescent device, has good comprehensive performance, and can provide chiral transfer from a chiral host material to a chiral guest material or an achiral guest material. (3) The material has an obvious rigid molecular structure, can effectively limit the non-radiative transition of an excited singlet state, and further obtains an ideal photoluminescence quantum yield; meanwhile, the rigid molecular structure provides guarantee for the stability of chirality and the stability of circular polarization luminescence. (4) The introduction of the chiral quaternary carbon of the chiral indanthroacridine is beneficial to the reduction of the conjugation degree caused by the structural torsion of the electron donor, so that the electron donor has high triplet state energy level, and the chiral indanthroacridine can be used for the design of all visible light and near-infrared circularly-polarized thermally-activated delayed fluorescent materials.

In one embodiment, A₁Can be selected from, but not limited to, methyl, ethyl, phenyl, benzyl, Wherein the position of the curved bond on the benzene ring is A₁The connection bit of (1). Preferably, A₁Can be selected from methyl, phenyl,

In one embodiment, A₂Can be selected from but not limited to

Wherein, the random substitution position of the curved bond on the benzene ring is A₂The connection bit of (1). Preferably, A₂Is selected from

Wherein the position of the curved bond on the benzene ring is A₂The connection bit of (1). Within the above range, A₂The organic luminescent material with the D-A structure formed by the chiral indanthroacridine is connected with the A in a large torsion mode, so that an intramolecular charge transfer state is formed, the overlapping of front line molecular orbitals is inhibited, and the formed D-A type organic luminescent material has smaller singlet state energy level difference and better thermal activation delayed fluorescence property.

In one embodimentThe chiral organic light emitting material may be, but is not limited to

That is, R₁-R₃Are all H; of course, the compounds P1-P96 shown in the above structures may correspondingly include isomers of which the chiral absolute configuration is S type and/or R type. Preferably, the chiral organic light-emitting material is

The chiral organic light emitting material in the above range has typical intramolecular charge transfer properties, sufficiently small singlet energy level difference and significant thermally activated delayed fluorescence properties.

Embodiments of the present invention further provide an electronic device, wherein the electronic device includes the chiral organic light emitting material as described in any of the above.

In one embodiment, the electronic device is an organic electroluminescent device, an organic solar cell, an organic field effect transistor, an organic light emitting field effect transistor, an organic laser, an organic sensor, or an organic spintronic device.

In one embodiment, the electronic device is an organic electroluminescent device, and the organic electroluminescent device comprises a functional layer, wherein the functional layer is composed of 0.1-100% by mass of the chiral organic luminescent material and 0-99.9% by mass of an organic functional material.

In one embodiment, the organic functional material is selected from one of a hole injection material, a hole transport material, a hole blocking material, an electron injection material, an electron transport material, an electron blocking material, an exciton blocking material, a fluorescent material, a phosphorescent material, a host material, and an organic dye.

In one embodiment, the electronic device is an organic electroluminescent device comprising a light-emitting layer comprising the chiral organic light-emitting material.

Further in one embodiment, the organic electroluminescent device includes: the organic light emitting diode comprises an anode, a cathode and a light emitting layer arranged between the anode and the cathode, wherein the light emitting layer comprises the chiral organic light emitting material. In one embodiment, the chiral organic light emitting material is 0.1 to 100% by weight; that is, the chiral organic light-emitting material can be used as a guest material or a host material in the light-emitting layer to prepare a doped organic electroluminescent device, and can also be used as a light-emitting layer alone to prepare a non-doped organic electroluminescent device. Preferably, the chiral organic light-emitting material is 0.1-40 wt%, that is, the chiral organic light-emitting material is used as a guest material in the light-emitting layer; preferably, the chiral organic light-emitting material has a mass content of 1-20 wt%.

In this embodiment, specifically, the organic electroluminescent device may be an inverted structure or an upright structure; of course, if necessary, a hole injection layer and/or a hole transport layer may be further disposed between the anode and the light emitting layer, and when both the hole injection layer and the hole transport layer are disposed, the hole injection layer is disposed near the anode side, and the hole transport layer is disposed near the light emitting layer side; when the electron injection layer and the electron transport layer are arranged at the same time, the electron injection layer is arranged close to one side of the cathode, and the electron transport layer is arranged close to one side of the luminous layer. The anode, the cathode, the hole injection layer, the hole transport layer, the electron injection layer and the electron transport layer of the organic electroluminescent device can be made of materials and have thicknesses as well as the thickness of the luminescent layer according to the existing organic electroluminescent device.

The embodiment of the invention also provides an application of the electronic device as described above in electronic equipment. For example, the electronic device is a display panel, which includes: the electronic device comprises a substrate base plate and a plurality of electronic devices which are arranged on the substrate base plate and are any of the above electronic devices, wherein the electronic devices are organic electroluminescent devices.

In this embodiment, specifically, the substrate base plate may be rigid or flexible.

The invention is further illustrated by the following specific examples.