Patent Application
20220281870
This application claims priority to Chinese Patent Application No. 202110227782.2 filed on Mar. 1, 2021, the disclosure of which is incorporated herein by reference in its entirety.
The present disclosure relates to the technical field of organic electroluminescence and in particular, to a compound, a material for an organic electroluminescent device and an application thereof.
After decades of development, organic electroluminescence (such as organic light-emitting diode, OLED) has gained considerable progress. The OLED has an internal quantum efficiency of approximately 100% and an external quantum efficiency of only about 20%. Most light is confined inside a light-emitting device due to factors such as loss of a substrate mode, surface plasmon loss and waveguide effect, resulting in the loss of a large amount of energy.
In a top emitting device, an organic capping layer (CPL) is deposited through evaporation on a translucent metal electrode Al so that an optical interference distance is adjusted, the reflection of external light is suppressed, and the extinction caused by the movement of surface plasmon is suppressed, thereby improving light extraction efficiency and light-emitting efficiency.
High requirements are imposed on the performance of a material for CPL: no absorption within the wavelength range (400 nm to 700 nm) of visible light, a high refractive index (generally, n>2.1), a low extinction coefficient (k≤0.00) within the wavelength range of 400 nm to 600 nm, a high glass transition temperature, a high molecular thermal stability, and an ability to be deposited through evaporation without thermal decomposition.
Materials for CPL in the related art still have many problems, for example, (1) the refractive index is generally below 1.9 and cannot meet the requirement for high refractive index; (2) in the case where the refractive index meets the requirement, the materials have relatively strong absorption or a relatively large extinction coefficient in the region of visible light; (3) amine derivatives with a particular structure and a high refractive index and the use of materials that have particular parameters have improved the light extraction efficiency, while the problems of light-emitting efficiency and chromaticity are still to be solved especially for blue light-emitting elements; (4) to increase the density of molecules and achieve high thermal stability, a molecular structure is designed to be large and loose so that molecules cannot be tightly packed, resulting in too many molecular gel holes during evaporation and incomplete coverage; (5) a simple design of an electron-type capping layer material to achieve the effects of electron transmission and light extraction saves a preparation cost of the device to a certain extent so that multiple effects are achieved, while the design is not conducive to light extraction and improves the light-emitting efficiency only slightly and the problem of chromaticity is not solved.
Therefore, more kinds of CPL materials with higher performance are to be developed in the art.
In view of defects in the related art, a first aspect of the present disclosure is to provide a compound, and in particular an organic electroluminescent material. The compound has a relatively high refractive index and can effectively improve the external quantum efficiency (EQE) of an organic electroluminescent device when used as a material for a capping layer. Meanwhile, the compound has a relatively small extinction coefficient in the region of blue light (400-450 nm) and hardly absorbs blue light, thereby improving the light-emitting efficiency.
To achieve the above advantages, the present disclosure adopts a solution described below.
The present disclosure provides a compound, which has a structure represented by Formula (1):
In Formula (1), R is selected from any one of substituted or unsubstituted C10-C60 fused-ring aryl and substituted or unsubstituted C6-C60 fused-ring heteroaryl.
In Formula (1), P1, P2, P3, P4, P5 and P6 are each independently selected from any one of a hydrogen atom, a deuterium atom, CD3, CD2CH3 and CD2CD3.
In Formula (1), Ar1 and Ar2 are each independently selected from any one of a single bond, substituted or unsubstituted C6-C60 arylene, substituted or unsubstituted C3-C60 heteroarylene, substituted or unsubstituted C10-C60 fused-ring arylene and substituted or unsubstituted C6-C60 fused-ring heteroarylene.
In Formula (1), X and Y are each independently selected from substituted or unsubstituted C6-C60 aryl and substituted or unsubstituted C3-C60 heteroaryl, and at least one of X and Y is selected from substituted or unsubstituted C3-C60 electron withdrawing heteroaryl.
Substituted groups in R, Ar1, Ar2, X and Y are each independently selected from any one or a combination of at least two of protium, deuterium, tritium, halogen, C1-C10 alkyl, C1-C10 haloalkyl, C1-C10 alkoxy, C6-C60 aryl and C3-C60 heteroaryl.
A second aspect of the present disclosure provides a material for an organic electroluminescent device. The material for an organic electroluminescent device includes any one or a combination of at least two of the compound as described herein.
A third aspect of the present disclosure provides an organic electroluminescent device. The organic electroluminescent device includes a first electrode layer, an organic function layer and a second electrode layer which are stacked in sequence.
The organic function layer includes the material as described herein.
A fourth aspect of the present disclosure provides another organic electroluminescent device. The organic electroluminescent device includes a first capping layer, a first electrode layer, an organic function layer and a second electrode layer which are stacked in sequence.
The first capping layer includes the material as described herein.
A fifth aspect of the present disclosure provides a display panel. The display panel includes the organic electroluminescent device as described herein.
A sixth aspect of the present disclosure is to provide a display device. The display device includes the display panel as described herein.
Compared with the related art, the present disclosure has beneficial effects described below.
The compound provided by the present disclosure has a relatively high refractive index and can effectively improve the light extraction efficiency and the external quantum efficiency (EQE) of an organic electroluminescent device when used in the organic electroluminescent device especially as a material for a capping layer. Meanwhile, the compound has a relatively small extinction coefficient in the region of blue light (400-450 nm) and hardly absorbs blue light, thereby improving the light-emitting efficiency.
In accordance with a first aspect of the present disclosure, a compound is provided. The compound has a structure represented by Formula (1):
In Formula (1), R is selected from any one of substituted or unsubstituted C10-C60 (for example, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C34, C36, C38, C40, C42, C44, C46, C48, C50, C52, C54, C56, C58 or the like) fused-ring aryl and substituted or unsubstituted C6-C60 (for example, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C34, C36, C38, C40, C42, C44, C46, C48, C50, C52, C54, C56, C58 or the like) fused-ring heteroaryl.
In Formula (1), P1, P2, P3, P4, P5 and P6 are each independently selected from any one of a hydrogen atom, a deuterium atom, CD3, CD2CH3 and CD2CD3.
In Formula (1), Ar1 and Ar2 are each independently selected from any one of a single bond, substituted or unsubstituted C6-C60 (for example, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C34, C36, C38, C40, C42, C44, C46, C48, C50, C52, C54, C56, C58 or the like) arylene, substituted or unsubstituted C3-C60 (for example, C4, C5, C6, C7, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C34, C36, C38, C40, C42, C44, C46, C48, C50, C52, C54, C56, C58 or the like) heteroarylene, substituted or unsubstituted C10-C60 (for example, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C34, C36, C38, C40, C42, C44, C46, C48, C50, C52, C54, C56, C58 or the like) fused-ring arylene and substituted or unsubstituted C6-C60 (for example, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C34, C36, C38, C40, C42, C44, C46, C48, C50, C52, C54, C56, C58 or the like) fused-ring heteroarylene.
In Formula (1), X and Y are each independently selected from substituted or unsubstituted C6-C60 (for example, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C34, C36, C38, C40, C42, C44, C46, C48, C50, C52, C54, C56, C58 or the like) aryl and substituted or unsubstituted C3-C60 (for example, C4, C5, C6, C7, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C34, C36, C38, C40, C42, C44, C46, C48, C50, C52, C54, C56, C58 or the like) heteroaryl, and at least one of X and Y is selected from substituted or unsubstituted C3-C60 (for example, C4, C5, C6, C7, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C34, C36, C38, C40, C42, C44, C46, C48, C50, C52, C54, C56, C58 or the like) electron withdrawing heteroaryl.
Substituted groups in R, Ar1, Ar2, X and Y are each independently selected from any one or a combination of at least two of protium, deuterium, tritium, halogen, C1-C10 (for example, C2, C3, C4, C5, C6, C7, C8, C9 or the like) alkyl, C1-C10 (for example, C2, C3, C4, C5, C6, C7, C8, C9 or the like) haloalkyl, C1-C10 (for example, C2, C3, C4, C5, C6, C7, C8, C9 or the like) alkoxy, C6-C60 (for example, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C34, C36, C38, C40, C42, C44, C46, C48, C50, C52, C54, C56, C58 or the like) aryl and C3-C60 (for example, C4, C5, C6, C7, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C34, C36, C38, C40, C42, C44, C46, C48, C50, C52, C54, C56, C58 or the like) heteroaryl.
As described hereinbelow, in accordance with one aspect of the present disclosure, in the compound structure formed through the substitution of an arylamino group at position 2 and the substitution of a fused ring group (R) at position 6 on a naphthalene ring, an naphthalene conjugation is the longest, smallest molecular distortion formed, and a film formed through molecular evaporation has a smoother arrangement, which facilitates the internal extraction of visible light. The compound has a higher refractive index, is suitable for use as a material for a capping layer of an organic electroluminescent device, and can effectively improve the light extraction efficiency and the external quantum efficiency. Moreover, the compound has a relatively large extinction coefficient in the ultraviolet region (less than 400 nm), thereby facilitating the absorption of harmful light.
In an embodiment, R is selected from groups represented by Formula (2), Formula (3) and Formula (4):
Z1 to Z10 are each independently selected from a N atom, CH and CR1, where R1 is selected from any one or a combination of at least two of protium, deuterium, tritium, halogen, C1-C10 (for example, C2, C3, C4, C5, C6, C7, C8, C9 or the like) alkyl, C1-C10 (for example, C2, C3, C4, C5, C6, C7, C8, C9 or the like) haloalkyl, C1-C10 (for example, C2, C3, C4, C5, C6, C7, C8, C9 or the like) alkoxy, C6-C60 (for example, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C34, C36, C38, C40, C42, C44, C46, C48, C50, C52, C54, C56, C58 or the like) aryl and C3-C60 (for example, C4, C5, C6, C7, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C34, C36, C38, C40, C42, C44, C46, C48, C50, C52, C54, C56, C58 or the like) heteroaryl.
In accordance with one embodiment of the present disclosure, R is a structure where at most three rings are fused so that not only a good light extraction effect but also a high thermal stability can be achieved. A structure with too many fused rings results in thermal decomposition and poor solubility, which is unfavorable for cleaning a MASK during mass production.
In an embodiment, Z1 to Z10 are each independently selected from CH and CR1.
In an embodiment, R is selected from any one of the following groups:
# represents a linkage site of the group.
In an embodiment, R is selected from any one of the following groups:
# represents a linkage site of the group.
In one embodiment, naphthyl, anthracenyl and phenanthrenyl are linked at the preceding sites so that the molecule of the compound has a high refractive index due to the longest conjugated chain.
In an embodiment, R is selected from any one of the following groups:
where # represents a linkage site of the group.
Furthermore, in one embodiment, anthracenyl, phenanthrenyl and naphthyl are linked at the preceding particular sites so that the relative volume of the molecule can be further reduced and the refractive index of the molecule can be improved.
In an embodiment, in Formula (2), at least one of Z1 to Z10 is selected from N.
In Formula (3), at least one of Z1 to Z10 is selected from N.
In Formula (4), at least one of Z1 to Z8 is selected from N.
In accordance with another embodiment, R is a N-containing fused-ring heteroaryl group and can provide a better light-emitting effect than a fused-ring heteroaryl group containing no nitrogen since the molecular polarity is improved.
In an embodiment, R is selected from any one of the following groups:
# represents a linkage site of the group.
In an embodiment, in Formula (2), at least one of Z1 to Z10 is selected from CR1, and R1 is selected from any one or a combination of at least two of deuterium, halogen and C1-C10 haloalkyl.
In Formula (3), at least one of Z1 to Z10 is selected from CR1, and R1 is selected from any one or a combination of at least two of deuterium, halogen and C1-C10 haloalkyl.
In Formula (4), at least one of Z1 to Z8 is selected from CR1, and R1 is selected from any one or a combination of at least two of deuterium, halogen and C1-C10 haloalkyl.
“A combination of at least two” refers to that in the presence of at least two R1 in the structure, the at least two R1 may be selected from different substituents.
In another embodiment, R includes the substitution of deuterium, halogen or C1-C10 haloalkyl. A structure with the substitution of deuterium increases the lifetime of the device, and a structure with the substitution of halogen or C1-C10 haloalkyl increases the molecular polarity so that the device can have better efficiency.
In an embodiment, R is selected from any one of the following groups:
Where # represents a linkage site of the group.
In an embodiment, X and Y are each independently selected from substituted or unsubstituted C3-C60 electron withdrawing heteroaryl.
In an embodiment, X and Y are each independently selected from any one of the following substituted or unsubstituted groups:
Where # represents a linkage site of the group.
Q is selected from an O atom, a S atom and NR8.
R2 to R7 are each independently selected from any one of hydrogen, protium, deuterium, tritium, halogen, C1-C10 alkyl, C1-C10 alkoxy, C6-C60 aryl and C3-C60 heteroaryl.
The ring A is fused at any position of a benzene ring where the ring A can be fused and the ring A is selected from substituted or unsubstituted C6-C30 aromatic rings and substituted or unsubstituted C3-C30 heteroaromatic rings.
In an embodiment, X and Y are each independently selected from any one of the following groups:
Where # represents a linkage site of the group.
Q and R2 to R7 each have the same ranges as defined above.
In an embodiment, X and Y are each independently selected from any one of the following groups:
Where # represents a linkage site of the group.
R6 has the same range as defined above.
In an embodiment, Ar1 is selected from substituted or unsubstituted C6-C60 arylene, substituted or unsubstituted C3-C60 heteroarylene, substituted or unsubstituted C10-C60 fused-ring arylene and substituted or unsubstituted C6-C60 fused-ring heteroarylene, and X is selected from
Additionally and alternatively, Ar2 is selected from substituted or unsubstituted C6-C60 arylene, substituted or unsubstituted C3-C60 heteroarylene, substituted or unsubstituted C10-C60 fused-ring arylene and substituted or unsubstituted C6-C60 fused-ring heteroarylene, and Y is selected from
Where # represents a linkage site of the group.
In one embodiment, if Ar1 and Ar2 are the preceding aromatic groups, X and Y are linked to a side of a five-membered ring. This structure has the longest conjugation length and a lone pair on the N atom has the largest conjugation area so that the largest refractive index is obtained and the best device performance is achieved.
In an embodiment, Ar1 is selected from a single bond, and X is selected from
Additionally and alternatively, Ar2 is selected from a single bond, and Y is selected from
R6 has the same range as defined above.
Where # represents a linkage site of the group.
In another embodiment, if Ar1 and Ar2 are single bonds, X and Y are linked to a side of a benzene ring. This structure has a more uniform arrangement of electron clouds in the molecule than that formed by a direct linkage via R6 so that the largest refractive index is obtained and the best device performance is achieved.
In an embodiment, Ar1 and Ar2 are each independently selected from any one of phenylene, biphenylene, terphenylene, naphthylene, anthrylene, phenanthrylene, pyridinylene, pyrimidinylene, triazinylene, furylene, pyrrolidene, thienylene, quinolylene, isoquinolylene, benzofurylene and benzothienylene.
In an embodiment, Ar1 and Ar2 are each independently selected from
In one embodiment, Ar1 and Ar2 are p-phenylene. When Ar1 and Ar2 match R with a fused ring structure, the longest linear conjugated chain can be obtained so that the refractive index of the compound is further improved and device efficiency is improved.
In an embodiment, Ar1 and Ar2 are each independently selected from naphthylene and biphenylene.
In one embodiment, Ar1 and Ar2 are selected from naphthylene and biphenylene, which enable the compound to have a greater conjugation length than phenylene, thereby further improving the performance.
In an embodiment, Ar1 and Ar2 are each independently selected from
Where # represents a linkage site of the group.
In one embodiment, naphthylene and phenylene are linked through the preceding sites so that the compound has the longest linear conjugation, thereby further improving the device performance.
In an embodiment, the compound has a structure represented by Formula (2):
R, Ar1, Ar2, X and Y each have the same ranges as defined in Formula (1).
In an embodiment, at least one of P1, P2, P3, P4, P5 and P6 is selected from a deuterium atom.
When a naphthalene ring includes the substitution of at least one deuterium atom, the compound has more stable chemical properties, thereby obtaining a longer device lifetime.
In an embodiment, P2, P3, P5 and P6 are each selected from a deuterium atom.
Further, a better effect is achieved when four positions P2, P3, P5 and P6 are all substituted with deuterium atoms. This is because hydrogen at the positions of P2, P3, P5 and P6 is the most active and when these four positions are all substituted, the compound does not easily break down at a high temperature.
In an embodiment, the difference between the refractive index of the compound at a wavelength of 460 nm and the refractive index of the compound at a wavelength of 530 nm is 0.10-0.17, the difference between the refractive index of the compound at a wavelength of 530 nm and the refractive index of the compound at a wavelength of 620 nm is 0.03-0.10, and the difference between the refractive index of the compound at a wavelength of 460 nm and the refractive index of the compound at a wavelength of 620 nm is 0.15-0.40.
The compound of the present disclosure can satisfy the differences between the refractive indexes at the preceding wavelength bands, which means that a display panel prepared from the compound of the present disclosure can improve a color cast when performing display at multiple angles.
In an embodiment, a film with a thickness of 700 angstroms and prepared from the compound has an absorbance greater than 0.3 at a wavelength of 250 nm and at a wavelength of 380 nm.
Light at the wavelengths of 250 nm and 380 nm is harmful. The compound of the present disclosure can absorb light at the wavelengths of 250 nm and 380 nm to avoid damage to human eyes.
In an embodiment, the compound has any one of the following structures represented by P1 to P305:
In accordance with one aspect of the present disclosure, a material for an organic electroluminescent device is provided. The material for an organic electroluminescent device includes any one or a combination of at least two of the compound as described herein.
In accordance with another aspect of the present disclosure, an organic electroluminescent device is provided. The organic electroluminescent device includes a first electrode layer, an organic function layer and a second electrode layer which are stacked in sequence.
The organic function layer includes the material as described above.
In accordance with another aspect of the present disclosure, another organic electroluminescent device is provided. The organic electroluminescent device includes a first capping layer, a first electrode layer, an organic function layer and a second electrode layer which are stacked in sequence.
The first capping layer includes the material as described above.
When the device is a top emitting device, the first electrode layer is a cathode layer and the second electrode layer is an anode layer; when the device is a bottom emitting device, the first electrode layer is an anode layer and the second electrode layer is a cathode layer.
The compound of the present disclosure can interact with a metal in a cathode (or anode) of the device, which reduces the coupling effect between free charges on the surface of the metal and electromagnetic radiation and improves photon extraction efficiency. Meanwhile, this modifies a metal electrode and reduces the possibility of film peeling.
In an embodiment, an organic electroluminescent device provided by the present disclosure, as shown in
In an embodiment, the organic electroluminescent device further includes a second capping layer disposed on a side of the first capping layer facing away from the first electrode layer, where the second capping layer includes lithium fluoride and/or a material containing small organic molecules with a refractive index of 1.40-1.65 (for example, 1.42, 1.44, 1.46, 1.48, 1.5, 1.52, 1.54, 1.56, 1.58, 1.6, 1.62, 1.64 or the like).
The organic electroluminescent device provided by the present disclosure preferably includes two capping layers, and the compound provided by the present disclosure cooperates with lithium fluoride and/or a material containing small organic molecules with a refractive index of 1.40-1.65, which can alleviate the total reflection of light by a packaging glass, facilitate the transmission of visible light through the glass and improve the light extraction effect.
In an embodiment, the organic electroluminescent device provided by the present disclosure, as shown in
In an embodiment, the material containing small organic molecules with a refractive index of 1.40-1.65 includes, but is not limited to, any one or a combination of at least two of polyfluorocarbons, boron-containing compounds, silicon-containing compounds, oxygen-containing silicon compounds and adamantane-containing alkane compounds.
In accordance with another aspect of the present disclosure, a display panel is provided. The display panel includes the organic electroluminescent device as described herein.
In an embodiment, the display panel is a foldable display panel.
When the compound provided by the present disclosure is used in the foldable display panel for display at multiple angles, light extraction Δn is small for RGB colors, which can effectively reduce a color cast.
In accordance with another aspect of the present disclosure, a display device is provided. The display device includes the display panel as described herein.
The method for preparing the compound provided by the present disclosure is known, and those skilled in the art can select a specific synthesis method according to conventional techniques. The present disclosure provides an exemplary synthesis route but is not so limited to such synthesis described below.
The representative synthesis route of the compound of Formula (1) provided by the present disclosure is as follows:
where o-Xylene represents ortho-xylene, Toluene represents toluene, KO(t-Bu) represents potassium tert-butoxide, and [Pd(cinnamyl)Cl]2 represents palladium chloride (1-phenylallyl).
The following exemplary synthesis provides specific synthesis methods for a series of compounds. For compounds whose specific synthesis methods are not mentioned, these compounds may be synthesized by similar methods or other existing methods, which are not specifically limited in the present disclosure.
The synthesis route of Compound P91 is as follows:
A specific preparation method includes steps described below.
(1) P91-1 (0.5 mmol), P91-2 (0.75 mmol), K2CO3 (0.5 mmol), PdCl2 (5×10−4 mmol) and TPPDA (5×10−4 mmol) were added to 3 mL of o-xylene and mixed into a solution, and the solution was put in a 50 mL flask and reacted at 100° C. for 15 h. Then the solution was cooled to room temperature and slowly added with a saturated aqueous solution of MgSO4 and ethyl acetate to be extracted for three times. Then, the organic layer is passed through a rotary evaporator for the solvent to be removed and the crude product P91-3 was obtained through column chromatography.
The structure of the target product P91-3 was tested through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) (m/z) to obtain C20H14DN whose calculated value was 270.1 and measured value was 270.0.
(2) P91-3 (0.5 mmol), P91-4 (0.45 mmol), KO(t-Bu) (0.5 mmol), [Pd(cinnamyl)Cl]2 (1 mol %) and a ligand (1.0 mol %) were added to 3 mL of toluene and mixed into a solution, and the solution was put in a 50 mL flask and reacted at 60° C. for 12 h. Then the solution was cooled to room temperature and slowly added with a saturated aqueous solution of MgSO4 and ethyl acetate to be extracted for three times. Then, the organic layer is passed through a rotary evaporator for the solvent to be removed and the crude product P91-5 was obtained through column chromatography.
The structure of the target product P91-5 was tested through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) (m/z) to obtain C33H21DN2O whose calculated value was 463.2 and measured value was 463.0.
(3) P91-5 (0.5 mmol), P91-6 (0.65 mmol), KO(t-Bu) (0.65 mmol), [Pd(cinnamyl)Cl]2 (1.5 mol %) and a ligand (1.5 mol %) were added to 3 mL of toluene and mixed into a solution, and the solution was put in a 50 mL flask and reacted at 80° C. for 12 h. Then the solution was cooled to room temperature and slowly added with a saturated aqueous solution of MgSO4 and ethyl acetate to be extracted for three times. Then, the organic layer is passed through a rotary evaporator for the solvent to be removed and the crude product P91 was obtained through column chromatography.
The structure of the target product P91 was tested through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) (m/z) to obtain C50H30DN3O2 whose calculated value was 706.3 and measured value was 706.1.
Elemental analysis: theoretical value: C, 84.96, H, 4.56; N, 5.95; measured value: C, 84.95; H, 4.56; N, 5.96.
The synthesis route of Compound P92 is as follows:
A specific preparation method includes steps described below.
(1) P92-1 (0.5 mmol), P92-2 (0.75 mmol), K2CO3 (0.5 mmol), PdCl2 (5×10−4 mmol) and TPPDA (5×10−4 mmol) were added to 3 mL of o-xylene and mixed into a solution, and the solution was put in a 50 mL flask and reacted at 100° C. for 24 h. Then the solution was cooled to room temperature and slowly added with a saturated aqueous solution of MgSO4 and ethyl acetate to be extracted for three times. Then, the organic layer is passed through a rotary evaporator for the solvent to be removed and the crude product P92-3 was obtained through column chromatography.
The structure of the target product P92-3 was tested through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) (m/z) to obtain C20H13D2N whose calculated value was 271.1 and measured value was 271.0.
(2) P92-3 (0.5 mmol), P92-4 (1.5 mmol), KO(t-Bu) (0.75 mmol), [Pd(cinnamyl)Cl]2 (2 mol %) and a ligand (1.5 mol %) were added to 3 mL of toluene and mixed into a solution, and the solution was put in a 50 mL flask and reacted at 80° C. for 12 h. Then the solution was cooled to room temperature and slowly added with a saturated aqueous solution of MgSO4 and ethyl acetate to be extracted for three times. Then, the organic layer is passed through a rotary evaporator for the solvent to be removed and the crude product P92 was obtained through column chromatography.
The structure of the target product P92 was tested through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) (m/z) to obtain C58H35D2N3O2 whose calculated value was 809.3 and measured value was 809.1.
Elemental analysis: theoretical value: C, 86.01, H, 4.85; N, 5.19; measured value: C, 86.00; H, 4.85; N, 5.19.
The synthesis route of Compound P100 is as follows:
A specific preparation method specifically includes steps described below.
(1) P100-1 (0.5 mmol), P100-2 (0.75 mmol), K2CO3 (0.5 mmol), PdCl2 (5×10−4 mmol) and TPPDA (5×10−4 mmol) were added to 3 mL of o-xylene and mixed into a solution, and the solution was put in a 50 mL flask and reacted at 100° C. for 24 h. Then then solution was cooled to room temperature and slowly added with a saturated aqueous solution of MgSO4 and ethyl acetate to be extracted for three times. Then, the organic layer is passed through a rotary evaporator for the solvent to be removed and the crude product P100-3 was obtained through column chromatography.
The structure of the target product P100-3 was tested through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) (m/z) to obtain C20H9D6N whose calculated value was 275.2 and measured value was 275.1.
(2) P100-3 (0.5 mmol), P100-4 (1.5 mmol), KO(t-Bu) (0.75 mmol), [Pd(cinnamyl)Cl]2 (2 mol %) and a ligand (1.5 mol %) were added to 3 mL of toluene and mixed into a solution, and the solution was put in a 50 mL flask and reacted at 80° C. for 12 h. Then the solution was cooled to room temperature and slowly added with a saturated aqueous solution of MgSO4 and ethyl acetate to be extracted for three times. Then, the organic layer is passed through a rotary evaporator for the solvent to be removed and the crude product P100 was obtained through column chromatography.
The structure of the target product P100 was tested through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) (m/z) to obtain C46H25D6N5 whose calculated value was 659.3 and measured value was 659.2.
Elemental analysis: theoretical value: C, 83.74, H, 5.65; N, 10.61; measured value: C, 83.74; H, 5.65; N, 10.61.
The synthesis route of Compound P101 is as follows:
A specific preparation method includes steps described below.
(1) P101-1 (0.5 mmol), P101-2 (0.75 mmol), K2CO3 (0.5 mmol), PdCl2 (5×10−4 mmol) and TPPDA (5×10−4 mmol) were added to 3 mL of o-xylene and mixed into a solution, and the solution was put in a 50 mL flask and reacted at 100° C. for 24 h. Then the solution was cooled to room temperature and slowly added with a saturated aqueous solution of MgSO4 and ethyl acetate to be extracted for three times. Then, the organic layer is passed through a rotary evaporator for the solvent to be removed and the crude product P101-3 was obtained through column chromatography.
The structure of the target product P101-3 was tested through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) (m/z) to obtain C20H14DN whose calculated value was 270.1 and measured value was 270.1.
(2) P101-3 (0.5 mmol), P101-4 (1.5 mmol), KO(t-Bu) (0.75 mmol), [Pd(cinnamyl)Cl]2 (2 mol %) and a ligand (1.5 mol %) were added to 3 mL of toluene and mixed into a solution, and the solution was put in a 50 mL flask and reacted at 80° C. for 12 h. Then the solution was cooled to room temperature and slowly added with a saturated aqueous solution of MgSO4 and ethyl acetate to be extracted for three times. Then, the organic layer is passed through a rotary evaporator for the solvent to be removed and the crude product P101 was obtained through column chromatography.
The structure of the target product P101 was tested through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) (m/z) to obtain C54H32DN3O2 whose calculated value was 756.3 and measured value was 756.1.
Elemental analysis: theoretical value: C, 85.69, H, 4.53; N, 5.55; measured value: C, 85.68; H, 4.53; N, 5.56.
The synthesis route of Compound P197 is as follows:
A specific preparation method includes steps described below.
(1) P197-1 (0.5 mmol), P197-2 (0.75 mmol), K2CO3 (0.5 mmol), PdCl2 (5×10−4 mmol) and TPPDA (5×10−4 mmol) were added to 3 mL of o-xylene and mixed into a solution, and the solution was put in a 50 mL flask and reacted at 100° C. for 24 h. Then the solution was cooled to room temperature and slowly added with a saturated aqueous solution of MgSO4 and ethyl acetate to be extracted for three times. Then, the organic layer is passed through a rotary evaporator for the solvent to be removed and the crude product P197-3 was obtained through column chromatography.
The structure of the target product P197-3 was tested through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) (m/z) to obtain C20H15N whose calculated value was 269.1 and measured value was 269.0.
(2) P197-3 (0.5 mmol), P197-4 (1.5 mmol), KO(t-Bu) (0.75 mmol), [Pd(cinnamyl)Cl]2 (2 mol %) and a ligand (1.5 mol %) were added to 3 mL of toluene and mixed into a solution, and the solution was put in a 50 mL flask and reacted at 80° C. for 12 h. Then the solution was cooled to room temperature and slowly added with a saturated aqueous solution of MgSO4 and ethyl acetate to be extracted for three times. Then, the organic layer is passed through a rotary evaporator for the solvent to be removed and the crude product P197 was obtained through column chromatography.
The structure of the target product P197 was tested through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) (m/z) to obtain C46H29N3O2 whose calculated value was 655.2 and measured value was 655.1.
Elemental analysis: theoretical value: C, 84.25, H, 4.46; N, 6.41; measured value: C, 84.24; H, 4.46; N, 6.42.
The synthesis route of Compound P205 is as follows:
A specific preparation method includes steps described below.
(1) P205-1 (0.5 mmol), P205-2 (0.75 mmol), K2CO3 (0.5 mmol), PdCl2 (5×10−4 mmol) and TPPDA (5×10−4 mmol) were added to 3 mL of o-xylene and mixed into a solution, and the solution was put in a 50 mL flask and reacted at 100° C. for 24 h. Then the solution was cooled to room temperature and slowly added with a saturated aqueous solution of MgSO4 and ethyl acetate to be extracted for three times. Then, the organic layer is passed through a rotary evaporator for the solvent to be removed and the crude product P205-3 was obtained through column chromatography.
The structure of the target product P205-3 was tested through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) (m/z) to obtain C24H17N whose calculated value was 319.1 and measured value was 319.0.
(2) P205-3 (0.5 mmol), P205-4 (1.5 mmol), KO(t-Bu) (0.75 mmol), [Pd(cinnamyl)Cl]2 (2 mol %) and a ligand (1.5 mol %) were added to 3 mL of toluene and mixed into a solution, and the solution was put in a 50 mL flask and reacted at 80° C. for 12 h. Then the solution was cooled to room temperature and slowly added with a saturated aqueous solution of MgSO4 and ethyl acetate to be extracted for three times. Then, the organic layer is passed through a rotary evaporator for the solvent to be removed and the crude product P205 was obtained through column chromatography.
The structure of the target product P205 was tested through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) (m/z) to obtain C50H31N3O2 whose calculated value was 705.2 and measured value was 705.1.
Elemental analysis: theoretical value: C, 85.09, H, 4.43; N, 5.95; measured value: C, 85.08; H, 4.43; N, 5.94.
The preparation methods for other compounds of the present disclosure are all similar to the preceding methods and not repeated herein. Only the characterization results of mass spectrometry and elemental analysis of some other compounds of the present disclosure are provided, which are shown in Table 1-1.
Characterization data of the compounds through proton nuclear magnetic resonance are provided in Table 1-2.
1H-NMR (400 MHz, DMSO) δ (ppm) 8.38 (d, 2H), 8.27
1H-NMR (400 MHz, DMSO) δ (ppm) 8.55 (s, 2H),8.40
1H-NMR (400 MHz, DMSO) δ (ppm) 8.80 (d, 1H), 8.27
1H-NMR (400 MHz, DMSO) δ (ppm) 8.41 (d, 2H), 8.20-
1H-NMR (400 MHz, DMSO) δ (ppm) 8.40 (d, 2H), 8.19-
1H-NMR (400 MHz, DMSO) δ (ppm) 8.42 (d, 1H), 8.36
1H-NMR (400 MHz, CDCl3) δ (ppm) 8.54 (s, 1H), 8.49
1H-NMR (400 MHz, CDCl3) δ (ppm) 8.44 (s, 1H), 8.39
1H-NMR (400 MHz, CDCl3) δ (ppm) 8.84 (d, 1H), 8.78
1H-NMR (400 MHz, CDCl3) δ (ppm) 8.81 (d, 1H), 8.84
1H-NMR (400 MHz, CDCl3) δ (ppm) 8.72 (d, 2H),8.83-
1H-NMR (400 MHz, CDCl3) δ (ppm) 8.83-8.20 (m, 5H),
1H-NMR (400 MHz, CDCl3) δ (ppm) 7.85-7.83 (m, 1H),
1H-NMR (400 MHz, CDCl3) δ (ppm) 8.43 (s, 1H), 8.32
1H-NMR (400 MHz, CDCl3) δ (ppm) 8.74 (s, 1H), 8.49
1H-NMR (400 MHz, CDCl3) δ (ppm) 8.81 (s, 1H), 8.50
1H-NMR (400 MHz, DMSO) δ (ppm) 8.39 (d, 2H), 8.18-
1H-NMR (400 MHz, DMSO) δ (ppm) 8.40 (d, 2H), 8.19-
Performance Test I Characterization of Refractive Indexes of Materials
The refractive indexes of the compounds at wavelengths of 460 nm, 530 nm and 620 nm were tested by an ellipsometer. A difference Δn1 between the refractive index at the wavelength of 460 nm and the refractive index at the wavelength of 530 nm, a difference Δn2 between the refractive index at the wavelength of 530 nm and the refractive index at the wavelength of 620 nm, and a difference Δn3 between the refractive index at the wavelength of 460 nm and the refractive index at the wavelength of 620 nm were calculated.
The results of the preceding test are shown in Table 2.
Comparative compounds C1 and C2 have the following structures:
It can be seen from Table 1 that the compounds provided by the present application satisfy that the difference between the refractive index at the wavelength of 460 nm and the refractive index at the wavelength of 530 nm is 0.10-0.17, the difference between the refractive index at the wavelength of 530 nm and the refractive index at the wavelength of 620 nm is 0.03-0.10, and the difference between the refractive index at the wavelength of 460 nm and the refractive index at the wavelength of 620 nm is 0.15-0.40. When used in the organic electroluminescent device, especially as a material for a capping layer, the compound provided by the present application can improve the color cast while achieving display at multiple angles compared with compounds C1 and C2.
Performance Test II Characterization of Absorbance of Materials
The compounds of the present disclosure were made into films with a thickness of 700 angstroms, and the absorbances of the films at a wavelength of 250 nm and at a wavelength of 380 nm were measured by an ultraviolet spectrophotometer.
The results of the preceding test are shown in Table 3.
It can be seen from Table 3 that the film prepared from the compound provided by the present disclosure has an absorbance greater than 0.3 at the wavelength of 250 nm and at the wavelength of 380 nm so that the efficient absorption of light at the wavelengths of 250 nm and 380 nm is achieved and damage to human eyes is avoided.
For a better understanding of the present disclosure, application examples of the compounds of the present disclosure are listed below. It is understood that the examples described herein are used for a better understanding of the present disclosure and are not to be construed as specific limitations to the present disclosure.
This application example provides an organic electroluminescent device which has a structure shown in
(1) A glass substrate with an indium tin oxide (ITO) anode layer 2 (with a thickness of 15 nm) was cut into a size of 50 mm×50 mm×0.7 mm, sonicated in isopropyl alcohol and deionized water for 30 min separately, and cleaned under ozone for 10 min. The cleaned substrate 1 was installed onto a vacuum deposition device.
(2) A material for a hole injection layer, Compound 2, and a p-doped material, Compound 1, were co-deposited at a doping ratio of 3% (mass ratio) by means of vacuum evaporation on the ITO anode layer 2 as a hole injection layer 3 with a thickness of 5 nm.
(3) A material for a hole transport layer, Compound 2, was deposited by means of vacuum evaporation on the hole injection layer 3 as a first hole transport layer 4 with a thickness of 100 nm.
(4) A hole transport material, Compound 3, was deposited by means of vacuum evaporation on the first hole transport layer 4 as a second hole transport layer 5 with a thickness of 5 nm.
(5) A light-emitting layer 6 with a thickness of 30 nm was deposited by means of vacuum evaporation on the second hole transport layer 5, where Compound 4 was doped as a host material with Compound 5 as a doping material at a ratio of 3% (mass ratio).
(6) An electron transport material, Compound 6, was deposited by means of vacuum evaporation on the light-emitting layer 6 as a first electron transport layer 7 with a thickness of 30 nm.
(7) An electron transport material, Compound 7, and a n-doping material, Compound 8, were co-deposited at a doping mass ratio of 1:1 by means of vacuum evaporation on the first electron transport layer 7 as a second electron transport layer 8 with a thickness of 5 nm.
(8) A magnesium-silver electrode was deposited at a ratio of 9:1 by means of vacuum evaporation on the second electron transport layer 8 as a cathode 9 with a thickness of 10 nm.
(9) Compound P1 of the present disclosure was deposited by means of vacuum evaporation on the cathode 9 as a capping layer 10 with a thickness of 100 nm.
The compounds used in the preceding steps have the following structures:
Application Examples 2-24 and Comparative Application Examples 1-2 differ from Application Example 1 only in that Compound P1 in step (9) was replaced with Compounds P11, P145, P157, P169, P197, P198, P200, P201, P203, P205, P206, P207, P208, P230, P231, P232, P277, P280, P293, P294, P295, P296, P297, C1 and C2 respectively for preparing the capping layer. All the other preparation steps are the same. For details, see Table 4.
Performance Test III Characterization of Device Performance
A performance test was performed on organic electroluminescent devices provided in Application Examples 2-24 and Comparative Application Examples 1-2 as follows.
Currents were measured with Keithley 2365A digital nanovoltmeter at different voltages for the organic electroluminescent devices and then divided by a light-emitting area so that the current densities of the organic optoelectronic devices at different voltages were obtained. The brightness and radiation energy flux density of each of the organic electroluminescent devices manufactured according to application examples and comparative application examples at different voltages were tested with Konicaminolta CS-2000 spectrometer. According to the current densities and brightness of the organic electroluminescent devices at different voltages, an operating voltage Von (V), a current efficiency CE (cd/A), an external quantum efficiency EQE(max), a color cast JNCD (30/45/60° C.) and a lifetime LT95 (which is obtained by measuring time taken for the organic electroluminescent device to reach 95% of initial brightness (under a condition of 50 mA/cm2)) at the same current density (10 mA/cm2) were obtained. The results are shown in Table 4.
It can be seen from Table 4 that when used as a material in the capping layer of the organic electroluminescent device, the compound of the present disclosure effectively reduces the color cast of the device and improves the current efficiency and the external quantum efficiency.
Compound P197 differs from Compound C1 only in that both an arylamino group and a fused ring aryl group are present as substituents on a naphthalene ring, and data shows that the organic electroluminescent device whose capping layer is made of P197 has a higher current efficiency, a higher external quantum efficiency, and a lower color cast value. Compound P296 differs from Compound C2 only in that a fused ring aryl group is present as a substituent at position 6 of the naphthalene ring, and data shows that the organic electroluminescent device whose capping layer is made of Compound P296 has a higher current efficiency, a higher external quantum efficiency, and a lower color cast value.
Compound P207 differs from Compound P197 only in that a deuterated substituent is present at position 6 of the naphthalene ring, and data shows that the organic electroluminescent device whose capping layer is made of Compound P207 has a higher lifetime.
Differences between Compounds P197, P198, P200, P201, P203, P205 and P206 are that the naphthalene ring, the phenanthrene ring or the anthracene ring have different linkage sites, and the organic electroluminescent devices whose capping layers are made of Compounds P197, P201, P203 and P205 have better device efficiency.
This application example provides an organic electroluminescent device which has a structure shown in
(1) A glass substrate with an indium tin oxide (ITO) anode layer 2 (with a thickness of 15 nm) was cut into a size of 50 mm×50 mm×0.7 mm, sonicated in isopropyl alcohol and deionized water for 30 min separately, and cleaned under ozone for 10 min. The cleaned substrate 1 was installed onto a vacuum deposition device.
(2) A material for a hole injection layer, Compound 2, and a p-doping material, Compound 1, were co-deposited at a doping ratio of 3% (mass ratio) by means of vacuum evaporation on the ITO anode layer 2 as a hole injection layer 3 with a thickness of 5 nm.
(3) A material for a hole transport layer, Compound 2, was deposited by means of vacuum evaporation on the hole injection layer 3 as a first hole transport layer 4 with a thickness of 100 nm.
(4) A hole transport material, Compound 3, was deposited by means of vacuum evaporation on the first hole transport layer 4 as a second hole transport layer 5 with a thickness of 5 nm.
(5) A light-emitting layer 6 with a thickness of 30 nm was deposited by means of vacuum evaporation on the second hole transport layer 5, where Compound 4 was doped as a host material with Compound 5 as a doping material at a ratio of 3% (mass ratio).
(6) An electron transport material, Compound 6, was deposited by means of vacuum evaporation on the light-emitting layer 6 as a first electron transport layer 7 with a thickness of 30 nm.
(7) An electron transport material, Compound 7, and an n-doping material, Compound 8, were co-deposited at a doping mass ratio of 1:1 by means of vacuum evaporation on the first electron transport layer 7 as a second electron transport layer 8 with a thickness of 5 nm.
(8) A magnesium-silver electrode was deposited at a ratio of 9:1 by means of vacuum evaporation on the second electron transport layer 8 as a cathode 9 with a thickness of 10 nm.
(9) Compound P197 of the present disclosure was deposited by means of vacuum evaporation on the cathode 9 as a first capping layer 10 with a thickness of 100 nm.
(10) A small organic molecule D1 with a low refractive index was deposited by means of vacuum evaporation on the first capping layer 10 as a second capping layer 11 with a thickness of 20 nm.
Some small organic molecules with low refractive indexes have the following structures:
Application Examples 26-35 differ from Application Example 25 only in that the small organic molecule D1 in step (10) was replaced with D2, D3, D4, D5, D6, D7, D8, D9, D10 and D11 respectively for preparing the second capping layer. All the other preparation steps are the same. Application Examples 36-38 and Comparative Application Examples 3-4 differ from Application Example 25 only in that Compound P197 in step (9) was replaced with P195, P295, P277, C1 and C2 respectively for preparing the first capping layer. For details, see Table 5.
The performance test was performed on organic electroluminescent devices provided in Application Examples 25-38 and Comparative Application Examples 3-4 by the same test method described above. The results are shown in Table 5.
It can be seen from Table 5 that compared with the use of Compound C1 or C2 with the material containing small organic molecules with a low refractive index used in the second capping layer, the use of the compound provided by the present disclosure as the material in the first capping layer with the material containing small organic molecules with a low refractive index used in the second capping layer is more conducive to improving the device efficiency, especially in terms of improving the external quantum efficiency.
It is understood that the present disclosure is not limited to the detailed method described above, which means that the implementation of the present disclosure does not depend on the detailed method described above. It should be apparent to those skilled in the art that any improvements made to the present disclosure, equivalent substitutions of various raw materials of the product, the addition of adjuvant ingredients, and the selection of specific manners, etc. in the present disclosure all fall within the protection scope and the disclosure scope of the present disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202110227782.2 | Mar 2021 | CN | national |
