A phenoxazine-like compound, preparation method and application thereof, and electroluminescent device

Abstract

The present invention belongs to the field of semiconductor technology, specifically relating to a phenoxazine-like compound, its preparation method and application, and an electroluminescent device. The present invention provides a phenoxazine-like compound having a structure as shown in Formula I. The structure of the phenoxazine-like compound provided by the present invention contains a rigid phenoxazine group, which improves the structural stability of the compound. Furthermore, the compound provided by the present invention uses the phenoxazine-like structure as a parent core to connect multiple groups. The groups in the phenoxazine-like structure have strong electronic properties, which promote cross-intersection and separation between the multiple groups, preventing free rotation of the groups, resulting in a higher density of the compound, an increased refractive index of the material, and thus an improved light extraction efficiency. Using the phenoxazine-like compound provided by the present invention as a raw material to prepare the light extraction layer of an electroluminescent device can effectively improve the light extraction efficiency of OLED devices. #imgabs0#

Description

Technical Field

[0001] The present invention belongs to the field of semiconductor technology, and in particular relates to a phenoxazine-like compound, a preparation method and application thereof, and an electroluminescent device. Background Art

[0002] With the development of science and technology, OLED display technology has been widely used in fields such as smartphones and tablets. However, there is a large gap between the external quantum efficiency and internal quantum efficiency of traditional OLED devices, resulting in low light extraction efficiency, which seriously restricts the development and application of OLED.

[0003] Currently, the main methods for improving the light extraction efficiency of OLED devices are to form wrinkles on the light extraction surface of the substrate, add photonic crystals, microlens array (MLA) structures, or add a surface light extraction layer. Although forming wrinkles or adding photonic crystals on the light extraction surface of the substrate can improve the light extraction efficiency of the OLED device, it will affect the angular distribution of the OLED radiation spectrum, thereby affecting the performance of the OLED device. Adding a surface light extraction layer on the substrate surface can improve the light extraction efficiency while ensuring the performance of the OLED device. The material used to prepare the light extraction layer is a light extraction material. The existing light extraction materials have limited effect on improving the light extraction efficiency of OLED devices. There is an urgent need to develop light extraction materials that can significantly improve the light extraction efficiency of OLED devices. Summary of the Invention

[0004] In view of this, the present invention provides a phenoxazine-like compound, a preparation method and application thereof, and an electroluminescent device. The light extraction layer of the electroluminescent device prepared with the phenoxazine-like compound provided by the present invention can effectively improve the light extraction efficiency of the OLED device.

[0005] In order to solve the above technical problems, the present invention provides a phenoxazine-like compound having a structure as shown in Formula I:

[0006]

[0007] Wherein, Z is N or -CH;

[0008] L1, L2, and L3 are independently a single bond, a substituted or unsubstituted C6-C 30 arylene or substituted or unsubstituted C5~C 30 wherein the heteroarylene group comprises nitrogen, oxygen or sulfur;

[0009] R1, R2, and R3 are independently substituted or unsubstituted C6-C 30 Aryl, a group represented by any of the structural formulas 2 to 6, or a substituted or unsubstituted C5 to C6 containing one or more heteroatoms 30wherein the heteroaryl group comprises nitrogen, oxygen or sulfur; and at least one of R1, R2 and R3 is a group having a structure represented by Formula 2, Formula 3 or Formula 4;

[0010]

[0011] Wherein, X is O or S;

[0012] X1 is O, S or NR 12 ;

[0013] L4 and L5 are independently a single bond, a substituted or unsubstituted C6-C 30 Arylene, substituted or unsubstituted C5~C 30 wherein the heteroarylene group comprises nitrogen, oxygen or sulfur;

[0014] L6 is substituted or unsubstituted C6~C 30 Arylene or substituted or unsubstituted C5~C 30 wherein the heteroarylene group comprises nitrogen, oxygen or sulfur;

[0015] R6 is cyano, C1~C 10 Alkyl, C1~C 10 Alkoxy, substituted or unsubstituted C6~C 30 Aryl or substituted or unsubstituted C5~C 30 wherein the heteroaryl group comprises nitrogen, oxygen or sulfur;

[0016] R4, R5, R7, R8 and R9 are independently hydrogen, cyano, C1-C 10 Alkyl, C1~C 10 Alkoxy, substituted or unsubstituted C6~C 30 Aryl, aryl, heteroaryl substituted amino or substituted or unsubstituted C5~C 30 wherein the heteroaryl group comprises nitrogen, oxygen or sulfur;

[0017] R 10 、R 11 、R 12 Independent for C1~C 10 Alkyl, C1~C 10 Alkoxy, substituted or unsubstituted C6~C 30 Aryl, or substituted or unsubstituted C5~C 30 wherein the heteroaryl group comprises nitrogen, oxygen or sulfur;

[0018] The substituents in the substituted aryl, substituted heteroaryl, substituted arylene and substituted heteroarylene are independently halogen, cyano, protium, deuterium, tritium, C1-C 20 Alkyl, C6~C 20 Aryl or C5~C 20 Heteroaryl.

[0019] Preferably, the phenoxazine-like compound has a structure as shown in any one of Formulas I-1 to I-4:

[0020]

[0021] Preferably, the phenoxazine-like compound has a structure as shown in any one of Formulas I-5 to I-14:

[0022]

[0023] Preferably, the phenoxazine-like compound has a structure as shown in Formula I-15:

[0024]

[0025] Preferably, the phenoxazine-like compound has a structure as shown in Formula I-16:

[0026]

[0027] Preferably, L1, L2, L3, L4, and L5 are independently a single bond, a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, a substituted or unsubstituted biphenylene group, a substituted or unsubstituted pyridinylene group, a substituted or unsubstituted carbazolylene group, a substituted or unsubstituted furanylene group, a substituted or unsubstituted pyrimidinylene group, a substituted or unsubstituted pyrazinylene group, a substituted or unsubstituted pyridazinylene group, a substituted or unsubstituted dibenzofuranylene group, a substituted or unsubstituted 9,9-dimethylfluorenylene group, a substituted or unsubstituted N-phenylcarbazolylene group, a substituted or unsubstituted quinolylene group, a substituted or unsubstituted isoquinolylene group, or a substituted or unsubstituted naphthyridinylene group;

[0028] L6 is a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, a substituted or unsubstituted biphenylene group, a substituted or unsubstituted pyridinylene group, a substituted or unsubstituted carbazolylene group, a substituted or unsubstituted furanylene group, a substituted or unsubstituted pyrimidinylene group, a substituted or unsubstituted pyrazinylene group, a substituted or unsubstituted pyridazinylene group, a substituted or unsubstituted dibenzofuranylene group, a substituted or unsubstituted 9,9-dimethylfluorenylene group, a substituted or unsubstituted N-phenylcarbazolylene group, a substituted or unsubstituted quinolylene group, a substituted or unsubstituted isoquinolylene group or a substituted or unsubstituted naphthyridinylene group;

[0029] Said R4, R5, R7, R8 and R9 are independently hydrogen atoms, deuterium, cyano, methyl, ethyl, propyl, isopropyl, tert-butyl, methoxy, ethoxy, substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted anthracenyl, substituted or unsubstituted pyridyl, substituted or unsubstituted carbazolyl, substituted or unsubstituted furyl, substituted or unsubstituted pyrimidinyl, substituted or unsubstituted thiazolyl ... substituted or unsubstituted pyrazinyl, substituted or unsubstituted pyridazinyl, substituted or unsubstituted thienyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted 9,9-dimethylfluorenyl, substituted or unsubstituted N-phenylcarbazolyl, substituted or unsubstituted quinolyl, substituted or unsubstituted isoquinolyl, substituted or unsubstituted naphthyridinyl, substituted or unsubstituted oxazolyl, substituted or unsubstituted imidazolyl, substituted or unsubstituted benzoxazolyl, or substituted or unsubstituted benzimidazolyl;

[0030] R6 is cyano, methyl, ethyl, propyl, isopropyl, tert-butyl, methoxy, ethoxy, substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted anthracenyl, substituted or unsubstituted pyridyl, substituted or unsubstituted carbazolyl, substituted or unsubstituted furyl, substituted or unsubstituted pyrimidinyl, substituted or unsubstituted pyrazinyl, substituted or unsubstituted pyridazinyl, substituted or unsubstituted thienyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted 9,9-dimethylfluorenyl, substituted or unsubstituted N-phenylcarbazolyl, substituted or unsubstituted quinolyl, substituted or unsubstituted isoquinolyl, substituted or unsubstituted naphthyridinyl, substituted or unsubstituted oxazolyl, substituted or unsubstituted imidazolyl, substituted or unsubstituted benzoxazolyl or substituted or unsubstituted benzimidazolyl;

[0031] The R 10 、R 11 、R 12 and independently methyl, ethyl, propyl, isopropyl, tert-butyl, methoxy, ethoxy, substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted anthracenyl, substituted or unsubstituted pyridinyl, substituted or unsubstituted carbazolyl, substituted or unsubstituted furanyl, substituted or unsubstituted pyrimidinyl, substituted or unsubstituted pyrazinyl, substituted or unsubstituted pyridazinyl, substituted or unsubstituted thienyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted 9,9-dimethylfluorenyl, substituted or unsubstituted N-phenylcarbazolyl, substituted or unsubstituted quinolyl, substituted or unsubstituted isoquinolyl, substituted or unsubstituted naphthyridinyl, substituted or unsubstituted oxazolyl, substituted or unsubstituted imidazolyl, substituted or unsubstituted benzoxazolyl, or substituted or unsubstituted benzimidazolyl.

[0032] The substituent in the substituted group is one or more of a cyano group, a fluorine atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a tert-butyl group, a pentyl group, a phenyl group, a pyridyl group, a biphenyl group, a naphthyl group, a naphthyridinyl group, a furyl group, a dibenzofuranyl group and a carbazolyl group.

[0033] Preferably, the phenoxazine-like compound has a structure represented by any of the following structural formulas:

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040] The present invention also provides a method for preparing the phenoxazine-like compound described in the above technical solution, comprising the following steps:

[0041] Mixing a substance having a structure represented by Formula A, a substance having a structure represented by Formula B, palladium acetate, a potassium phosphate aqueous solution, and a first organic solvent, and performing a first reflux reaction to obtain an intermediate having a structure represented by Formula M;

[0042]

[0043] The intermediate, a substance having a structure represented by Formula D, a second organic solvent, sodium tert-butoxide, tris(dibenzylideneacetone)dipalladium and tri(tert-butyl)phosphine are mixed and subjected to a second reflux reaction to obtain a phenoxazine-like compound having a structure represented by Formula I;

[0044] wherein Q is -Cl, -Br or -I.

[0045] The present invention also provides the use of the phenoxazine-like compound described in the above technical solution or the phenoxazine-like compound prepared by the preparation method described in the above technical solution in an electroluminescent device.

[0046] The present invention also provides an electroluminescent device, comprising a substrate, a first electrode layer, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer / electron transport layer, an electron injection layer, a second electrode layer and a light extraction layer stacked in sequence, wherein the light extraction layer is prepared from the phenoxazine-like compound described in the above technical solution or the phenoxazine-like compound prepared by the preparation method described in the above technical solution.

[0047] The present invention provides a phenoxazine-like compound having a structure as shown in Formula I:

[0048]

[0049] Wherein, Z is N or -CH; L1, L2, L3 are independently single bonds, substituted or unsubstituted C6~C 30 arylene or substituted or unsubstituted C5~C 30 wherein the heteroarylene group comprises nitrogen, oxygen or sulfur; R1, R2 and R3 are independently substituted or unsubstituted C6 to C 30 Aryl, a group of any structure shown in Formulas 2 to 6, or a substituted or unsubstituted C5 to C6 containing one or more heteroatoms 30 wherein the heteroaryl group comprises nitrogen, oxygen or sulfur; and at least one of R1, R2 and R3 is of formula 2, formula 3 or

[0050] A group having the structure shown in Formula 4;

[0051]

[0052] Wherein, X is O or S; X1 is O, S or NR 12 ; L4 and L5 are independently single bonds, substituted or unsubstituted C6~C 30 Arylene, substituted or unsubstituted C5~C 30 wherein the heteroarylene group comprises nitrogen, oxygen or sulfur; L6 is a substituted or unsubstituted C6~C 30 Arylene or substituted or unsubstituted C5~C 30 The heteroarylene group, wherein the heteroatom includes nitrogen, oxygen or sulfur; R6 is cyano, C1~C 10 Alkyl, C1~C 10 Alkoxy, substituted or unsubstituted C6~C 30 Aryl or substituted or unsubstituted C5~C 30 The heteroaryl group, wherein the heteroatom includes nitrogen, oxygen or sulfur; R4, R5, R7, R8 and R9 are independently hydrogen atoms, cyano groups, C1-C 10 Alkyl, C1~C 10 Alkoxy, substituted or unsubstituted C6~C 30 Aryl, aryl, heteroaryl substituted amino or substituted or unsubstituted C5~C 30 wherein the heteroaryl group comprises nitrogen, oxygen or sulfur; 10 、R 11 、R 12 Independent for C1~C10 Alkyl, C1~C 10 Alkoxy, substituted or unsubstituted C6~C 30 Aryl, or substituted or unsubstituted C5~C 30 wherein the heteroaryl group comprises nitrogen, oxygen or sulfur; wherein the substituents in the substituted aryl group, substituted heteroaryl group, substituted arylene group and substituted heteroarylene group are independently halogen, cyano, protium, deuterium, tritium, C1-C 20 Alkyl, C6~C 20 Aryl or C5~C 20 Heteroaryl. The structure of the phenoxazine-like compound of the present invention contains a phenoxazine-like rigid group, which improves the structural stability of the compound. At the same time, the compound provided by the present invention uses a phenoxazine-like structure as a parent core to connect multiple groups. The groups of the phenoxazine-like structure have strong electronic properties, which promote the cross-intersection and separation of the multiple groups, preventing the groups from rotating freely, giving the compound a higher density and increasing the refractive index of the material. A higher refractive index also results in a higher light extraction rate. Using the phenoxazine-like compound provided by the present invention as a raw material to prepare the light extraction layer of an electroluminescent device can effectively improve the light extraction efficiency of the OLED device. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 Schematic diagram of the structure of the electroluminescent device prepared in the embodiment, wherein 1 is a substrate, 2 is an anode layer, 3 is a hole injection layer, 4 is a hole transport layer, 5 is an electron blocking layer, 6 is a light-emitting layer, 7 is a hole blocking layer / electron transport layer, 8 is an electron injection layer, 9 is a cathode layer, and 10 is a light extraction layer. DETAILED DESCRIPTION

[0054] The present invention provides a phenoxazine-like compound having a structure as shown in Formula I:

[0055]

[0056] In the present invention, the phenoxazine-like compound preferably has a structure as shown in any one of Formulas I-1 to I-4:

[0057]

[0058] In the present invention, when a substituent group is attached to Z, Z is C.

[0059] In the present invention, the phenoxazine-like compound preferably has a structure as shown in any one of Formulas I-5 to I-14:

[0060]

[0061]

[0062] In the present invention, the phenoxazine-like compound preferably has a structure as shown in Formula I-15:

[0063]

[0064] In the present invention, the phenoxazine-like compound preferably has a structure as shown in Formula I-16:

[0065]

[0066] In the present invention, Z is N or -CH, preferably -CH. In the present invention, when a substituent group is attached to Z, Z is C.

[0067] In the present invention, L1, L2, and L3 are independently a single bond, a substituted or unsubstituted C6-C 30 arylene or substituted or unsubstituted C5~C 30 a single bond, a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, a substituted or unsubstituted biphenylene group, a substituted or unsubstituted pyridinylene group, a substituted or unsubstituted carbazolylene group, a substituted or unsubstituted furanylene group, a substituted or unsubstituted pyrimidinylene group, a substituted or unsubstituted pyrazinylene group, a substituted or unsubstituted pyridazinylene group, a substituted or unsubstituted dibenzofuranylene group, a substituted or unsubstituted 9,9-dimethylfluorenylene group, a substituted or unsubstituted N-phenylcarbazolylene group, a substituted or unsubstituted quinolylene group, a substituted or unsubstituted isoquinolylene group or a substituted or unsubstituted naphthyridinylene group.

[0068] In the present invention, R1, R2, and R3 are independently substituted or unsubstituted C6 to C 30 Aryl, a group of any structure shown in Formulas 2 to 6, or a substituted or unsubstituted C5 to C6 containing one or more heteroatoms 30 In the present invention, at least one of R1, R2 and R3 is a group having a structure represented by Formula 2, Formula 3 or Formula 4.

[0069]

[0070] In the present invention, X is O or S, preferably O.

[0071] In the present invention, X1 is O, S or NR 12 In the present invention, R 12 Preferably C1~C 10 Alkyl, C1~C 10 Alkoxy, substituted or unsubstituted C6~C 30 Aryl, or substituted or unsubstituted C5~C 30and substituted or unsubstituted heteroaryl, more preferably methyl, ethyl, propyl, isopropyl, tert-butyl, methoxy, ethoxy, substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted anthracenyl, substituted or unsubstituted pyridyl, substituted or unsubstituted carbazolyl, substituted or unsubstituted furyl, substituted or unsubstituted pyrimidinyl, substituted or unsubstituted pyrazinyl, substituted or unsubstituted pyridazinyl, substituted or unsubstituted thienyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted 9,9-dimethylfluorenyl, substituted or unsubstituted N-phenylcarbazolyl, substituted or unsubstituted quinolyl, substituted or unsubstituted isoquinolyl, substituted or unsubstituted naphthyridinyl, substituted or unsubstituted oxazolyl, substituted or unsubstituted imidazolyl, substituted or unsubstituted benzoxazolyl, or substituted or unsubstituted benzimidazolyl.

[0072] In the present invention, L4 and L5 are independently a single bond, a substituted or unsubstituted C6-C 30 Arylene, substituted or unsubstituted C5~C 30 The heteroarylene group is preferably a single bond, a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, a substituted or unsubstituted biphenylene group, a substituted or unsubstituted pyridinylene group, a substituted or unsubstituted carbazolylene group, a substituted or unsubstituted furanylene group, a substituted or unsubstituted pyrimidinylene group, a substituted or unsubstituted pyrazinylene group, a substituted or unsubstituted pyridazinylene group, a substituted or unsubstituted dibenzofuranylene group, a substituted or unsubstituted 9,9-dimethylfluorenylene group, a substituted or unsubstituted N-phenylcarbazolylene group, a substituted or unsubstituted quinolylene group, a substituted or unsubstituted isoquinolylene group or a substituted or unsubstituted naphthyridinylene group.

[0073] In the present invention, L6 is a substituted or unsubstituted C6 to C 30 Arylene or substituted or unsubstituted C5~C 30 The heteroarylene group is preferably a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, a substituted or unsubstituted biphenylene group, a substituted or unsubstituted pyridinylene group, a substituted or unsubstituted carbazolylene group, a substituted or unsubstituted furanylene group, a substituted or unsubstituted pyrimidinylene group, a substituted or unsubstituted pyrazinylene group, a substituted or unsubstituted pyridazinylene group, a substituted or unsubstituted dibenzofuranylene group, a substituted or unsubstituted 9,9-dimethylfluorenylene group, a substituted or unsubstituted N-phenylcarbazolylene group, a substituted or unsubstituted quinolylene group, a substituted or unsubstituted isoquinolylene group or a substituted or unsubstituted naphthyridinylene group.

[0074] In the present invention, R6 is cyano, C1-C 10 Alkyl, C1~C 10 Alkoxy, substituted or unsubstituted C6~C30 Aryl or substituted or unsubstituted C5~C 30 The heteroaryl group is preferably a cyano group, a methyl group, an ethyl group, a propyl group, an isopropyl group, a tert-butyl group, a methoxy group, an ethoxy group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted anthracenyl group, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted furyl group, a substituted or unsubstituted pyrimidinyl group, a substituted or unsubstituted pyrazinyl group, a substituted or unsubstituted pyridazinyl group, a substituted or unsubstituted thienyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted 9,9-dimethylfluorenyl group, a substituted or unsubstituted N-phenylcarbazolyl group, a substituted or unsubstituted quinolyl group, a substituted or unsubstituted isoquinolyl group, a substituted or unsubstituted naphthyridinyl group, a substituted or unsubstituted oxazolyl group, a substituted or unsubstituted imidazolyl group, a substituted or unsubstituted benzoxazolyl group, or a substituted or unsubstituted benzimidazolyl group.

[0075] In the present invention, R4, R5, R7, R8 and R9 are independently hydrogen atoms, cyano groups, C1-C 10 Alkyl, C1~C 10 Alkoxy, substituted or unsubstituted C6~C 30 Aryl, aryl, heteroaryl substituted amino or substituted or unsubstituted C5~C 30 The heteroaryl group is preferably a hydrogen atom, deuterium, cyano, methyl, ethyl, propyl, isopropyl, tert-butyl, methoxy, ethoxy, substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted anthracenyl, substituted or unsubstituted pyridyl, substituted or unsubstituted carbazolyl, substituted or unsubstituted furyl, substituted or unsubstituted pyrimidinyl, substituted or unsubstituted pyrazinyl, substituted or unsubstituted pyridazinyl, substituted or unsubstituted thienyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted 9,9-dimethylfluorenyl, substituted or unsubstituted N-phenylcarbazolyl, substituted or unsubstituted quinolyl, substituted or unsubstituted isoquinolyl, substituted or unsubstituted naphthyridinyl, substituted or unsubstituted oxazolyl, substituted or unsubstituted imidazolyl, substituted or unsubstituted benzoxazolyl or substituted or unsubstituted benzimidazolyl.

[0076] In the present invention, R 10 、R 11 Independent for C1~C 10 Alkyl, C1~C 10 Alkoxy, substituted or unsubstituted C6~C 30 Aryl, or substituted or unsubstituted C5~C 30The heteroaryl group is preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, a tert-butyl group, a methoxy group, an ethoxy group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted anthracenyl group, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted furyl group, a substituted or unsubstituted pyrimidinyl group, a substituted or unsubstituted pyrazinyl group, a substituted or unsubstituted pyridazinyl group, a substituted or unsubstituted thienyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted 9,9-dimethylfluorenyl group, a substituted or unsubstituted N-phenylcarbazolyl group, a substituted or unsubstituted quinolyl group, a substituted or unsubstituted isoquinolyl group, a substituted or unsubstituted naphthyridinyl group, a substituted or unsubstituted oxazolyl group, a substituted or unsubstituted imidazolyl group, a substituted or unsubstituted benzoxazolyl group, or a substituted or unsubstituted benzimidazolyl group.

[0077] In the present invention, the heteroatom in the heteroarylene group or heteroaryl group includes nitrogen, oxygen or sulfur, preferably oxygen or sulfur.

[0078] In the present invention, the substituents in the substituted aryl, substituted heteroaryl, substituted arylene, and substituted heteroarylene are independently halogen, cyano, protium, deuterium, tritium, C1-C 20 Alkyl, C6~C 20 Aryl or C5~C 20 Heteroaryl.

[0079] In the present invention, the phenoxazine-like compound preferably has a structure represented by any of the following structural formulas:

[0080]

[0081]

[0082]

[0083]

[0084]

[0085]

[0086] More preferably

[0087]

[0088] The present invention also provides a method for preparing the phenoxazine-like compound described in the above technical solution, comprising the following steps:

[0089] Mixing a substance having a structure represented by Formula A, a substance having a structure represented by Formula B, palladium acetate, a potassium phosphate aqueous solution, and a first organic solvent, and performing a first reflux reaction to obtain an intermediate having a structure represented by Formula M;

[0090]

[0091] The intermediate, a substance having a structure represented by Formula D, a second organic solvent, sodium tert-butoxide, tris(dibenzylideneacetone)dipalladium and tri(tert-butyl)phosphine are mixed and subjected to a second reflux reaction to obtain a phenoxazine-like compound having a structure represented by Formula I;

[0092] wherein Q is -Cl, -Br or -I.

[0093] The present invention mixes a substance having a structure represented by Formula A, a substance having a structure represented by Formula B, palladium acetate, a potassium phosphate aqueous solution, and a first organic solvent, and performs a first reflux reaction to obtain an intermediate having a structure represented by Formula M. In the present invention, the mixing preferably includes the following steps:

[0094] A substance having a structure represented by Formula A, a substance having a structure represented by Formula B, a first organic solvent, and palladium acetate are first mixed to obtain a first mixed solution;

[0095] A potassium phosphate aqueous solution is added to the first mixed solution.

[0096] The present invention first mixes a substance having a structure shown in formula A, a substance having a structure shown in formula B, a first organic solvent and palladium acetate to obtain a first mixed solution. In the present invention, the first organic solvent is preferably N,N-dimethylformamide (DMF). The present invention has no special limitation on the amount of the first organic solvent, as long as the material can be completely dissolved. In the present invention, the molar ratio of the substance having the structure shown in formula A to the substance having the structure shown in formula B is preferably 1:2 to 2.5, more preferably 1:2.2 to 2.3. In the present invention, the palladium acetate (Pb(OAc)2) is a reaction catalyst. In the present invention, the molar ratio of the substance having the structure shown in formula A to palladium acetate is preferably 1:0.01 to 0.03.

[0097] In the present invention, the first mixing is preferably performed under stirring conditions. The present invention has no particular limitation on the stirring, as long as the mixture can be mixed uniformly.

[0098] After obtaining the first mixed solution, the present invention adds a potassium phosphate aqueous solution to the first mixed solution. In the present invention, the molar concentration of the potassium phosphate (K3PO4) aqueous solution is preferably 0.0098 to 0.012 mol / mL, more preferably 0.01 mol / mL. In the present invention, the volume ratio of the molar amount of the substance having the structure shown in Formula A to the potassium phosphate aqueous solution is preferably 0.02 mol:2.8 to 3.2 mL, more preferably 0.02 mol:3 mL. In the present invention, the addition of the potassium phosphate aqueous solution is preferably accompanied by stirring. The present invention has no special limitation on the stirring, as long as it can be mixed evenly.

[0099] In the present invention, the temperature of the first reflux reaction is preferably 140-160° C., more preferably 150° C.; the time of the first reflux reaction is preferably 9-11 hours, more preferably 10 hours. The present invention preferably uses the spot plate method to determine the endpoint of the first reflux reaction.

[0100] In the present invention, the first reflux reaction is preferably carried out under a protective atmosphere, and the protective atmosphere is preferably nitrogen or argon, more preferably nitrogen.

[0101] In the present invention, the reaction equation of the first reflux reaction is shown in Formula 1:

[0102]

[0103] In the present invention, after the first reflux reaction, the method preferably further includes: cooling the system after the first reflux reaction and mixing it with water, filtering the mixture obtained by mixing, concentrating the filtrate obtained by filtration, and purifying it through a silica gel column to obtain an intermediate having a structure shown in Formula M. In the present invention, the cooling is preferably air cooling, and the temperature of the system after the cooling is preferably 20-35°C, more preferably 25-30°C. The present invention has no special requirements for the filtration, and conventional methods in the field can be used. In the present invention, the concentration is preferably carried out in a vacuum drying oven. The present invention removes most of the solvent in the filtrate through concentration, and the present invention has no special requirements for the time of the concentration, as long as most of the solvent in the filtrate can be removed. The present invention has no special requirements for the method of passing through the silica gel column, and conventional methods in the field can be used.

[0104] After obtaining the intermediate, the present invention mixes the intermediate, a substance having a structure represented by Formula D, a second organic solvent, sodium tert-butoxide, tris(dibenzylideneacetone)dipalladium, and tri(tert-butyl)phosphine to conduct a second reflux reaction to obtain a phenoxazine-like compound having a structure represented by Formula I. In the present invention, Q in Formula D is preferably -Cl, -Br, or -I, more preferably -Br. In the present invention, the mixing preferably includes the following steps:

[0105] mixing the intermediate, the substance having the structure represented by Formula D, and a second organic solvent to obtain a second mixed solution;

[0106] Sodium tert-butoxide, tris(dibenzylideneacetone)dipalladium and tri(tert-butyl)phosphine are added to the second mixed melt.

[0107] The present invention mixes the intermediate, the substance having the structure shown in Formula D and the second organic solvent to obtain a second mixed solution. In the present invention, the second organic solvent is preferably toluene. The present invention has no special requirements for the amount of the second organic solvent, as long as the material can be completely dissolved. In the present invention, the molar ratio of the intermediate and the substance having the structure shown in Formula D is preferably 1:1 to 1.2, more preferably 1:1.2. In the present invention, the mixing is preferably carried out under stirring conditions. The present invention has no special restrictions on the stirring, as long as uniform mixing can be achieved.

[0108] After obtaining the second mixed solution, the present invention adds sodium tert-butoxide, tris(dibenzylideneacetone)dipalladium and tri(tert-butyl)phosphine to the second mixed solution. In the present invention, the molar ratio of the intermediate to sodium tert-butoxide is preferably 1:3 to 3.5, more preferably 1:3.

[0109] In the present invention, the temperature of the second reflux reaction is preferably 100-110°C, more preferably 105°C; the time of the second reflux reaction is preferably 22-26 hours, more preferably 24 hours. The endpoint of the second reflux reaction is preferably determined by the spot plate method.

[0110] In the present invention, the second reflux reaction is preferably carried out under a protective atmosphere, and the protective atmosphere is preferably nitrogen or argon, more preferably nitrogen.

[0111] In the present invention, after the second reflux reaction, the method preferably further includes: cooling the system after the second reflux reaction and filtering it, and subjecting the filtrate obtained by filtration to rotary evaporation and then passing it through a silica gel column to obtain a phenoxazine-like compound having a structure shown in Formula I. In the present invention, the cooling is preferably air cooling, and the temperature of the system after the cooling is preferably 20 to 35°C, more preferably 25 to 30°C. The present invention has no special requirements for the filtration, and conventional methods in the art can be used. The present invention removes most of the solvent in the system through rotary evaporation, and the present invention has no special requirements for rotary evaporation, and conventional methods in the art can be used. The present invention has no special requirements for the method of passing through the silica gel column, and conventional methods in the art can be used. In the present invention, the silica gel column is preferably a neutral silica gel column.

[0112] The present invention also provides the use of the phenoxazine-like compound described in the above technical solution or the phenoxazine-like compound prepared by the preparation method described in the above technical solution in an electroluminescent device.

[0113] The present invention also provides an electroluminescent device, comprising a substrate, a first electrode layer, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer / electron transport layer, an electron injection layer, a second electrode layer and a light extraction layer stacked in sequence;

[0114] The light extraction layer is prepared from the phenoxazine-like compound described in the above technical solution or the phenoxazine-like compound prepared by the preparation method described in the above technical solution.

[0115] In the present invention, the electroluminescent device includes a substrate. The substrate is preferably a transparent substrate or an opaque substrate. The transparent substrate is preferably glass or transparent plastic, more preferably glass; the opaque substrate is preferably a silicon substrate. The present invention determines the use of the substrate based on its mechanical strength, thermal stability, transparency, surface smoothness, and water resistance.

[0116] In the present invention, the electroluminescent device includes a first electrode layer. In the present invention, the first electrode in the first electrode layer is preferably an anode. In the present invention, the first electrode is preferably a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. In the present invention, when the first electrode is a transmissive electrode, the first electrode is preferably formed of a transparent metal oxide; the transparent metal oxide is preferably indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), or indium tin zinc oxide (ITZO). In the present invention, when the first electrode is a semi-transmissive electrode or a reflective electrode, the first electrode is preferably one or more of Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, and Cr. In the present invention, the thickness of the first electrode layer is preferably 50 to 500 nm.

[0117] In the present invention, the electroluminescent device includes a hole injection layer. In the present invention, the thickness of the hole injection layer is preferably 5 to 100 nm. The present invention has no particular limitation on how to obtain the hole injection layer, and conventional methods in the art can be used.

[0118] In the present invention, the electroluminescent device includes a hole transport layer. In the present invention, the thickness of the hole transport layer is preferably 5 to 200 nm. The present invention has no particular limitation on how to obtain the hole transport layer, and conventional methods in the art can be used.

[0119] In the present invention, the electroluminescent device includes an electron blocking layer. In the present invention, the thickness of the electron blocking layer is preferably 5 to 200 nm. The present invention has no particular limitation on how to obtain the electron blocking layer, and conventional methods in the art can be used.

[0120] In the present invention, the electroluminescent device includes a light-emitting layer. In the present invention, the light-emitting layer preferably includes a host material and a dopant material. The host material is a common green light-emitting host material in the art, and the dopant material is a common dopant material in the art. In the present invention, the host material is preferably a single host material or a dual host material. In the present invention, the thickness of the light-emitting layer is preferably 5 to 50 nm. The thickness of the light-emitting layer can be adjusted to optimize luminous efficiency and driving voltage.

[0121] In the present invention, the electroluminescent device includes a hole-blocking layer / electron-transporting layer. In the present invention, the hole-blocking layer / electron-transporting layer material is a material that readily accepts electrons from the cathode and transfers the received electrons to the light-emitting layer, and has high electron mobility. As the electron-transporting layer of the organic electroluminescent device of the present invention, electron-transporting layer materials known in the prior art for organic electroluminescent devices can be used. In the present invention, the thickness of the hole-blocking layer / electron-transporting layer is preferably 10 to 80 nm.

[0122] In the present invention, the electroluminescent device includes an electron injection layer. In the present invention, the electron injection layer material is preferably a material with a low work function, allowing electrons to be easily injected into the organic functional material layer. As the electron injection layer material of the organic electroluminescent device of the present invention, any electron injection layer material known in the art for use in organic electroluminescent devices can be used. In the present invention, the thickness of the electron injection layer is preferably 0.1 to 5 nm.

[0123] In the present invention, the electroluminescent device includes a second electrode layer. In the present invention, the second electrode in the second electrode layer is preferably a cathode. In the present invention, the second electrode is preferably a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. When the second electrode is a transmissive electrode, the second electrode preferably includes Li, Yb, Ca, LiF / Ca, LiF / Al, Al, Mg, BaF, Ba, Ag, or a compound or mixture thereof; when the second electrode is a semi-transmissive electrode or a reflective electrode, the second electrode preferably includes Ag, Mg, Yb, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, or a compound or mixture thereof. In the present invention, the thickness of the second electrode layer preferably depends on the material used.

[0124] In the present invention, the electroluminescent device includes a light extraction layer. In the present invention, the thickness of the light extraction layer is preferably 20 to 100 nm, more preferably 30 to 80 nm.

[0125] The present invention has no special requirements for the preparation method of the electroluminescent device, and conventional methods in the art can be used. The present invention preferably uses vacuum deposition, vacuum evaporation, spin coating, casting, LB method, inkjet printing, laser printing or LITI method to prepare the electroluminescent device.

[0126] In order to further illustrate the present invention, the technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0127] Example 1

[0128] Under nitrogen protection, 0.02 mol of raw material A1, 0.044 mol of raw material B1, and 0.0002 mol of palladium acetate were dissolved in 150 ml of DMF with stirring to obtain a first mixed solution; 3 mL of a 0.01 mol / mL K3PO4 aqueous solution was added to the first mixed solution, and a first reflux reaction was carried out at 150°C for 10 hours (a sampling point plate was used to confirm the completion of the reaction). After the mixture was naturally cooled to 25°C, it was mixed with 100 mL of water and filtered. The filtrate obtained by filtration was concentrated in a vacuum drying oven and purified on a silica gel column to obtain intermediate M1;

[0129] Under nitrogen protection, 0.01 mol of intermediate M1, 0.012 mol of raw material D1, and 150 ml of toluene were mixed under stirring to obtain a second mixed solution; 5×10 -5 mol Pd2(dba)3,5×10 -5 mol P(t-Bu)3, 0.03 mol sodium tert-butoxide, and a second reflux reaction at 105°C for 24h (the sampling plate showed no brominated product remaining, indicating complete reaction) and then naturally cooled to 25°C

[0130] After filtration, the filtrate obtained by evaporation was passed through a neutral silica gel column to obtain It is named as compound 1, and its elemental analysis structure (molecular formula C 56 H 33 N3O4): Calculated: C, 82.84; H, 4.10; N, 5.18; Inductively Coupled Plasma Spectrometer measured: C, 82.87; H, 4.17; N, 5.15. MS: Exact mass 811.25, found molecular weight 812.27.

[0131] The first reflux reaction equation is:

[0132]

[0133] The second reflux reaction equation is:

[0134]

[0135] The intermediate was prepared according to the method for preparing intermediate M1 in Example 1, with the differences referred to Table 1.

[0136] Table 1 Structures of raw materials and products for preparing intermediate M

[0137]

[0138] Example 2: Synthesis of Compound 2

[0139]

[0140] The phenoxazine-like compound was prepared according to the method of Example 1 and was recorded as Compound 2, except that the raw material D2 was used instead of the raw material D1; the elemental analysis structure (molecular formula C 56 H 33 N3O4): Calculated values: C, 82.84; H, 4.10; N, 5.18; measured by inductively coupled plasma spectrometry: C, 82.88; H, 4.16; N, 5.14. MS: Exact mass 811.25, found molecular weight 812.26.

[0141] Example 3: Synthesis of Compound 23

[0142]

[0143] The phenoxazine-like compound was prepared according to the method of Example 1 and was recorded as Compound 23. The difference was that the raw material D3 was used instead of the raw material D1; the intermediate M2 was used instead of the intermediate M1; the elemental analysis structure (molecular formula C 54 H 33 N3OS2): Calculated: C, 80.67; H, 4.14; N, 5.23; S, 7.98; ICP spectrometry measured: C, 80.69; H, 4.19; N, 5.19; S, 7.96. MS: Exact mass 803.21, found molecular weight 804.24.

[0144] Example 4: Synthesis of Compound 24

[0145]

[0146] The phenoxazine-like compound was prepared according to the method of Example 1 and was recorded as Compound 24. The difference was that the raw material D4 was used instead of the raw material D1; the intermediate M2 was used instead of the intermediate M1; the elemental analysis structure (molecular formula C 56 H 35N3OS2): Calculated: C, 81.03; H, 4.25; N, 5.06; S, 7.72; measured by ICP spectrometry: C, 81.06; H, 4.31; N, 5.02; S, 7.76. MS: Exact mass 829.22, found molecular weight 830.23.

[0147] Example 5: Synthesis of Compound 45

[0148]

[0149] The phenoxazine-like compound was prepared according to the method of Example 1 and was recorded as Compound 45. The difference was that the raw material D5 was used instead of the raw material D1; the intermediate M3 was used instead of the intermediate M1; the elemental analysis structure (molecular formula C 65 H 40 N6O3): Calculated values: C, 81.92; H, 4.23; N, 8.82; ICP spectrometry measured values: C, 81.95; H, 4.21; N, 8.87. MS: Exact mass 952.32, found molecular weight 953.36.

[0150] Example 6: Synthesis of Compound 46

[0151]

[0152] The phenoxazine-like compound was prepared according to the method of Example 1 and was recorded as Compound 46. The difference was that the raw material D6 was used instead of the raw material D1; the intermediate M3 was used instead of the intermediate M1; the elemental analysis structure (molecular formula C 68 H 44 N4O3): Calculated values: C, 84.63; H, 4.60; N, 5.81; measured by inductively coupled plasma spectrometry: C, 84.64; H, 4.63; N, 5.84. MS: Exact mass 964.34, found molecular weight 965.31.

[0153] Example 7: Synthesis of Compound 135

[0154]

[0155] The phenoxazine-like compound was prepared according to the method of Example 1 and recorded as Compound 135. The difference was that the raw material D7 was used instead of the raw material D1; the intermediate M4 was used instead of the intermediate M1; the elemental analysis structure (molecular formula C 48 H 29 N3O3): Calculated values: C, 82.86; H, 4.20; N, 6.04; ICP spectrometry measured values: C, 82.83; H, 4.17; N, 6.01. MS: Exact mass 695.22, found molecular weight 696.17.

[0156] Example 8: Synthesis of Compound 136

[0157]

[0158] The phenoxazine-like compound was prepared according to the method of Example 1 and recorded as Compound 136. The difference was that the raw material D8 was used instead of the raw material D1; the intermediate M4 was used instead of the intermediate M1; the elemental analysis structure (molecular formula C 50 H 31 N₃O₃): Calculated values: C, 83.20; H, 4.33; N, 5.82; ICP spectrometry measured values: C, 83.16; H, 4.33; N, 5.85. MS: Exact mass 721.24, found molecular weight 722.19.

[0159] Example 9: Synthesis of Compound 157

[0160]

[0161] The phenoxazine-like compound was prepared according to the method of Example 1 and recorded as Compound 157. The difference was that the raw material D9 was used instead of the raw material D1; the intermediate M5 was used instead of the intermediate M1; the elemental analysis structure (molecular formula C 50 H 31 N3OS2): Calculated: C, 79.66; H, 4.14; N, 5.57; S, 8.50; ICP spectrometry measured: C, 79.62; H, 4.19; N, 5.54; S, 8.51. MS: Exact mass 753.19, found molecular weight 754.18.

[0162] Example 10: Synthesis of Compound 158

[0163]

[0164] The phenoxazine-like compound was prepared according to the method of Example 1 and recorded as Compound 158. The difference was that the raw material D10 was used instead of the raw material D1; the intermediate M5 was used instead of the intermediate M1; the elemental analysis structure (molecular formula C 53 H 35 N3OS2): Calculated: C, 80.17; H, 4.44; N, 5.29; S, 8.08; ICP spectrometry measured: C, 80.14; H, 4.48; N, 5.27; S, 8.03. MS: Exact mass 793.22, found molecular weight 794.13.

[0165] Example 11: Synthesis of Compound 281

[0166]

[0167] The phenoxazine-like compound was prepared according to the method of Example 1 and recorded as Compound 281. The difference was that the raw material D11 was used instead of the raw material D1; the intermediate M6 was used instead of the intermediate M1; the elemental analysis structure (molecular formula C 61 H 36 N2O4): Calculated: C, 85.10; H, 4.21; N, 3.25; Inductively Coupled Plasma Spectrometer measured: C, 85.14; H, 4.24; N, 3.22. MS: Exact mass 860.27, found molecular weight 861.21.

[0168] Example 12: Synthesis of Compound 282

[0169]

[0170] The phenoxazine-like compound was prepared according to the method of Example 1 and recorded as Compound 282. The difference was that the raw material D12 was used instead of the raw material D1; the intermediate M7 was used instead of the intermediate M1; the elemental analysis structure (molecular formula C 61 H 36 N2O4): Calculated values: C, 85.10; H, 4.21; N, 3.25; ICP spectrometry measured values: C, 85.14; H, 4.25; N, 3.22. MS: Exact mass 860.27, found molecular weight 861.22.

[0171] The electroluminescent device was prepared as follows:

[0172] a) Using transparent glass as substrate layer 1, the anode layer 2 (Ag (100 nm)) was cleaned by ultrasonic cleaning using isopropyl alcohol and deionized water for 10 minutes, then irradiated with ultraviolet light for 10 minutes, and then exposed to ozone for cleaning;

[0173] b) On the anode layer 2, HAT-CN was deposited by vacuum evaporation to a thickness of 10 nm as a hole injection layer 3;

[0174] c) On the hole injection layer 3, HT-1 was evaporated to a thickness of 140 nm by vacuum evaporation to serve as the hole transport layer 4;

[0175] d) On the hole transport layer 4, EB-1 was evaporated to a thickness of 30 nm by vacuum evaporation to serve as the electron blocking layer 5;

[0176] e) depositing a 40 nm thick light-emitting layer 6 on the electron blocking layer 5, using GH-2 and GH-1 as host materials and GD-1 as a dopant material, with a mass ratio of GH-2, GH-1, and GD-1 being 45:45:10;

[0177] f) On the light-emitting layer 6, ET-1 and Liq were vacuum-deposited in a mass ratio of 1:1 to form a hole-blocking layer / electron-transporting layer 7. The thickness of the hole-blocking layer / electron-transporting layer 7 was 40 nm.

[0178] g) On the hole blocking layer / electron transport layer 7, LiF is vacuum-deposited to a thickness of 1 nm as the electron injection layer 8;

[0179] h) On the electron injection layer 8, Mg and Ag are vacuum-deposited in a mass ratio of 1:9 as a cathode layer 9, and the thickness of the cathode layer 9 is 15 nm;

[0180] i) Vacuum evaporating a light extraction layer material to a thickness of 70 nm on the cathode layer 9 to form a light extraction layer 10, thereby obtaining an electroluminescent device; the light extraction layer material is the phenoxazine-like compound prepared in Examples 1 to 12 or Ref-1;

[0181] Among them, HAT-CN is HT-1 EB-1 is GD-1 is ET-1 GH-1 is GH-2 is Liq is Ref-1 is

[0182] The structure of electroluminescent device is as follows Figure 1 As shown, 1 is a substrate, 2 is an anode layer, 3 is a hole injection layer, 4 is a hole transport layer, 5 is an electron blocking layer, 6 is a light emitting layer, 7 is a hole blocking layer / electron transport layer, 8 is an electron injection layer, 9 is a cathode layer, and 10 is a light extraction layer;

[0183] Electroluminescent devices were prepared using the phenoxazine-like compounds prepared in Examples 1 to 12 and Ref-1 as light extraction layer materials. The differences are shown in Table 2.

[0184] Table 2 Composition of the prepared electroluminescent device

[0185]

[0186]

[0187] The IVL (current-voltage-luminance) test system was used at 10 mA / cm 2 The current efficiency of the prepared electroluminescent device was tested at a current density of , and the test results are listed in Table 3.

[0188] Table 3 Performance of the prepared electroluminescent devices

[0189]

[0190] From the results in Table 3, it can be seen that the present invention uses a phenoxazine-like compound as the light extraction layer of the OLED light-emitting device, which can effectively improve the light extraction efficiency of the OLED light-emitting device.

[0191] Although the above embodiment provides a detailed description of the present invention, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the scope of protection of the present invention.

Claims

1. A phenoxazine-like compound, characterized in that: Having the structure shown in any one of Formula I, Compounds 1-2, Compounds 23-24, Compounds 45-46, Compounds 135-136, and Compounds 157-158: Formula I; Wherein, Z is -CH; L1, L2, and L3 are each unsubstituted phenylene; R1 and R2 are groups of the structure shown in Formula 5, and R3 is a group of the structure shown in Formula 2; 、 ； wherein X is O or S, R4 is H, R5 is H or unsubstituted phenyl, X1 is O, R8 is H, and R9 is H; 、 、 、 、 、 、 、 、 、 。 2. The phenoxazine compound according to claim 1, characterized in that The phenoxazine-like compound has a structure shown in any of the following structural formulas: 。 3. Use of the phenoxazine-like compound according to claim 1 or 2 as a light extraction layer in an electroluminescent device.

4. An electroluminescent device comprising a substrate, a first electrode layer, a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer / electron transport layer, an electron injection layer, a second electrode layer and a light extraction layer stacked in sequence, characterized in that: The light extraction layer is prepared from the phenoxazine-like compound according to claim 1 or 2.

Images