A compound, an organic electroluminescent device and a display device containing the same

Abstract

The present invention provides a compound, an organic electroluminescent device and a display device containing the compound, and relates to the technical field of organic electroluminescent materials. The organic electroluminescent device using the compound as an electron transport material has a lower driving voltage, a higher current efficiency and a longer lifespan.

Description

Technical Field

[0001] The invention belongs to the technical field of organic electroluminescent materials, and in particular relates to a compound, an organic electroluminescent device and a display device containing the compound. Background Art

[0002] OLED (Organic Light Emitting Diode) is a new type of display technology with the advantages of self-luminescence, high contrast, wide viewing angle, and fast response. The development of OLED technology stems from the improvement and breakthrough of traditional liquid crystal display technology. Its characteristic is that it uses organic thin film as the light-emitting material and emits light through the flow of current under the action of an electric field.

[0003] As OLED products gradually enter the market, people have higher and higher requirements for the performance of such products. The current OLED materials and device structures cannot completely solve the problems of OLED product efficiency, lifespan, cost, etc. There are problems such as low luminous efficiency, high driving voltage and short service life.

[0004] Therefore, the field urgently needs to study more types of electron transport materials so that when they are used in OLED devices, they can further improve the luminous efficiency, reduce the driving voltage, and extend the service life. Summary of the invention

[0005] In view of the deficiencies of the prior art, an object of the present invention is to provide a compound, an organic electroluminescent device and a display device comprising the same.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a compound having a structural formula as described in the following formulas IA to Id:

[0008] ;

[0009] Ia Ib

[0010] ;

[0011] Ic Id

[0012] In formulas 1a to 1d, R2, R3, R b , R c Each independently selected from hydrogen, halogen, C1~C 12 Straight or branched alkyl, C3~C 12 Cycloalkyl, C1~C 12 Straight chain or branched chain alkoxy, C3~C 12 Cycloalkoxy, C1~C12 Silane, C3~C 12 Carbonyl, C3~C 12 Acyl, C3~C 12 Ester group, cyano group, amino group, C6~C 30 Aryl, C3~C 30 Any of the heteroaryl groups;

[0013] The n is an integer of 1 to 3, for example, 1, 2, or 3;

[0014] The p is an integer from 1 to 4, for example, it can be 1, 2, 3, or 4;

[0015] In formulas Ia to Id, Y1, Y2, Y3, Y4, Y5, Y6, Y7, Y8, Y9, Y 10 , Y 11 , Y 12 Each is independently CR1 or N; each R1 is independently selected from hydrogen, halogen, C1~C 12 Straight or branched alkyl, C3~C 12 Cycloalkyl, C1~C 12 Straight chain or branched chain alkoxy, C3~C 12 Cycloalkoxy, C1~C 12 Silane, C3~C 12 Carbonyl, C3~C 12 Acyl, C3~C 12 Ester group, cyano group, amino group, C6~C 30 Aryl, C3~C 30 Any of the heteroaryl groups;

[0016] In formulas IA to Id, Ar1 is selected from hydrogen, halogen, C1~C 12 Straight or branched alkyl, C3~C 12 Cycloalkyl, C1~C 12 Straight chain or branched chain alkoxy, C3~C 12 Cycloalkoxy, C1~C 12 Silane, C3~C 12 Carbonyl, C3~C 12 Acyl, C3~C 12 Ester group, cyano group, amino group, C6~C 30 Aryl, C3~C 30 Any of the heteroaryl groups;

[0017] In formulas Ⅰa to Ⅰd, L1 is selected from a single bond, a substituted or unsubstituted C1~C 12 Straight chain or branched alkylene, substituted or unsubstituted C3~C 12 Cycloalkylene, substituted or unsubstituted C1~C 12Straight chain or branched chain alkyleneoxy, substituted or unsubstituted C3~C 12 Cycloalkoxy, substituted or unsubstituted C6~C 30 Arylene, substituted or unsubstituted C3~C 30 Any of the heteroarylene groups;

[0018] In formulas IA to Id, L2 is selected from substituted or unsubstituted C6 to C 30 Arylene, substituted or unsubstituted C3~C 30 Any of the heteroarylene groups.

[0019] When the above groups have substituents, the substituents are selected from halogen, C1~C 10 Straight or branched alkyl, C3~C 12 Cycloalkyl, C2~C 10 Alkenyl, C1~C6 alkoxy or thioalkoxy, C6~C 30 Aryl, C3~C 30 Any of the heteroaryl groups.

[0020] Preferably, the compound has the structural formula described by Formula Ia or Id.

[0021] Preferably, in formulas 1a to 1d, R2 and R3 are each independently selected from hydrogen, halogen, C1~C 12 Straight or branched alkyl, C3~C 12 Cycloalkyl, cyano, C6~C 30 Aryl, C3~C 30 Any of the heteroaryl groups.

[0022] Preferably, the R b , R c For hydrogen.

[0023] Preferably, Y1, Y2, Y3, Y4, Y5, Y6, Y7, Y8, Y9, Y 10 , Y 11 , Y 12 It is CR1.

[0024] Preferably, said R1 is hydrogen.

[0025] Preferably, the compound has the structural formula described in Formula Ia-1, Ib-1, Ic-1 or Id-1:

[0026] ;

[0027] Ⅰa-1 Ⅰb-1

[0028] ;

[0029] Ⅰc-1 Ⅰd-1

[0030] In formulas Ⅰa-1 to Ⅰd-1, R2 and R3 are each independently selected from hydrogen, halogen, C1~C 12 Straight or branched alkyl, C3~C 12 Cycloalkyl, C1~C 12 Straight chain or branched chain alkoxy, C3~C 12 Cycloalkoxy, C1~C 12 Silane, C3~C 12 Carbonyl, C3~C 12 Acyl, C3~C 12 Ester group, cyano group, amino group, C6~C 30 Aryl, C3~C 30 Any of the heteroaryl groups;

[0031] In formulas Ⅰa-1 to Ⅰd-1, Ar1 is selected from hydrogen, halogen, C1~C 12 Straight or branched alkyl, C3~C 12 Cycloalkyl, C1~C 12 Straight chain or branched chain alkoxy, C3~C 12 Cycloalkoxy, C1~C 12 Silane, C3~C 12 Carbonyl, C3~C 12 Acyl, C3~C 12 Ester group, cyano group, amino group, C6~C 30 Aryl, C3~C 30 Any of the heteroaryl groups;

[0032] In formulas Ⅰa-1 to Ⅰd-1, L1 is selected from a single bond, a substituted or unsubstituted C1~C 12 Straight chain or branched alkylene, substituted or unsubstituted C3~C 12 Cycloalkylene, substituted or unsubstituted C1~C 12 Straight chain or branched chain alkyleneoxy, substituted or unsubstituted C3~C 12 Cycloalkoxy, substituted or unsubstituted C6~C 30 Arylene, substituted or unsubstituted C3~C 30 Any of the heteroarylene groups;

[0033] In formulas Ⅰa-1 to Ⅰd-1, L2 is selected from substituted or unsubstituted C6~C 30 Arylene, substituted or unsubstituted C3~C 30 Any of the heteroarylene groups.

[0034] When the above groups have substituents, the substituents are selected from halogen, C1~C 10 Straight or branched alkyl, C3~C12 Cycloalkyl, C2~C 10 Alkenyl, C1~C6 alkoxy or thioalkoxy, C6~C 30 Aryl, C3~C 30 Any of the heteroaryl groups.

[0035] Preferably, the compound has the structural formula described in Formula Ia-1 or Ib-1.

[0036] Preferably, L2 is selected from C6~C 30 Arylene, C3~C 30 Any one of the heteroarylene groups, preferably C6~C 30 The arylene group is more preferably a phenylene group.

[0037] Preferably, L1 is selected from a single bond, C6~C 30 Arylene, C3~C 30 Any of the heteroarylene groups is preferably a single bond or a phenylene group.

[0038] Preferably, Ar1 is selected from C6~C 30 Aryl, C3~C 30 Any of the heteroaryl groups.

[0039] Preferably, the R2 is selected from C6~C 30 Aryl, C3~C 30 Any of the heteroaryl groups.

[0040] Preferably, the R2 is selected from C6~C 30 Aryl.

[0041] Preferably, the R3 is selected from C6~C 30 Aryl, C3~C 30 Any of the heteroaryl groups.

[0042] Preferably, the R3 is selected from C6~C 30 Aryl.

[0043] Preferably, the compound includes any one of the following compounds:

[0044] ;

[0045] ;

[0046] ;

[0047] ;

[0048] ;

[0049] ;

[0050] ;

[0051] ;

[0052] ;

[0053] ;

[0054] ;

[0055] ;

[0056] ;

[0057] .

[0058] In a second aspect, the present invention provides an organic electroluminescent device, which comprises any one or a combination of at least two of the compounds.

[0059] Preferably, the organic electroluminescent device comprises a first electrode, a second electrode and an organic layer disposed between the first electrode and the second electrode; the material of the organic layer comprises any one or a combination of at least two of the compounds mentioned above.

[0060] Preferably, the organic layer comprises an electron transport layer; the material of the electron transport layer comprises any one or a combination of at least two of the compounds described above.

[0061] In a third aspect, the present invention provides a display device, comprising the organic electroluminescent device.

[0062] Compared with the prior art, the present invention has the following beneficial effects:

[0063] The compound of the present invention has good electron transport performance and can be used to prepare organic electroluminescent devices, especially as an electron transport material in organic electroluminescent devices, which can effectively reduce the driving voltage of organic electroluminescent devices and improve the current efficiency of organic electroluminescent devices. DETAILED DESCRIPTION

[0064] For the convenience of understanding the present invention, the present invention lists the following embodiments. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0065] 1. Synthesis of intermediate M-1:

[0066]

[0067] (1) Synthesis of intermediate M-1-1

[0068] Add 100 mmol 2-bromo-3-iodonaphthalene, 100 mmol o-nitrobenzeneboric acid, 2 mmol tetrakis(triphenylphosphine)palladium, 120 mmol potassium carbonate, 50 mL water and 300 mL dioxane into a reaction flask, react at 80 °C for 4 h under nitrogen protection, extract with dichloromethane after the reaction is complete, and concentrate to obtain intermediate M-1-1.

[0069] The mass spectrum data of the intermediate M-1-1 was tested, and the mass spectrum m / z was measured to be 326.99.

[0070] (2) Synthesis of intermediate M-1-2

[0071] 50 mmol M-1-1, 100 mmol triphenylphosphine and 150 mL o-dichlorobenzene were added to the reaction bottle and refluxed for 6 hours under nitrogen protection. After the reaction was complete, o-dichlorobenzene was distilled off and the residue was purified by column chromatography to obtain intermediate M-1-2.

[0072] The mass spectrum data of the intermediate M-1-2 was tested, and the mass spectrum m / z was measured to be 295.00.

[0073] (3) Synthesis of intermediate M-1-3

[0074] Add 40mmol M-1-2, 40mmol iodobenzene, 40mmol cuprous iodide, 80mmol o-phenanthroline, 60mmol potassium phosphate and 300mL toluene into a reaction bottle and heat to 120°C to react for 8h. After the reaction is complete, filter with diatomaceous earth, then add a mixed solvent of water and ethyl acetate for extraction, and concentrate the obtained organic phase to obtain the intermediate M-1-3.

[0075] The mass spectrum data of the intermediate M-1-3 was tested, and the mass spectrum m / z was measured to be 371.03.

[0076] (4) Synthesis of intermediate M-1-4

[0077] Add 30mmol M-1-3, 30mmol o-nitrobenzeneboric acid, 0.3mmol tetrakis(triphenylphosphine)palladium, 50mmol potassium carbonate, 10mL water and 150mL dioxane into a reaction bottle, react at 120°C for 4h under nitrogen protection, extract with dichloromethane after the reaction is complete, and concentrate to obtain intermediate M-1-4.

[0078] The mass spectrum data of intermediate M-1-4 was tested, and the mass spectrum m / z was measured to be 414.14.

[0079] (5) Synthesis of intermediate M-1

[0080] 25mmol M-1-4, 50mmol triphenylphosphine and 100mL o-dichlorobenzene were added to the reaction bottle and refluxed for 6h under nitrogen protection. After the reaction was complete, o-dichlorobenzene was distilled off and the residue was purified by column chromatography to obtain intermediate M-1.

[0081] The mass spectrum data of the intermediate M-1 was tested, and the mass spectrum m / z was measured to be 382.15.

[0082] 2. Synthesis of intermediate M-2:

[0083] The difference from the synthesis of M-1 is that iodobenzene is replaced by an equivalent amount of 1-iodonaphthalene to obtain the intermediate M-2.

[0084] The mass spectrum data of the intermediate M-2 was tested, and the mass spectrum m / z was measured to be 432.16.

[0085]

[0086] 3. Synthesis of intermediate M-3:

[0087] The difference from the synthesis of M-1 is that iodobenzene is replaced by an equivalent amount of 2-iodonaphthalene to obtain the intermediate M-3.

[0088] The mass spectrum data of intermediate M-3 was tested, and the mass spectrum m / z was measured to be 432.16.

[0089]

[0090] 4. Synthesis of intermediate M-4:

[0091] The difference from the synthesis of M-1 is that iodobenzene is replaced with an equivalent amount of 4-iodobiphenyl to obtain the intermediate M-4.

[0092] The mass spectrum data of intermediate M-4 was tested, and the mass spectrum m / z was measured to be 458.18.

[0093]

[0094] Illustratively, the following synthesis examples provide methods for preparing several specific compounds:

[0095] Synthesis example 1

[0096] Synthesis of Compound A:

[0097]

[0098] 30 mmol of intermediate M-1, 30 mmol of 2-(3-fluorophenyl)-4-phenylquinazoline, 60 mmol of cesium carbonate and 300 mL of DMF were added to a reaction bottle and heated to reflux for 5 h. After the reaction was completed, the reaction solution was poured into water and filtered. The filter cake was washed with ethanol and recrystallized with toluene to obtain compound A.

[0099] The mass spectrum data of compound A was tested, and the mass spectrum m / z was measured to be 662.25.

[0100] Synthesis example 2

[0101] Synthesis of compound B:

[0102]

[0103] Referring to the specific preparation method of compound A in Synthesis Example 1, the only difference from the preparation method of compound A is that 2-(3-fluorophenyl)-4-phenylquinazoline is replaced with an equal amount of 2-([1,1'-biphenyl]-3-yl)-3-(4-fluorophenyl)quinoxaline to obtain compound B.

[0104] The mass spectrum data of compound B was tested, and the mass spectrum m / z was measured to be 738.28.

[0105] Synthesis example 3

[0106] Synthesis of compound C:

[0107]

[0108] Referring to the specific preparation method of compound A in Synthesis Example 1, the method is different from the preparation method of compound A in that intermediate M-1 is replaced with an equivalent amount of intermediate M-2 to obtain compound C.

[0109] The mass spectrum data of compound C was tested, and the mass spectrum m / z was measured to be 712.26.

[0110] Synthesis example 4

[0111] Synthesis of compound D:

[0112]

[0113] Referring to the specific preparation method of compound B in Synthesis Example 2, the difference from the preparation method of compound B is that 2-([1,1'-biphenyl]-3-yl)-3-(4-fluorophenyl)quinoxaline is replaced with an equivalent amount of the intermediate 4-([1,1'-biphenyl]-4-yl)-2-(4-fluorophenyl)quinazoline to obtain compound D.

[0114] The mass spectrum data of compound D was tested, and the mass spectrum m / z was measured to be 814.31.

[0115] Synthesis example 5

[0116] Synthesis of compound E:

[0117]

[0118] Referring to the specific preparation method of compound A in Synthesis Example 1, the only difference from the preparation method of compound A is that intermediate M-1 is replaced with an equivalent amount of intermediate M-3 to obtain compound E.

[0119] The mass spectrum data of compound E was tested, and the mass spectrum m / z was measured to be 712.26.

[0120] Synthesis example 6

[0121] Synthesis of compound F:

[0122]

[0123] Referring to the specific preparation method of compound A in Synthesis Example 1, the method is different from the preparation method of compound A only in that intermediate M-1 is replaced with an equivalent amount of intermediate M-4 to obtain compound F.

[0124] The mass spectrum data of compound F was tested, and the mass spectrum m / z was measured to be 738.28.

[0125] Synthesis Example 7

[0126] Synthesis of compound G:

[0127]

[0128] Referring to the specific preparation method of compound B in Synthesis Example 2, the only difference from the preparation method of compound B is that intermediate M-1 is replaced with an equivalent amount of intermediate M-4 to obtain compound G.

[0129] The mass spectrum data of compound G was tested, and the mass spectrum m / z was measured to be 814.31.

[0130] Other compounds for which specific synthesis steps are not listed can be prepared by common knowledge in the art combined with the synthesis methods provided in the above embodiments.

[0131] The specific structures of some compounds used in the following device examples and device comparative examples are shown below:

[0132]

[0133] The device example uses the compound of the present application as the electron transport material in the organic electroluminescent device, and the device comparative example uses Z-1 to Z-3 as the electron transport material in the organic electroluminescent device.

[0134] The structure of the organic electroluminescent device is: ITO / NPB (40nm) / EM1 (30nm) / electron transport material (30nm) / LiF (0.5nm) / Al (150nm). Among them: ITO: indium tin oxide; NPB: N4, N4'-di(naphthalene-1-yl)-N4, N4'-diphenyl-[1,1'-biphenyl]-4,4'-diamine; EM1: 9-(naphthalene-1-yl)-10-(4-(naphthalene-1-alkyl)phenyl)anthracene; LIF: lithium fluoride; Al: aluminum flake; nm: nanometer (unit of length).

[0135] Device Example 1

[0136] The preparation process of organic electroluminescent device is as follows:

[0137] The glass substrate coated with an ITO transparent conductive layer (as an anode) is ultrasonically treated in a cleaning agent, then rinsed in deionized water, ultrasonically degreased in a mixed solvent of acetone and ethanol, baked in a clean environment until the water is completely removed, cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam to improve the properties of the surface and enhance the binding ability with the hole injection layer;

[0138] The glass substrate was placed in a vacuum chamber and evacuated to 1×10 -5 ~9×10 -3 Pa, vacuum evaporate NPB on the anode as a hole transport layer, the evaporation rate is 0.1nm / s, and the evaporation film thickness is 40nm;

[0139] Vacuum evaporate EM1 on the hole transport layer as the organic light-emitting layer of the device, with an evaporation rate of 0.1 nm / s and a total evaporation film thickness of 30 nm;

[0140] Vacuum evaporating compound A on the organic light-emitting layer as the electron transport layer of the organic electroluminescent device; the evaporation rate is 0.1 nm / s, and the total evaporation film thickness is 30 nm;

[0141] 0.5 nm of LiF and 150 nm of Al were vacuum-deposited on the electron transport layer to serve as an electron injection layer and a cathode.

[0142] The brightness, driving voltage, current efficiency and life test LT90 of the prepared organic electroluminescent device were measured.

[0143] Device Examples 2 to 7

[0144] Device Examples 2 to 7 respectively provide an organic electroluminescent device, which differs from Device Example 1 only in that the electron transport material is different (see Table 1 below for details), and other conditions are the same as those of Device Example 1.

[0145] Device Comparison Examples 1~3

[0146] Device Comparative Examples 1 to 3 respectively provide an organic electroluminescent device, which differs from Device Example 1 only in that the electron transport material is different (see Table 1 below for details), and other conditions are the same as those of Device Example 1.

[0147] Performance Testing

[0148] Test method: The OLED-1000 multi-channel accelerated aging life and light color performance analysis system produced by Hangzhou Yuanfang was used to test the driving voltage, current efficiency and life LT90 of the OLED devices provided above; LT90 refers to the time required for the brightness to drop to 90% of the original brightness while maintaining the current density at the initial brightness of 1000nit. The test items include the brightness, driving voltage and current efficiency of the organic electroluminescent device. The driving voltage, current efficiency and LT90 data are all based on a brightness of 1000cd / m 2 The relative value at the time of the test is based on the test data of comparative example Z-1. The test results of the performance of the organic electroluminescent device are shown in the following Table 1:

[0149] Table 1

[0150]

[0151] It can be seen from the data in Table 1 that, compared with the comparative example, the organic electroluminescent device prepared using the compound of the embodiment of the present application as the electron transport material has a lower driving voltage, a higher current efficiency and a longer life.

[0152] The present invention illustrates the detailed process flow of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned detailed process flow, that is, it does not mean that the present invention must rely on the above-mentioned detailed process flow to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A compound, characterized in that The compound is the following compound B: 。 2. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises a first electrode, a second electrode and an organic layer disposed between the first electrode and the second electrode; the organic layer comprises an electron transport layer; and the material of the electron transport layer comprises the compound as claimed in claim 1.

3. A display device, characterized in that: The display device comprises the organic electroluminescent device as claimed in claim 2.

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