Amino compound and organic electroluminescent device

Abstract

The invention provides an amino compound which is shown as a formula I, wherein R1, R2, R3, R4 and R5 in the formula I are independently selected from deuterium, substituted or unsubstituted C1-C5 alkyl, substituted or unsubstituted C3-C6 cycloalkyl, substituted or unsubstituted C6-C20 aryl and substituted or unsubstituted C6-C20 heteroaryl, and substituent groups are selected from deuterium, fluorine, cyano, C1-C5 alkyl and C3-C6 cycloalkyl; a and d are independently selected from integers of 0-5, and b, c and e are independently selected from integers of 0-4. According to the present invention, deuteration is performed on the active sites of the respective structures of the compounds so as to provide good thermal stability, good chemical stability and good photoelectric stability; and meanwhile, the molecular weight of the compound is effectively controlled while the stability of the compound is improved through deuteration, so that the evaporation temperature and sublimation temperature of the compound are controlled, and the stability and yield of a production line are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of organic electroluminescence, in particular to an amine-based compound and an organic electroluminescent device. BACKGROUND

[0002] The core of OLED (Organic Light Emitting Diode) lies in the special material used in its light-emitting layer, i.e. organic electroluminescent compounds. Unlike traditional liquid crystal display (LCD) which needs a backlight source, OLED is a self-luminous display technology based on organic semiconductor materials. Its basic principle is: under the driving of an electric field, electrons injected from the cathode and holes injected from the anode recombine in the light-emitting layer to form high-energy "excitons". When these excitons return from the excited state to the ground state, they release energy in the form of light, realizing electroluminescence. Organic electroluminescent compounds are the core materials that constitute this key light-emitting layer, which directly determine the color (red, green, blue or other), efficiency, brightness and lifetime of the device. These compounds are usually small organic molecules or high molecular polymers with special molecular structures, which need to have excellent charge transport ability, high photoluminescence quantum efficiency, good film-forming property and stable chemical and physical properties. The exploration and research of new and high-performance organic electroluminescent materials have always been the core driving force for the progress of OLED technology, and the continuous optimization of their performance has directly promoted the wide application of today's light, flexible, high-contrast, wide-color OLED display screens in mobile phones, televisions, wearable devices and other fields.

[0003] The compound disclosed in the invention patent with patent number US20160359113A1 The compound disclosed in the invention patent with patent number JP2011006405A and applied to the hole transport layer of an organic electroluminescent device.

[0004] The triarylamine compound formed by 9,9-diphenylfluorene and 9,9-dimethylfluorene and another group is disclosed in the invention patent with patent number CN119118847A, and the compound is deuterated on one of the phenyl groups of 9,9-diphenylfluorene, and the compound is applied to an organic electroluminescent compound and an electron blocking layer of an organic electroluminescent device. By deuterating the phenyl group on 9,9-diphenylfluorene, a certain improvement in performance is achieved. Currently, there is a need to develop better organic electroluminescent materials to adapt to the rapid development of panel material industry. SUMMARY

[0005] The present application provides an amine-based compound, as shown in formula I: R1, R2, R3, R4, R5 are each independently selected from the group consisting of deuterium, substituted or unsubstituted C1-C5 alkyl, substituted or unsubstituted C3-C6 cycloalkyl, substituted or unsubstituted C6-C20 aryl, substituted or unsubstituted C6-C20 heteroaryl, the substituents being selected from the group consisting of deuterium, fluorine, cyano, C1-C5 alkyl, C3-C6 cycloalkyl, C6-C20 aryl, C6-C20 heteroaryl; a, d are each independently selected from the group consisting of integers from 0 to 5, b, c, e are each independently selected from the group consisting of integers from 0 to 4.

[0006] As a preferred embodiment of the present application, the amine-based compound is represented by Formula II or Formula III:

[0007] The definitions of (R1) a , (R2) b , (R3) c , (R4) d , (R5) e in Formula II and Formula III are the same as those in Claim 1.

[0008] As a preferred embodiment of the present application, R1, R2, R3, R4, R5 are each independently deuterium, methyl, deuterated methyl.

[0009] As a preferred embodiment of the present application, R1, R2, R3, R4 are each independently methyl, and R5 is deuterium, methyl, deuterated methyl.

[0010] As a preferred embodiment of the present application, a+b+c+d≤1.

[0011] As a preferred embodiment of the present application, the amine-based compound is one of the following compounds:

[0012]

[0013]

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

[0020] The present application provides an organic electroluminescence device, comprising a first electrode, a second electrode and an organic layer between the first electrode and the second electrode, wherein the organic layer contains any one of the amine-based compounds described above.

[0021] As a preferred embodiment of the present application, the organic layer comprises a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, and at least one of the hole injection layer, the hole transport layer, the electron blocking layer, the light emitting layer, the hole blocking layer, the electron transport layer and the electron injection layer contains any one of the amine-based compounds described above.

[0022] The present application provides an electronic display device containing the organic electroluminescence device described above.

[0023] The present application provides an OLED lighting device containing the organic electroluminescence device described above.

[0024] Compared with the prior art, the present application has the following advantages:

[0025] 1. The amine-based compounds of the present application are deuterated at the active sites of their respective structures, and all have good thermal stability, chemical stability and photoelectric stability.

[0026] 2. The amine-based compounds of the present application effectively control the molecular weight of the compounds while improving the stability of the deuterium, thereby controlling the evaporation temperature and sublimation temperature of the compounds, and further improving the stability and yield of the production line. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 Figure is a structural schematic diagram of the organic electroluminescence device of the present application;

[0028] The numbers in the figure respectively represent: 1-anode, 2-hole injection layer, 3-first hole transport layer, 4-second hole transport layer, 5-light emitting layer, 6-hole blocking layer, 7-electron transport layer, 8-electron injection layer, 9-cathode.

[0029] Figure 2 Figure is the HPLC chart of compound 3 prepared in synthesis example 1 of the present application.

[0030] Figure 3 Figure is the DSC spectrum of compound 3 prepared in synthesis example 1 of the present application, which shows that the Tm value of compound 3 is 289.91℃. Figure 3

[0031] Figure is the TGA spectrum of compound 3 prepared in synthesis example 1 of the present application, which shows that the Td value of compound 3 is 418.20℃. Figure 4 Figure 4 DETAILED DESCRIPTION ​​

[0032] Embodiments of various aspects are further illustrated and described below. It is to be understood that the description herein is not intended to limit the claims to the particular aspects described. Rather, the claims are intended to cover alternatives, modifications and equivalents that can be included within the spirit and scope of the disclosure as defined by the appended claims.

[0033] As used herein, in "deuterated" or "not deuterated," the term "deuterated" means that at least one hydrogen in the group is re-coordinated with deuterium. The term "not deuterated" means that none of the hydrogens in the group are re-coordinated with deuterium.

[0034] "Aromatic," "aryl," or "aromatic group" as used herein means a group containing one or more aromatic rings, where aromatic rings include, but are not limited to, benzene, naphthalene, phenanthrene, fluorene, acenaphthylene, pyridine, pyrimidine, pyrrole, furan, thiophene, and the like. C6-C30 of an aromatic group means that the group contains 6-30 carbon atoms. C1-C10 alkyl-substituted C6-C20 of an aromatic group means that the number of carbon atoms of the substituent is C1-C10, and the number of carbon atoms of the aromatic group not including the substituent is C6-C20. Aromatic groups can be classified as monocyclic aryl groups and polycyclic aryl groups. Specific aromatic groups in the present application include, but are not limited to, phenyl, biphenyl, terphenyl, anthracenyl, naphthyl, phenanthryl, fluorenyl, dibenzofuranyl, dibenzothiophenyl, 9,9-spirobifluorenyl, 9,9-dimethylfluorenyl, or 9,9-diphenylfluorenyl, and the like. Aromatic groups can be substituted and unsubstituted.

[0035] "Deuterated methyl" as used herein means any one of monodeuterated methyl, bisdeuterated methyl, trideuterated methyl.

[0036] "Cycloalkyl" as used herein means a monocyclic or fused ring ("fused" rings mean that each ring in the system shares a pair of adjacent carbon atoms with another ring in the system) group all of which are carbon, wherein one or more rings are saturated aliphatic rings, which typically have 3-20 carbon atoms, preferably 3-12 carbon atoms, more preferably 3-10 carbon atoms. Cycloalkyl groups can be classified as monocycloalkyl groups having only one ring and fused cycloalkyl groups having multiple rings. Examples of monocycloalkyl groups include, but are not limited to, cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane. Cycloalkyl groups can be substituted and unsubstituted.

[0037] "a, d are each independently an integer selected from 0-5" as used herein means that a, d can be individually 0, 1, 2, 3, 4, 5; "b, c, e are each independently an integer selected from 0-4" as used herein means that b, c, e can be individually 0, 1, 2, 3, 4.

[0038] "Heteroaryl" as used herein refers to a heteroaryl group in which one or more C in the structure of "aryl" is replaced by one or more heteroatoms (e.g., N, O, or S).

[0039] Unless otherwise indicated, conventional conditions or manufacturer's recommendations were used in the examples. Unless otherwise indicated, the reagents or instruments used were conventional products available commercially.

[0040] Synthesis Example 1:

[0041] Compound 3

[0042]

[0043] S1:

[0044] Procedure: 2L three-necked flask was charged with 3-SM1 (100.5g, 0.62mol, 1eq) and super dry THF (700ml), cooled to below -65℃, dropwise added n-butyllithium (260ml, 0.65mol, 1.05eq), after dropwise addition, stirred for 1h, dropwise added 3-SM2 (109g, 0.589mol, 0.95eq) in super dry THF (300ml) solution, after dropwise addition, stirred at room temperature overnight.

[0045] Work-up: stop the reaction, added 800ml saturated aqueous ammonium chloride solution to quench, stirred and separated into water and organic phases, the organic phase was dried over anhydrous sodium sulfate, the filtrate was concentrated to dryness under reduced pressure, and used directly in the next step without purification.

[0046] S2:

[0047] Procedure: 2L three-necked flask was charged with 3-ZJ1 (0.62mol, calculated theoretically), I2 (252g, 0.992mol, 1.6eq), potassium carbonate (257.2g, 0.806mol, 3eq) and tert-butyl alcohol (500ml), under N2protection, heated to 90℃ and stirred to react, HPLC monitoring 3-ZJ1≤0.5%.

[0048] Work-up: stop the reaction, added 800ml 50% aqueous sodium thiosulfate solution to quench, stirred to precipitate solids, suction filtered, the filter cake was washed with water, and the filter cake was dried at 85℃ to obtain 124g of light yellow solid (3-ZJ2), with a two-step yield of 78.1%.

[0049] S3:

[0050] Procedure: 2L three neck flask was charged with 3-SM3 (114g, 0.489mol, 1 eq) and super dry THF (500ml), cooled to below -65°C, dropwise added n-butyllithium (205ml, 0.513mol, 1.05eq), after dropwise addition, stirred for 1h, dropwise added 3-ZJ2 (124g, 0.465mol, 0.95eq) in super dry THF (300ml) solution, after dropwise addition, stirred at room temperature overnight.

[0051] Work-up: stop the reaction, added 800ml saturated aqueous ammonium chloride solution to quench, stirred and separated, the aqueous phase was extracted with DCM, the combined organic phase was dried over anhydrous sodium sulfate, the filtrate was concentrated to dryness under reduced pressure, and was used directly in the next step without purification.

[0052] S4:

[0053] Procedure: 2L single neck flask was charged with 3-ZJ3 (calculated according to the theoretical amount, 0.465mol, 1 eq) and DCM (1000ml), cooled to below 0°C, added methane sulfonic acid (269g, 2.79mol, 6eq), after addition, moved to room temperature and stirred for 1-2h, HPLC monitored 3-ZJ3≤0.5%.

[0054] Work-up: stop the reaction, cooled, slowly added water to quench the reaction, stirred and separated, the organic phase was washed with water for 2 times, added 200g 100-200 mesh silica gel to make sand, 600g 100-200 mesh silica gel was packed into a column, column chromatography was performed, PE / DCM=1000 / 1-100 / 1-50 / 1, the product point was collected, concentrated to dryness under reduced pressure, to obtain 117.2g white solid, the two-step yield was 62.6%.

[0055] S5:

[0056] Procedure: 1L three neck flask was charged with 3-ZJ4 (30g, 74.6mmol, 1 eq), 3-SM4 (24g, 74.6mol, 1 eq), sodium tert-butoxide (8.6g, 89.52mmol, 1.2eq), tri-tert-butyl phosphine (6ml, 2.984mmol, 0.04eq) and toluene (300ml), under N2protection, added tris-dibenzylideneacetone palladium (1.39g, 1.492mmol, 0.02eq), after addition, heated to 100°C and stirred, HPLC monitored ZJ4≤1%.

[0057] Post-treatment: stop the reaction, add 400 ml water, stir, separate the liquid, extract the water phase with DCM, combine the organic phase, extract with silica gel, filter the filtrate under reduced pressure, add 200 ml toluene, 400 ml ethanol, stir at 85℃ for 2-3 h, solid precipitates, cool to room temperature, filter, filter cake is recrystallized with toluene+ethanol twice, filter cake is dried at 85℃ with air blowing, to obtain 34.5 g of white solid 3, HPLC purity 99.9675%, yield 71.9%.

[0058] The compounds described in Table 1: 1, 8, 9, 15, 21, 26, 32, 39, 50, 51, 57, 69, 75, 86, 87, 99, 105, 110, 115, 121, 124 were obtained in a similar manner: Forming Synthesis Examples 2-22.

[0059] Table 1

[0060]

[0061]

[0062]

[0063]

[0064] The synthetic identification results of the compounds prepared in Synthesis Examples 1-19 are shown in Table 2 below:

[0065] Table 2

[0066]

[0067] Material performance test.

[0068] The compound 3 prepared in Synthesis Example 1 of the present application was tested for thermal weight loss temperature Td and melting point Tm, respectively. The thermal weight loss temperature Td is the temperature at which the mass loss is 5% under a nitrogen atmosphere, and was measured on a TGA N-1000 thermal gravimetric analyzer with a nitrogen flow rate of 10 mL / min. The melting point Tm was measured by differential scanning calorimetry (DSC, Shinco DSC N-650) at a heating rate of 10℃ / min. The test results are shown in Table 3 below. Figure 3 、 Figure 4 The melting point Tm of compound 3 is 289.91℃, and the thermal weight loss temperature Td of compound 3 is 418.20℃. From the above test results, it can be seen that the compound prepared in Synthesis Example of the present application has a high Td value and a suitable melting point, and therefore the compound of the present application has excellent thermal stability, meeting the evaporation and use requirements as an organic electroluminescent compound.

[0069] Device performance test.

[0070] Application Example 1

[0071] ITO is used as the anode substrate material of the reflective layer, and the surface is treated with water, acetone, N2 plasma, and the like in sequence;

[0072] On the ITO anode substrate, 10 nm of HT-1 doped with NDP-9 at a mass ratio of 5% is deposited to form a hole injection layer (HIL);

[0073] On the hole injection layer (HIL), 100 nm of HT-1 is evaporated to form a first hole transport layer (HTL);

[0074] On the first hole transport layer (HTL), the compound 3 prepared in Synthesis Example 1 of the present application is vacuum evaporated to form a second hole transport layer (GPL) with a thickness of 10 nm;

[0075] Compound GH-1 and GH-2 are co-evaporated as light-emitting host materials at a mass ratio of 5:5, and GD-1 is evaporated as a dopant material (the amount of GD-1 is 8% of the total mass of GH-1 and GH-2) on the second hole transport layer (GPL) to form a light-emitting layer with a thickness of 20 nm;

[0076] HB-1 is evaporated on the light-emitting layer to obtain a hole blocking layer (HBL) with a thickness of 20 nm;

[0077] ET-1 and LiQ are co-evaporated on the hole blocking layer (HBL) at a mass ratio of 5:5 to obtain an electron transport layer (ETL) with a thickness of 30 nm;

[0078] Magnesium (Mg) and silver (Ag) are mixed and evaporated on the electron transport layer (ETL) at a mass ratio of 9:1 to form an electron injection layer (EIL) with a thickness of 50 nm;

[0079] Thereafter, silver (Ag) is evaporated on the electron injection layer to form a cathode with a thickness of 100 nm, and 50 nm of DNTPD is deposited on the cathode sealing layer. In addition, the cathode surface is sealed with a UV-hardening adhesive and a seal cap containing a moisture absorbent to protect the organic electroluminescent device from the influence of oxygen or moisture in the atmosphere. Thus, the organic electroluminescent device is prepared.

[0080]

[0081]

[0082] Application Example 2-22

[0083] The compound 1, 8, 9, 15, 21, 26, 32, 39, 50, 51, 57, 69, 75, 86, 87, 99, 105, 110, 115, 121, 124 prepared by synthetic example 2-22 of the present application was used as a hole blocking layer material, and the rest was the same as application example 1, thereby preparing an organic electroluminescent device of application examples 2-22.

[0084] Comparative examples 1-5

[0085] The compound D1-17, D1-18, D1-19, D1-20, D1-23 in CN 119118847A was used as a hole blocking layer material, and the rest was the same as application example 1, thereby preparing comparative examples 1-5.

[0086]

[0087] Comparative examples 6-9

[0088] The compound D2-100, D2-101, D2-102, D2-118 in JP2011006405A was used as a hole blocking layer material, and the rest was the same as application example 1, thereby preparing comparative examples 6-9.

[0089]

[0090] Comparative example 10

[0091] The compound D3-36 in US20160359113A1 was used as a hole blocking layer material, and the rest was the same as application example 1, thereby preparing comparative example 10.

[0092]

[0093] The organic electroluminescent devices prepared by application examples 1-22 and comparative examples 1-10 were tested for device performance, and the performance test was determined under the condition of a current density of 10 mA / cm 2 , and the test results are shown in Table 3.

[0094] Table 3

[0095]

[0096]

[0097] From the above Table 3, it can be seen that the compound of the present application applied to the organic electroluminescent device, under the same current density, the luminous efficiency is improved, the starting voltage of the device is reduced, and the performance of the device is effectively improved.

[0098] The organic electroluminescent devices prepared in the application examples 1-10 and the control examples 1-10 were subjected to lifetime test, respectively, to obtain the T97% data (time for the luminous intensity to drop to 97%) of the luminescent lifetime, and the test equipment was TEO luminescent device lifetime test system. The test results are shown in Table 4.

[0099] Table 4

[0100]

[0101]

[0102] As can be seen from Table 4, the organic electroluminescent devices prepared by using the amine-based compounds of the application have improved device lifetime under the same current density. In combination with Table 3, the organic electroluminescent devices prepared by using the amine-based compounds of the application have improved startup voltage, luminous efficiency and lifetime, and have broad application prospects.

[0103] The above detailed description is only a specific description of the feasible embodiments of the application, and is not intended to limit the protection scope of the application. Any equivalent embodiments or changes made without departing from the spirit of the application shall fall within the protection scope of the application.

[0104] In addition, it should be understood that although the present specification is described in terms of embodiments, not every embodiment contains only one independent technical solution, and the description manner of the specification is only for the sake of clarity, and the skilled person should consider the specification as a whole, and the technical solutions in each embodiment can be properly combined to form other embodiments that can be understood by the skilled person.

Claims

1. An amino compound, characterized in that, As shown in Equation I: In Formula I, R1, R2, R3, R4, and R5 are each independently selected from deuterium, substituted or unsubstituted C1-C5 alkyl, substituted or unsubstituted C3-C6 cycloalkyl, substituted or unsubstituted C6-C20 aryl, and substituted or unsubstituted C6-C20 heteroaryl. The substituents are selected from deuterium, fluorine, cyano, C1-C5 alkyl, C3-C6 cycloalkyl, C6-C20 aryl, and C6-C20 heteroaryl. a and d are each independently selected from integers from 0 to 5, and b, c, and e are each independently selected from integers from 0 to 4.

2. An amino compound according to claim 1, characterized in that, As shown in Equation II or Equation III: Regarding (R1) in Equations II and III a (R2) b (R3) c (R4) d (R5) e The definition is the same as in claim 1.

3. An amino compound according to claim 1, characterized in that, R1, R2, R3, R4, and R5 are independently deuterium, methyl, and deuterated methyl, respectively.

4. An amino compound according to claim 1, characterized in that, R1, R2, R3, and R4 are methyl groups, and R5 is deuterium, methyl, or deuterated methyl.

5. An amino compound according to claim 1, characterized in that, a+b+c+d≤1.

6. An amino compound according to claim 1, characterized in that, The amino compound is one of the following structural formulas:

7. An organic electroluminescent device, characterized in that, It includes a first electrode, a second electrode, and an organic layer between the first electrode and the second electrode, wherein the organic layer contains an amine compound as described in any one of claims 1-6.

8. An organic electroluminescent device according to claim 7, characterized in that, The organic layer comprises a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer, wherein at least one of the hole injection layer, hole transport layer, electron blocking layer, light-emitting layer, hole blocking layer, electron transport layer, and electron injection layer contains an amino compound as described in any one of claims 1-6.

9. An electronic display device, characterized in that, It contains the organic electroluminescent device as described in claim 7.

10. An OLED lighting device, characterized in that, It contains the organic electroluminescent device as described in claim 7.

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