CN107098818A - Aromatic compound and organic light emitting diode comprising same - Google Patents

Abstract

An aromatic compound represented by Chemical Formula 1 and an organic light-emitting diode comprising the same. In Chemical Formula 1, A, Ar2, R1, R2 and m are the same as those described in the embodiment. The aromatic compound of the present invention has the characteristics of blue light emission, high quantum efficiency and excellent thermal stability. In addition, the aromatic compound of the present invention can be applied to the light-emitting layer or hole transport layer of the organic light-emitting diode to improve the external quantum efficiency, maximum brightness, current efficiency, power efficiency and life of the organic light-emitting diode.

Description

Aromatic compound and organic light emitting diode containing same

technical field

The present invention relates to a compound and an organic light emitting diode comprising it, in particular to an aromatic compound and an organic light emitting diode comprising it.

Background technique

Organic light-emitting diode (OLED) flat-panel displays have advantages such as wider viewing angles, faster response times, and thinner volumes compared to liquid crystal displays, and are currently being used in large-area, high-brightness, and full-color displays.

In order to develop a full-color flat-panel display, developing stable and high-efficiency light-emitting materials (red, green, blue) is the main goal of current OLED research. However, compared with red and green light-emitting materials, the development of blue light-emitting materials in terms of luminous efficiency and luminous lifetime is relatively slow. goal to strive for.

Contents of the invention

The present invention provides an aromatic compound capable of realizing an organic light emitting diode with high luminous efficiency and long life.

The present invention provides an aromatic compound represented by the following chemical formula 1:

[chemical formula 1]

In Chemical Formula 1, R ₁ and R ₂ are each independently hydrogen, halogen, C ₁ -C ₆ alkyl or aryl, m is an integer of 0 or 1, and A is substituted or unsubstituted carbazolyl Ar ₁ or an organic amino group, and _Ar is substituted or unsubstituted pyrenyl, substituted or unsubstituted sulfonyl, substituted or unsubstituted triazinyl, or substituted or unsubstituted

In one embodiment of the present invention, the above-mentioned aromatic compound is represented by the following chemical formula 2:

[chemical formula 2]

In Chemical Formula 2, Ar ₃ is selected from the following structural formulas,

The remaining substituents are the same as defined in Chemical Formula 1.

In one embodiment of the present invention, the above-mentioned aromatic compound is represented by the following chemical formula 3:

[chemical formula 3]

In Chemical Formula 3, Ar ₄ is selected from the following structural formulas,

The remaining substituents are the same as defined in Chemical Formula 1.

In one embodiment of the present invention, the above-mentioned Ar ₂ is selected from the following structural formulas,

The invention provides an organic light-emitting diode, which includes a cathode, an anode and a light-emitting layer. The light-emitting layer is arranged between the cathode and the anode, wherein the light-emitting layer contains the above-mentioned aromatic compound

In an embodiment of the present invention, the aforementioned organic light emitting diodes are, for example, blue light emitting diodes.

In an embodiment of the present invention, the above-mentioned light-emitting layer includes a host light-emitting material and a guest light-emitting material.

In an embodiment of the present invention, the above-mentioned host light-emitting material includes the aromatic compound.

In an embodiment of the present invention, the above-mentioned guest light-emitting material includes the aromatic compound.

In one embodiment of the present invention, the above-mentioned host luminescent material is, for example, 1-(2,5-dimethyl-4-(1-pyrenyl)phenyl)pyrene (1-(2,5-dimethyl-4 -(1-pyrenyl)phenyl)pyrene; DMPPP), 4,4'-N,N'-dicarbazole-biphenyl (4,4'-N,N'-dicarbazole-biphenyl; CBP) or 2-( 3-(pyren-1-yl)phenyl)triphenylene (2-(3-(pyren-1-yl)phenyl)triphenylene; m-PPT).

In an embodiment of the present invention, the above-mentioned organic light emitting diode further includes at least one auxiliary layer, and the auxiliary layer is selected from a hole injection layer, a hole transport layer, a hole blocking layer, an electron injection layer, an electron transport layer and A group of electron blocking layers.

In an embodiment of the present invention, the above-mentioned at least one auxiliary layer includes the above-mentioned aromatic compound.

Based on the above, the aromatic compound of the present invention has the characteristics of blue light emission, high quantum efficiency, and excellent thermal stability. In addition, the aromatic compound of the present invention can be applied in the light-emitting layer or the hole transport layer of the organic light-emitting diode, so as to improve the external quantum efficiency, maximum brightness, current efficiency, power efficiency and lifetime of the organic light-emitting diode.

In order to make the above-mentioned features and advantages of the present invention more comprehensible, the following specific embodiments are described in detail together with the accompanying drawings.

Description of drawings

1 is a schematic cross-sectional view of an organic light emitting diode according to an embodiment of the present invention;

2 is a schematic cross-sectional view of an organic light emitting diode according to another embodiment of the present invention;

Figure 3A and Figure 3B are the transient light-excited fluorescence curves of the toluene solution containing the compound CZSSO under air and nitrogen respectively;

Figure 4A and Figure 4B are the transient light-excited fluorescence curves of the toluene solution containing the compound TCZSSO under the conditions of air and nitrogen respectively;

Figure 5A and Figure 5B are the transient light-excited fluorescence curves of the toluene solution containing the compound OCZSSO under air and nitrogen respectively;

Figure 6A and Figure 6B are the transient light-excited fluorescence curves of the toluene solution containing the compound CZSDCN under air and nitrogen respectively;

Figure 7A and Figure 7B are the transient light-excited fluorescence curves of the toluene solution containing the compound CZSDPT under air and nitrogen respectively;

Fig. 8 is the transient electric excitation fluorescence curve of the organic light-emitting diode of experimental example 1 to experimental example 4;

Fig. 9 is the transient electroluminescence curves of the organic light-emitting diodes of Experimental Example 5 to Experimental Example 7 and Comparative Example;

Fig. 10 is the transient electric excitation fluorescence curve of the organic light-emitting diodes of Experimental Example 8 to Experimental Example 10;

Fig. 11 is the transient electric excitation fluorescence curve of the organic light-emitting diode of experimental example 18;

12 is the luminance-external quantum efficiency curves of the organic light emitting diodes of Experimental Example 11 to Experimental Example 15.

Reference signs:

10, 20: Organic light-emitting diodes

102: anode

103: Hole transport layer

104: Cathode

105: Electron transport layer

106: Luminous layer

detailed description

Hereinafter, embodiments of the present invention are described in detail. However, these examples are exemplary, and the present invention is not limited thereto.

An aromatic compound according to an embodiment of the present invention is represented by the following chemical formula 1:

[chemical formula 1]

In Chemical Formula 1, R ₁ and R ₂ are each independently hydrogen, halogen, C ₁ -C ₆ alkyl or aryl. m is an integer of 0 or 1. A is a substituted or unsubstituted carbazolyl Ar ₁ or is an organic amino group. Ar ₂ is substituted or unsubstituted pyrenyl, substituted or unsubstituted sulfonyl, substituted or unsubstituted triazinyl or substituted or unsubstituted

In one embodiment of the present invention, the aromatic compound is represented by the following chemical formula 2:

[chemical formula 2]

In chemical formula 2, R ₁ , R ₂ and Ar ₂ are the same as those defined in chemical formula 1, and Ar ₃ is, for example, selected from the following structural formulas:

In another embodiment of the present invention, the aromatic compound is represented by the following chemical formula 2:

[chemical formula 3]

In chemical formula 3, R ₁ , R ₂ and Ar ₂ are the same as those defined in chemical formula 1, and Ar ₄ is selected from the following structural formulas:

In this specification, if not otherwise defined, the term "substituted" means substituted by the following groups: halogen, aryl, hydroxyl, alkenyl, C ₁ -C ₂₀ alkyl, alkynyl, cyano, Trifluoromethyl, alkylamino, amino, C ₁ -C ₂₀ alkoxy, heteroaryl, aryl with halogen substituent, aralkyl with halogen substituent, aryl with haloalkyl substituent , aralkyl with haloalkyl substituent, C ₁ -C ₂₀ alkyl with aryl substituent, cycloalkyl, amine with C ₁ -C ₂₀ alkyl substituent, amine with haloalkyl substituent A group, an amino group with an aryl substituent, an amino group with a heteroaryl substituent, a phosphorus oxy group with an aryl substitution, a phosphorus oxy group with a C ₁ -C ₂₀ alkyl substitution, a haloalkyl substituent Phosphoryloxy, phosphoryloxy with a halogen substituent, phosphorusoxy with a heteroaryl substituent, nitro, carbonyl, arylcarbonyl, heteroarylcarbonyl or _C1 - _C20 alkyl with a halogen substituent .

In this specification, the term "aryl" refers to a substituent including a ring having a p-orbital forming a conjugate, and it may be a monocyclic, polycyclic or fused ring polycyclic functional group.

Specifically, examples of the aryl group include phenyl, phenylene, naphthyl, naphthylene, pyrenyl, anthryl, and phenanthryl, But not limited to this.

In the present specification, the term "heteroaryl" refers to an aryl group including 1 to 3 heteroatoms selected from N, O, S, P and Si and the remaining carbons in a functional group. Heteroaryl groups can be fused rings, wherein each ring can include 1 to 3 heteroatoms.

Specifically, examples of heteroaryl include furyl, furylene, fluorenyl, pyrrolyl, thienyl, oxazolyl, imidazolyl (imidazolyl), thiazolyl, pyridyl, pyrimidinyl, quinazolinyl, quinolyl, isoquinolyl, and indolyl ), but not limited to this.

Hereinafter, an organic light emitting diode according to an embodiment of the present invention will be described with reference to drawings.

FIG. 1 is a schematic cross-sectional view of an organic light emitting diode according to an embodiment of the present invention.

Referring to FIG. 1 , the organic light emitting diode 10 of this embodiment includes an anode 102 , a cathode 104 and a light emitting layer 106 . The light emitting layer 106 is disposed between the anode 102 and the cathode 104 . The anode 102 can be made of a conductor with a high work function to facilitate hole injection into the light emitting layer 106 . The material of the anode 102 is, for example, metal, metal oxide, conductive polymer or a combination thereof. Specifically, metals such as nickel, platinum, vanadium, chromium, copper, zinc, gold or alloys thereof; metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO) or indium zinc oxide (IZO); metal Combinations with oxides are, for example, combinations of ZnO and Al or combinations of SnO ₂ and Sb; conducting polymers are, for example, poly(3-methylthiophene) (poly(3-methylthiophene)), poly(3,4-(extended Ethyl-1,2-dioxy)thiophene (poly(3,4-(ethylene-1,2-dioxy)thiophene, PEDT), polypyrrole (polypyrrole) or polyaniline (polyaniline), but the present invention is not limited to this.

Cathode 104 may be made of a conductor with a low work function to aid injection of electrons into light emitting layer 106 . The material of the cathode 104 is, for example, metal or a material with a multilayer structure. Specifically, metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium (gadolinium), aluminum, silver, tin, lead, cesium, barium or alloys thereof; LiF/Al, LiO ₂ /Al, LiF/Ca, LiF/Al or BaF ₂ /Ca, but the present invention is not limited thereto.

In this embodiment, the light-emitting layer 106 includes the aromatic compound of the above-mentioned embodiments. Specifically, the light-emitting layer 106 includes one aromatic compound of the foregoing embodiments, at least two aromatic compounds of the foregoing embodiments, or a mixture of at least one of the aromatic compounds of the foregoing embodiments and other compounds.

The light-emitting layer 106 generally includes a host light-emitting material and a guest light-emitting material. The aromatic compound in the above embodiments can be used as a guest luminescent material and mixed with a host luminescent material, or can be used as a host luminescent material and mixed with a guest luminescent material.

Other host luminescent materials are, for example, condensation aromatic cycle derivatives, heterocycle-containing compounds or the like. Condensed aromatic ring derivatives are, for example, anthracene derivatives, pyrene derivatives, naphthalene derivatives, pentacene derivatives, phenanthrene derivatives, fluoranthene derivatives, and fluoranthene derivatives. ) compound or its analog. Compounds containing heterocycles are, for example, carbazole derivatives, dibenzofuran derivatives, ladder-type furan compounds, pyrimidine derivatives or the like. Specifically, the host luminescent material is, for example, 1-(2,5-dimethyl-4-(1-pyrene)phenyl)pyrene (1-(2,5-dimethyl-4-(1-pyrenyl)phenyl) pyrene; DMPPP), 4,4'-N,N'-dicarbazole-biphenyl (4,4'-N,N'-dicarbazole-biphenyl; CBP) or 2-(3-(pyrene-1-yl )phenyl)triphenylene (2-(3-(pyren-1-yl)phenyl)triphenylene; m-PPT), but the present invention is not limited thereto.

The guest light-emitting materials other than the aromatic compounds in the above embodiments are, for example, arylamine derivatives, styrylamine compounds, boron complexes, fluoranthene compounds, metal complexes or the like. Specifically, arylamine derivatives are, for example, fused aromatic ring derivatives substituted by arylamine groups, examples of which include pyrene, anthracene, chrysene, and periflanthene with arylamine groups; Specific examples of vinylamine compounds include styrylamine, styryldiamine, styryltriamine, and styryltetramine. Examples of metal complexes include, but not limited to, iridium complexes and platinum complexes.

In one embodiment, the organic light emitting diode 10 further includes at least one auxiliary layer, the auxiliary layer is selected from a hole injection layer, a hole transport layer, a hole blocking layer, an electron injection layer, an electron transport layer and an electron blocking layer. group.

In one embodiment, at least one auxiliary layer comprises the aromatic compound of the above embodiment.

FIG. 2 is a schematic cross-sectional view of an organic light emitting diode according to another embodiment of the present invention. In FIG. 2 , the same components as those in FIG. 1 will be denoted by the same reference numerals, and descriptions of the same technical content will be omitted. The organic light emitting diode 20 includes an anode 102 , a hole transport layer 103 , a light emitting layer 106 , an electron transport layer 105 and a cathode 104 .

In this embodiment, the light-emitting layer 106 includes the aromatic compound of the above-mentioned embodiments. In another embodiment, in addition to the light emitting layer 106 comprising the aromatic compound of the above embodiment, at least one of the hole transport layer 103 and the electron transport layer 105 also includes the aromatic compound of the above embodiment.

Hereinafter, the above-described embodiments are explained in more detail with reference to Examples. However, these examples are not to be construed as limiting the scope of the invention in any sense.

Synthesis of Organic Compounds

[Intermediate Synthesis]

Synthesis Example 1: Synthesis of Intermediate I-1

[Reaction scheme 1]

4-(diphenylamino)benzaldehyde (4-(diphenylamino)benzaldehyde) (2.73g, 10.0mmol) and 4-bromobenzyl phosphate diethyl (diethyl(4-bromobenzyl)phosphonate) (3.53g, 11.5mmol) was placed in a double-necked flask, vacuumized and fed with nitrogen, and then 20mL of anhydrous tetrahydrofuran (THF) was added; under ice-cooling, potassium tert-butoxide (t-BuOK) dissolved in THF (30mL) ) (3.36g, 30mmole) was slowly added and mixed, and reacted at 0°C for 15 minutes. The solvent was removed by concentration under reduced pressure, and then purified by column chromatography (n-hexane:dichloromethane=9:1) to obtain a yellow intermediate product I-1 ((E)-4-(4-bromostyryl)- N,N-diphenylaniline) (3.71 g, 87% yield).

¹ H NMR (400MHz, CDCl3, δ): 7.45(d, J=8.4Hz, 2H), 7.36(d, J=8.8Hz, 2H), 7.34(d, J=8.8Hz, 2H), 7.28-7.24 (m,4H),7.11(d,J=7.6Hz,4H),7.05-7.01(m,5H),6.90(d,J=16Hz,1H).

¹³ C NMR (100MHz, CDCl ₃ , δ): 147.53, 147.38, 136.50, 131.65, 130.89, 129.68, 129.26, 127.69, 127.37, 125.55, 124.52, 123.30, 123.09, 120.80.

HRMS (m/z): [M] ⁺ calcd for C ₂₆ H ₂₀ BrN, 425.0779; found, 425.0772.

Synthesis example 2: the synthesis of intermediate product 1-2

[Reaction scheme 2]

4-(bis(4-fluorophenyl)amine)benzaldehyde (4-(bis(4-fluorophenyl)amino)benzaldehyde) (4.64g, 15mmol) and 4-bromobenzyl phosphate diethyl (diethyl(4 -bromobenzyl)phosphonate) (5.07g, 16.5mmol) was placed in a two-necked flask, vacuumized and nitrogen was introduced, and 20mL of anhydrous tetrahydrofuran (THF) was added; Potassium tert-butoxide (t-BuOK) (5.0 g, 45 mmol) was slowly added and mixed, and reacted at 0° C. for 15 minutes. The solvent was removed by concentration under reduced pressure, and then purified by column chromatography (n-hexane:dichloromethane=9:1) to obtain a yellow intermediate product I-2 ((E)-4-(4-bromostyryl)- N,N-bis(4-fluorophenyl)aniline) (6.17 g, 89% yield).

¹ H NMR (400MHz, CDCl ₃ , δ): 7.44(d, J=8.4Hz, 2H), 7.33(d, J=8.8Hz, 2H), 7.32(d, J=8.8Hz, 2H), 7.06- 6.92(m,11H),6.88(d,J=16Hz,1H).

¹³ C NMR (100MHz, CDCl ₃ , δ): 158.00ppm (d, ¹³ C- ¹⁹ F coupling J＝242Hz, C), 147.62 (C), 143.42 (d, ¹³ C- ¹⁹ F coupling J＝3Hz, C ), 136.47(C), 131.69(CH), 130.69(C), 128.70(CH), 127.71(CH), 127.47(CH), 126.23(d, ¹³ C- ¹⁹ F coupling J＝7.6Hz, CH), 125.62(CH), 122.10(CH), 120.86(C), 116.15(d, ¹³ C- ¹⁹ F coupling J＝22.8Hz, CH)

HRMS (m/z): [M] ⁺ calcd. for C ₂₆ H ₁₈ BrF ₂ N, 461.0591; found, 461.0594.

Synthesis example 3: the synthesis of intermediate product 1-3

[Reaction scheme 3]

4-(1-naphthalenyl(phenyl)amine)carbaldehyde (4-(naphthalen-1-yl(phenyl)amino)benzaldehyde) (2.87g, 8.9mmol l) and 4-bromobenzyl diethyl phosphate (diethyl(4-bromobenzyl)phosphonate)(3.0g, 9.76mmol) was placed in a two-necked flask, vacuumized and fed with nitrogen, and then 20mL of anhydrous tetrahydrofuran (THF) was added; Potassium tert-butoxide (t-BuOK) (2.24 g, 20 mmol) in THF (30 mL) was slowly added and mixed, and reacted at 0° C. for 15 minutes. The solvent was removed by concentration under reduced pressure, and then purified by column chromatography (n-hexane:dichloromethane=9:1) to obtain a yellow intermediate product I-3 ((E)-N-(4-(4- bromostyryl)phenyl)-N-phenylnaphthalen-1-amine) (2.67 g, 63% yield).

¹ H NMR (400MHz, CDCl ₃ , δ): 7.91-7.86(m, 2H), 7.77(d, J=8.0Hz, 1H), 7.48-7.29(m, 10H), 7.22-6.94(m, 8H) ,6.85(d,J=16Hz,1H).

¹³ C NMR(100MHz,CDCl ₃ ,δ):148.22,147.89,143.11,136.63,135.24,131.67,131.11,129.95,129.17,128.93,128.41,127.66,127.37,127.24,126.66,126.48,126.34,126.18,125.13, 124.11, 122.48, 122.26, 121.11, 120.69.

HRMS (m/z): [M] ⁺ calcd. for C ₃₀ H ₂₂ BrN, 475.0936; found, 475.0937.

Synthesis Example 4: Synthesis of Intermediate I-4

[Reaction scheme 4]

9-phenyl-9H-carbazole-3-carbaldehyde (9-phenyl-9H-carbazole-3-carbaldehyde) (3.52g, 13mmol) and 4-bromobenzyl phosphate )phosphonate) (4.42g, 14.4mmol) was placed in a double-necked flask, vacuumized and nitrogen was introduced, and 20mL of anhydrous tetrahydrofuran (THF) was added; Potassium butoxide (t-BuOK) (3.36g, 30mmol) was slowly added and mixed, and reacted at 0°C for 15 minutes. The solvent was removed by concentration under reduced pressure, and then purified by column chromatography (n-hexane:dichloromethane=5:1) to obtain the white intermediate product I-4 ((E)-3-(4-bromostyryl)- 9-phenyl-9H-carbazole) (4.52 g, 82% yield).

¹ H NMR (400MHz, CDCl ₃ , δ): 8.26(s, 1H), 8.15(d, J=7.6Hz, 1H), 7.60-7.35(m, 13H), 7.31-7.27(m, 2H), 7.07 (d,J=16.4Hz,1H).

¹³ C NMR(100MHz,CDCl ₃ ,δ):141.26,140.64,137.41,136.76,131.68,130.11,129.88,129.18,127.68,127.53,126.96,126.18,125.04,124.68,123.72,123.24,120.61,120.33,120.17, 118.64, 110.00, 109.95.

HRMS m/z: [M] ⁺ calcd for C ₂₆ H ₁₈ BrN, 423.0623; found, 423.0621.

Synthesis Example 5: Synthesis of Intermediate Product I-5

[Reaction scheme 5]

Potassium tert-butoxide (t-BuOK) (0.22 g, 2 mmol) was placed in a two-necked flask, and after vacuuming and nitrogen gas flow, 3 mL of anhydrous tetrahydrofuran (THF) was added. Diethyl (4- bromobenzyl)phosphonate) (0.34g, 1.1mmol)

Place in a single-necked bottle, and add 3 mL of anhydrous tetrahydrofuran under nitrogen atmosphere. The solution in the single-necked bottle was slowly added into the double-necked bottle under ice bath and mixed, and reacted at 0° C. for 1 day. The reaction solution was poured into water to precipitate a yellow solid. The precipitated yellow solid is suction-filtered and washed repeatedly with methanol to obtain the intermediate product I-5 ((E)-9-(4-(4-bromostyryl)phenyl)-9H-carbazole) as a light yellow powder (0.39 g, 93% yield).

¹ H NMR (400MHz, CDCl ₃ ): δ8.13(d, J=7.6Hz, 2H), 7.71(d, J=8.4Hz, 2H), 7.55(d, J=8.4Hz, 2H), 7.50( d,J=8.8Hz,2H),7.44-7.38(m,6H),7.30-7.26(m,2H),7.19(d,J=16Hz,1H),7.11(d,J=16Hz,1H)

¹³ C NMR (100MHz, CDCl ₃ ): δ140.69, 137.09, 136.05, 13.01, 131.86, 128.34, 128.21, 128.04, 127.84, 127.19, 125.95, 123.42, 121.60, 120.32, 120.077, 109

Synthesis Example 6: Synthesis of Intermediate I-6

[Reaction scheme 6]

The intermediate product I-5 (0.42g, 1mmol) and bis-linked pinacol borate (4,4,4',4',5,5,5',5'-octamethyl-2,2'-bi (1,3,2-dioxaborolane)) (0.31 g, 1.2 mmol) was placed in a high pressure tube. Potassium acetate (0.29 g, 2.93 mmol) and bistriphenylphosphine palladium dichloride (Pd(PPh ₃ ) ₂ Cl ₂ ) (0.04 g, 0.05 mmol) were added into a high pressure tube. Add 4 mL of anhydrous tetrahydrofuran under nitrogen atmosphere, and mix the above compounds. The mixture was heated and reacted at 80° C. for 1 day, and the reaction solution was filtered through Celite and silica gel. After the solvent was removed by rotary concentration, the column chromatography (ethyl acetate:n-hexane=1:5) was used for purification to obtain a white intermediate product I-6 ((E)-9-(4-(4 -(3,3,4,4-tetramethylborolan-1-yl)styryl)phenyl)-9H-carbazole) (0.20 g, 43% yield).

¹ H NMR (400MHz, CDCl ₃ ): δ8.14-8.12(m, 2H), 7.82(d, J=8.4Hz, 2H), 7.73(d, J=8.4Hz, 2H), 7.55(d, J ＝7.6Hz, 4H), 7.44-7.38(m, 4H), 7.30-7.25(m, 3H), 7.19(d, J＝16.4Hz, 1H), 1.35(s, 12H)

¹³ C NMR (100MHz, CDCl ₃ ): δ140.72, 139.73, 136.98, 136.31, 135.21, 134.71, 129.45, 128.56, 127.89, 127.17, 125.95, 125.89, 123.40, 120.870, 1139.881, 208, 1

Synthesis Example 7: Synthesis of Intermediate I-7

[Reaction scheme 7]

Use a method similar to Synthetic Example 5 to prepare intermediate product I-7 ((E)-9-(4-(4-bromostyryl)phenyl)-3,6-di-tert-butyl-9H-carbazole), the difference Only in that the 4-(9H-carbazol-9-yl) benzaldehyde in the synthetic example 5 is replaced by 4-(3,6-two-tertiary butyl-9H-carbazol-9-yl)benzaldehyde ( 4-(3,6-di-tert-butyl-9H-carbazol-9-yl)benzaldehyde) (0.38g, 1mmol). According to the above method, the intermediate product I-7 (0.49 g, yield 91%) was obtained as a light yellow powder.

¹ H NMR (400MHz, CDCl ₃ ): δ8.12 (d, J = 1.2Hz, 2H), 7.69 (d, J = 8.4Hz, 2H), 7.55-7.35 (m, 10H), 7.17 (d, J =16.4Hz, 1H), 7.17(d, J=16.4Hz, 1H), 1.45(s, 18H)

¹³ C NMR (100MHz, CDCl ₃ ): δ142.96, 139.03, 137.65, 136.10, 135.52, 131.85, 128.47, 128.02, 127.93, 127.77, 126.77, 123.62, 123.42, 121.52, 119.21, 1

Synthetic Example 8: Synthesis of Intermediate I-8

[Reaction scheme 8]

Use a method similar to Synthetic Example 5 to prepare intermediate product I-8 ((E)-9-(4-(4-bromostyryl)phenyl)-3,6-dimethoxy-9H-carbazole), the difference being that the synthetic 4-(9H-carbazol-9-yl) benzaldehyde in example 5 is replaced with 4-(3,6-dimethoxy-9H-carbazol-9-yl) benzaldehyde (4-(3,6 -dimethoxy-9H-carbazol-9-yl)benzaldehyde) (0.33g, 1mmol). According to the above method, the intermediate product I-7 (0.45 g, yield 93%) was obtained as a light yellow powder.

¹ H NMR (400MHz, CDCl ₃ ): δ7.68(d, J=8.0Hz, 2H), 7.53-7.48(m, 6H), 7.41-7.39(m, 2H), 7.35(d, J=8.8Hz ,2H),7.16(d,J=16.4Hz,1H),7.08(d,J=16.4Hz,1H),7.03(dd,J=2.8,9.2Hz,2H),3.93(s,6H)

¹³ C NMR (100MHz, CDCl ₃ ): δ154.06, 137.55, 136.03, 136.01, 135.44, 131.80, 128.35, 127.99, 127.90, 127.76, 126.60, 123.70, 121.49, 115.16, 110.71, 1

[Final Compound Synthesis]

Synthesis Example 9: Synthesis of Compound DPASP

[Reaction scheme 9]

The intermediate product I-1 (0.85g, 2mmol), 1-pyrene boronic acid (0.59g, 2.4mmol), tetrakis (triphenylphosphine) palladium (Pd (PPh ₃ ) ₄ ) (10mg, 0.01mmol), potassium carbonate Aqueous solution (2.0M, 3.5mL), ethanol (3.5mL) and toluene (10.5mL) were placed in a double-necked flask. Oxygen was removed and nitrogen was added, and the reaction was warmed to 110 °C and stirred for 24 hours. Remove the metal by filtration, extract with ethyl acetate (EA) and THF, collect the organic layer, remove water with magnesium sulfate (MgSO ₄ ), filter and remove the solvent by concentrating under reduced pressure, and then use column chromatography to separate (dichloro methane:hexane=1:5) to collect the solid. Sublimation was carried out at 265°C to obtain the yellow compound DPASP ((E)-4-(4-(4,6-dihydropyren-1-yl)styryl)-N,N-diphenylaniline) (0.82 g, yield 75 %).

¹ H NMR (400MHz, CDCl3, δ): 8.25-7.95 (m, 9H), 7.67 (d, J = 8Hz, 2H), 7.61 (d, J = 8Hz, 2H), 7.43 (d, J = 8.4Hz ,2H),7.26(dd,J=8.4Hz,J=7.6Hz,4H),7.18(d,J=16.4Hz,1H),7.12(d,J=8.4Hz,2H),7.11(d,J =16.4Hz, 1H), 7.07(d, J=8.4Hz, 4H), 7.01(t, J=7.6Hz, 2H).

¹³ C NMR(100MHz,CDCl ₃ ,δ):147.53,147.46,140.13,137.40,136.66,131.49,130.93,130.58,129.39,128.49,127.43,126.60,126.30,126.01,125.27,125.10,125.02,124.93,124.81, 124.68, 124.53, 123.57, 123.07.

HRMS m/z: [M] ⁺ calcd for C ₄₂ H ₂₉ N, 547.2300; found, 547.2305.

Anal.calcd for C ₄₂ H ₂₉ N: C92.11, H5.34, N 2.56; found: C 91.89, H5.32, N 2.47.

Synthesis Example 10: Synthesis of Compound DFASP

[Reaction scheme 10]

The intermediate product I-2 (0.92g, 2mmol), 1-pyrene boronic acid (0.59g, 2.4mmol), tetrakis (triphenylphosphine) palladium (Pd (PPh ₃ ) ₄ ) (10mg, 0.01mmol), potassium carbonate Aqueous solution (2.0M, 3.5mL), ethanol (3.5mL) and toluene (10.5mL) were placed in a double-necked flask. Oxygen was removed and nitrogen was added, and the reaction was warmed to 110 °C and stirred for 24 hours. Remove the metal by filtration, extract with ethyl acetate (EA) and THF, collect the organic layer, remove water with magnesium sulfate (MgSO ₄ ), filter and remove the solvent by concentrating under reduced pressure, and then use column chromatography to separate (dichloro methane:hexane=1:5) to collect the solid. Sublimation was carried out at 250°C to obtain the yellow compound DFASP ((E)-4-(4-(4,6-dihydropyren-1-yl)styryl)-N,N-bis(4-fluorophenyl)aniline)( 0.89 g, 77% yield).

¹ H NMR (400MHz, CDCl ₃ , δ): 8.23-7.98(m, 9H), 7.67(d, J=8.4Hz, 2H), 7.62(d, J=8.4Hz, 2H), 7.42(d, J ＝8.8Hz, 2H), 7.17(d, J=16Hz, 1H), 7.12-7.04(m, 5H), 7.00-6.90(m, 6H).

¹³ C NMR (100MHz, CDCl ₃ , δ): 158.00ppm (d, ¹³ C- ¹⁹ F coupling J＝242Hz, C), 147.44 (C), 143.50 (d, ¹³ C- ¹⁹ F coupling J＝2.3Hz, C), 140.12(C), 137.30(C), 136.51(C), 131.43(C), 131.18(C), 130.91(CH), 130.53(C), 128.39(C), 128.28(CH), 127.46( CH), 127.38(CH), 126.56(CH), 126.27(CH), 126.19(CH), 126.11(CH), 125.97(CH), 125.19(CH), 125.08(CH), 124.97(C), 124.87( C), 124.79(CH), 124.67(CH), 122.27(CH), 116.10(d, ¹³ C- ¹⁹ F coupling J＝22.7Hz, CH)

HRMS m/z: [M] ⁺ calcd for C ₄₂ H ₂₇ F ₂ N, 583.2112; found, 583.2109.

Anal.calcd for C ₄₂ H ₂₇ F ₂ N: C 86.43, H 4.66, N 2.40; found: C 86.31, H 4.70, N 2.37.

Synthesis Example 11: Synthesis of Compound NASP

[Reaction scheme 11]

The intermediate product I-3 (0.95g, 2mmol), 1-pyrene boronic acid (0.59g, 2.4mmol), tetrakis (triphenylphosphine) palladium (Pd (PPh ₃ ) ₄ ) (10mg, 0.01mmol), potassium carbonate Aqueous solution (2.0M, 3.5mL), ethanol (3.5mL) and toluene (10.5mL) were placed in a double-necked flask. Oxygen was removed and nitrogen was added, and the reaction was warmed to 110 °C and stirred for 24 hours. Remove the metal by filtration, extract with ethyl acetate (EA), collect the organic layer, remove water with magnesium sulfate (MgSO ₄ ), filter and remove the solvent by concentrating under reduced pressure, and then separate by column chromatography (dichloromethane: Hexane=1:5) was purified and the solid was collected. Sublimation was carried out at 295° C. to give the yellow compound NASP ((E)-N-phenyl-N-(4-(4-(pyren-1-yl)styryl)phenyl)naphthalen-1-amine) (0.85 g , yield 71%).

¹ H NMR (400MHz, CDCl ₃ , δ): 8.26-7.98(m, 10H), 7.91(d, J=8.0Hz, 1H), 7.80(d, J=8.0Hz, 1H), 7.66-7.60(m ,4H),7.51-7.46(m,2H),7.40-7.37(m,4H),7.26-6.98(m,9H).

¹³ C NMR(100MHz,CDCl ₃ ,δ):141.23,140.54,139.83,137.44,137.37,136.78,131.40,130.90,130.46,129.81,129.69,129.59,128.36,127.48,127.41,127.36,127.31,126.89,126.21, 126.11, 125.93, 125.91, 125.23, 125.01, 124.95, 124.86, 124.74, 124.65, 123.74, 123.33, 120.37, 120.14, 118.61, 109.96, 109.91.

HRMSm/z: [M] ⁺ calcd for C ₄₆ H ₃₁ N: 597.2457; found, 547.2456.

Anal.calcd for C ₄₆ H ₃₁ N:C 92.43,H5.23,N2.34; found:C 92.31,H 5.20,N2.29.

Synthesis Example 12: Synthesis of Compound PCzSP

[Reaction scheme 12]

The intermediate product I-4 (0.85g, 2mmol), 1-pyrene boronic acid (0.59g, 2.4mmol), tetrakis (triphenylphosphine) palladium (Pd (PPh ₃ ) ₄ ) (10mg, 0.01mmol), potassium carbonate Aqueous solution (2.0M, 3.5mL), ethanol (3.5mL) and toluene (10.5mL) were placed in a double-necked flask. Oxygen was removed and nitrogen was added, and the reaction was warmed to 110 °C and stirred for 24 hours. Remove the metal by filtration, extract with ethyl acetate (EA), collect the organic layer, remove water with magnesium sulfate (MgSO ₄ ), filter and remove the solvent by concentrating under reduced pressure, and then separate by column chromatography (dichloromethane: Hexane=1:5) was purified and the solid was collected. Sublimation was carried out at 275° C. to give yellow compound PCzSP ((E)-9-phenyl-3-(4-(pyren-1-yl)styryl)-9H-carbazole) (0.73 g, yield 67%) .

¹ H NMR (400MHz, CDCl ₃ , δ): 8.33-7.99(m, 11H), 7.75(d, J=8.0Hz, 2H), 7.68-7.57(m, 7H), 7.50-7.40(m, 5H) ,7.36-7.27(m,2H).

¹³ C NMR(100MHz,CDCl ₃ ,δ):141.27,140.58,139.87,137.47,137.41,136.81,131.43,130.91,129.84,129.71,129.62,128.40,127.49,127.46,127.42,127.37,127.33,126.94,126.22, 126.12, 125.94, 125.25, 125.03, 124.97, 124.89, 124.75, 124.66, 123.76, 123.33, 120.38, 120.14, 118.61, 109.98, 109.92.

HRMS m/z: [M] ⁺ calcd for C ₄₂ H ₂₇ N, 545.2143; found, 545.2138.

Anal.calcd for C ₄₂ H ₂₇ N: C 92.45, H 4.99, N 2.57; found: C 92.31, H 5.04, N 2.53.

Synthesis Example 13: Synthesis of Compound CZSSO

[Reaction Scheme 13]

The intermediate product I-5 (0.42g, 1mmol) and 4,4,5,5-tetramethyl-2-(4-phenylsulfonylphenyl)-1,3,2-dioxaborol Alkane (4,4,5,5-tetramethyl-2-(4-(phenylsulfonyl)phenyl)-1,3,2-dioxaborolane) (0.34g, 1mmol) was placed in a high-pressure tube, and carbonic acid was added into the high-pressure tube Potassium (0.49 g, 3.5 mmol) and tetrakis(triphenylphosphine)palladium (Pd(PPh ₃ ) ₄ ) (0.12 g, 0.1 mmol). Toluene (3 mL), water (1 mL) and ethanol (1 mL) were added to a high pressure tube under nitrogen atmosphere, and the above compounds were mixed. The mixture was heated and reacted at 80° C. for 1 day, and the reaction solution was filtered through Celite and silica gel. After the solvent was removed by rotary concentration, the product was purified by column chromatography (dichloromethane:n-hexane=1:1) to obtain 0.49 g of a yellow solid (yield 87%). Sublimation was carried out at a temperature of 305°C and a pressure of 9×10 ^-6 torr to obtain the yellow compound CZSSO ((E)-9-(4-(2-(4'-(phenylsulfonyl)-[1,1'- biphenyl]-4-yl)vinyl)phenyl)-9H-carbazole) (82% yield).

¹ H NMR (400MHz, CDCl ₃ ): δ8.16 (d, J=7.6Hz, 2H), 8.02-7.97 (m, 4H), 7.81-7.78 (m, 4H), 7.70-7.64 (m, 4H) ,7.61-7.53(m,5H),7.48-7.41(m,4H),7.35-7.25(m,4H)

HRMS (m/z): [M ⁺ ] calcd. for C ₃₈ H ₂₇ NO ₂ S, 561.1762; found, 561.1769

Anal.calcd for C ₃₈ H ₂₇ NO ₂ S: C, 81.26; H, 4.85; N, 2.49; found: C, 81.34; H, 4.71; N, 2.55

Synthesis Example 14: Synthesis of Compound TCZSSO

[Reaction Scheme 14]

The intermediate product I-7 (0.54g, 1mmol) and 4,4,5,5-tetramethyl-2-(4-phenylsulfonylphenyl)-1,3,2-dioxaborol Alkanes (0.34g, 1mmol) was placed in a high-pressure tube, and potassium carbonate (0.49g, 3.5mmol) and tetrakis(triphenylphosphine)palladium (0.12g, 0.1mmol) were added into the high-pressure tube. Toluene (3 mL), water (1 mL) and ethanol (1 mL) were added to a high pressure tube under nitrogen atmosphere, and the above compounds were mixed. The mixture was heated and reacted at 80° C. for 1 day, and the reaction solution was filtered through Celite and silica gel. After the solvent was removed by rotary concentration, the product was purified by column chromatography (dichloromethane:n-hexane=1:1) to obtain 0.56 g of a yellow solid (yield 83%). Sublimation is carried out at a temperature of 330° C. and a pressure of 9×10 ^-6 torr to obtain a green glassy compound TCZSSO ((E)-3,6-di-tert-butyl-9-(4-(2-(4 '-(phenylsulfonyl)-[1,1'-biphenyl]-4-yl)vinyl)phenyl)-9H-carbazole) (84% yield).

¹ H NMR (400MHz, CDCl ₃ ): δ8.16 (d, J=1.6Hz, 2H), 8.02-7.97 (m, 4H), 7.80-7.77 (m, 4H), 7.70-7.64 (m, 4H) ,7.61-7.53(m,5H),7.49(dd,J=2,8.8Hz,2H),7.42-7.39(m,2H),7.32(d,J=16.4Hz,1H),7.25(d,J =16.4Hz,1H),1.46(s,18H)

¹³ C NMR(100MHz,CDCl ₃ )：δ145.50,142.97,141.71,140.07,139.02,138.20,137.65,137.56,135.59,133.17,129.30,128.70,128.24,128.21,127.82,127.64,127.61,127.19,126.75,123.61, 123.43, 116.24, 109.22, 34.71, 31.98

HRMS (m/z): [M ⁺ ] calcd. for C ₄₆ H ₄₃ NO ₂ S, 673.3015; found, 673.3010

Anal.calcd for C ₄₆ H ₄₃ NO ₂ S: C, 81.98; H, 6.43; N, 2.08; found: C, 81.87; H, 6.41; N, 2.13

Synthesis Example 15: Synthesis of Compound OCZSSO

[Reaction Scheme 15]

The intermediate product I-8 (0.48g, 1mmol) and 4,4,5,5-tetramethyl-2-(4-phenylsulfonylphenyl)-1,3,2-dioxaborol Alkanes (0.34g, 1mmol) was placed in a high-pressure tube, and potassium carbonate (0.49g, 3.5mmol) and tetrakis(triphenylphosphine)palladium (0.12g, 0.1mmol) were added into the high-pressure tube. Toluene (3 mL), water (1 mL) and ethanol (1 mL) were added to a high pressure tube under nitrogen atmosphere, and the above compounds were mixed. The mixture was heated and reacted at 80° C. for 1 day, and the reaction solution was filtered through Celite and silica gel. After the solvent was removed by rotary concentration, the product was purified by column chromatography (dichloromethane:n-hexane=1:1) to obtain 0.52 g of a yellow solid (yield 84%). Sublimation is carried out at a temperature of 310°C and a pressure of 9×10 ^-6 torr to obtain the compound OCZSSO ((E)-3,6-dimethoxy-9-(4-(2-(4'-(phenylsulfonyl )-[1,1'-biphenyl]-4-yl)vinyl)phenyl)-9H-carbazole) (76% yield).

¹ H NMR (400MHz, CDCl ₃ ): δ8.02-7.97(m, 4H), 7.79-7.76(m, 4H), 7.69-7.63(m, 4H), 7.62-7.53(m, 7H), 7.40- 7.38(m, 2H), 7.31(d, J=16.4Hz, 1H), 7.24(d, J=16.4Hz, 1H), 7.04(dd, J=2.8, 9.2Hz, 2H)

HRMS (m/z): [M ⁺ ] calcd. for C ₄₀ H ₃₁ NO ₄ S, 621.1974; found, 621.1970

Anal.calcd for C ₄₀ H ₃₁ NO ₄ S: C, 77.27; H, 5.03; N, 2.25; found: C, 77.11; H, 4.95; N, 2.31

Synthesis Example 16: Synthesis of Compound CZSDCN

[Reaction Scheme 16]

The intermediate product I-5 (0.42g, 1mmol) and 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)isophthalonitrile (5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)isophthalonitrile) (0.25g, 1mmol) was placed in a high-pressure tube, and potassium carbonate (0.49 g, 3.5 mmol) and tetrakis(triphenylphosphine)palladium (0.12 g, 0.1 mmol). Toluene (3 mL), water (1 mL) and ethanol (1 mL) were added to a high pressure tube under nitrogen atmosphere, and the above compounds were mixed. The mixture was heated and reacted at 80° C. for 1 day, and the reaction solution was filtered through Celite and silica gel. After the solvent was removed by rotary concentration, the product was purified by column chromatography (dichloromethane:n-hexane=2:1) to obtain 0.42 g of a yellow solid (yield 89%). Sublimation was carried out at a temperature of 290°C and a pressure of 9×10 ^-6 torr to obtain the yellow compound CZSDCN ((E)-4'-(4-(9H-carbazol-9-yl)styryl)-[1,1 '-biphenyl]-3,5-dicarbonitrile) (83% yield).

¹ H NMR (400MHz, CDCl ₃ ): δ8.17-8.15 (m, 4H), 7.92 (t, J = 1.4Hz, 1H), 7.82 (d, J = 8.4Hz, 2H), 7.74 (d, J ＝8.4Hz, 2H), 7.64-7.61(m, 4H), 7.49-7.42(m, 4H), 7.38-7.26(m, 4H)

¹³ C NMR(100MHz,CDCl ₃ )：δ143.42,140.66,138.51,137.36,135.86,135.52,134.07,133.32,129.40,128.02,128.01,127.61,127.37,127.22,125.98,123.46,120.36,120.09,116.71,114.65, 109.76

HRMS (m/z): [M ⁺ ] calcd. for C ₃₄ H ₂₁ N ₃ , 471.1735; found, 471.1745

Anal.calcd for C ₃₄ H ₂₁ N ₃ : C, 86.60; H, 4.49; N, 8.91; found: C, 86.39; H, 4.23; N, 9.21

Synthesis Example 17: Synthesis of Compound CZSDPT

[Reaction Scheme 17]

The intermediate product I-6 (0.47g, 1mmol) was mixed with 2-chloro-4,6-diphenyl-1,3,5-triazine (2-chloro-4,6-diphenyl-1,3,5- triazine) (0.27g, 1mmol) was placed in a high-pressure tube, and potassium carbonate (0.49g, 3.5mmol) and tetrakis (triphenylphosphine) palladium (0.12g, 0.1mmol) were added into the high-pressure tube. Toluene (3 mL), water (1 mL) and ethanol (1 mL) were added to a high pressure tube under nitrogen atmosphere, and the above compounds were mixed. The mixture was heated and reacted at 80° C. for 1 day, and the reaction solution was filtered through Celite and silica gel. After the solvent was removed by rotary concentration, the product was purified by column chromatography (dichloromethane:n-hexane=1:1) to obtain 0.44 g of a yellow solid (yield 76%). Sublimation is carried out at a temperature of 310°C and a pressure of 9×10 ^-6 torr to obtain the yellow compound CZSDPT ((E)-9-(4-(4-(4,6-diphenyl-1,3,5-triazin -2-yl)styryl)phenyl)-9H-carbazole) (70% yield).

¹ H NMR (400MHz, CDCl ₃ ): δ8.84-8.80 (m, 5H), 8.17 (d, J = 8.4Hz, 2H), 7.83 (dd, J = 8.4, 14.8Hz, 4H), 7.68-7.60 (m,8H),7.51-7.42(m,6H),7.38-7.29(m,3H)

¹³ C NMR(100MHz,CDCl ₃ )：δ171.58,171.15,141.14,140.70,137.28,136.25,136.06,135.53,132.49,129.57,129.43,128.96,128.84,128.63,128.67,127.19,126.76,125.98,123.46,120.34, 120.05, 109.81

HRMS (m/z): [M ⁺ ] calcd. for C ₄₁ H ₂₈ N ₄ ,576.2314; found, 576.2305

_Anal.calcd for _C41H28N4 : C, _85.39 ; H, 4.89; N, 9.72; found: C, 85.07; H, 5.03; N, 9.60

[Evaluation of Properties of Compounds]

[Photophysical properties]

Table 1 shows the luminescent properties of the aromatic compounds of the above examples.

[Table 1]

From the results in Table 1, it can be seen that the fluorescence emission wavelength distribution of the aromatic compound of the above-mentioned embodiment is between 420nm and 497nm, that is to say, the aromatic compound of the above-mentioned embodiment can emit blue light, so it is suitable as a blue light-emitting material . In addition, the aromatic compounds of the above examples also have high quantum efficiency.

3A and 3B are the transient photo-excited fluorescence curves of the toluene solution containing the compound CZSSO under air and nitrogen respectively. 4A and 4B are the transient photo-excited fluorescence curves of the toluene solution containing the compound TCZSSO under air and nitrogen respectively. 5A and 5B are the transient photo-excited fluorescence curves of the toluene solution containing the compound OCZSSO under air and nitrogen respectively. 6A and 6B are the transient photo-excited fluorescence curves of the toluene solution containing the compound CZSDCN under air and nitrogen respectively. 7A and 7B are the transient photo-excited fluorescence curves of the toluene solution containing the compound CZSDPT under air and nitrogen respectively.

In general, an organic light-emitting diode injects charges from an anode and a cathode into a light-emitting substance, and emits light through the generated excitons in an excited state. Of the generated excitons, 25% are excited in the singlet excited state, and the remaining 75% are excited in the triplet excited state, and only the excitons in the singlet excited state can emit fluorescence. However, certain luminescent materials have the characteristic of delayed fluorescence, and the source of the fluorescence emission is mainly from the exciton radiative transition from the triplet excited state to the singlet excited state. Delayed fluorescence can be divided into triplet-triplet annihilation (Triplet-Triplet Annihilation, TTA) delayed fluorescence and thermally activated delayed fluorescence (TADF), where TTA delayed fluorescence is the combination of two triplet excited states. The exciton is transformed into a singlet excited state exciton that can radiatively transition through the collision quenching process, so that the triplet exciton is partially reused; while the TADF delayed fluorescence is converted into a triplet excited state exciton by thermal energy. Absorption, through the reverse intersystem crossing into a singlet excited state and emission of fluorescence.

It is currently known that luminescent materials with TADF characteristics will have a delayed fluorescence phenomenon of more than 500 ns in aqueous solution. From the results of Fig. 3 to Fig. 7, it can be seen that no matter in the case of air or nitrogen, the films containing the aromatic compounds (CZSSO, TCZSSO, OCZSSO, CZSDCN, CZSDPT) of the present invention are photoexcited in aqueous solution. The phenomenon of delayed fluorescence occurs. That is to say, the aromatic compounds CZSSO, TCZSSO, OCZSSO, CZSDCN, and CZSDPT of the present invention are not luminescent materials with TADF characteristics.

[Thermal stability properties]

In the thermal stability test, a thermogravimetric thermal difference analyzer is used to conduct the thermal stability test at a heating rate of 10° C./min to 20° C./min.

Table 2 shows the results of thermal stability tests of aromatic compounds.

[Table 2]

compound T _g (°C) T _c (°C) T _m (°C) _Td (°C) DPASP 96 N.D. 270 439 DFASP N.D. N.D. 246 410 NASP 106 N.D. 226 452 PPML N.D. N.D. 204 431 CZSO N.D. N.D. 285 407 TCZSSO 148 226 260 424 OCZSSO 111 N.D. 246 436 CZSDCN 147 N.D. 288 405 CZSDPT 76 N.D. 298 437

T _g : glass transition temperature; T _c : crystallization temperature; T _m : melting point temperature; T _d : thermal decomposition temperature; ND: not detected.

From the results in Table 2, it can be seen that the thermal decomposition temperature of the aromatic compounds in this case is higher than 400° C., and has excellent thermal stability.

[Manufacturing of organic light-emitting diodes]

Experimental example 1

DMPPP was used as the host luminescent material, and the compound DPASP obtained in Synthesis Example 9 was used as the guest luminescent material (ie dopant) to fabricate an organic light emitting diode.

Specifically, the fabrication process of OLEDs is as follows: First, N,N'-di-(1-naphthyl)-N,N'- Diphenylbiphenyl-4,4'-ethylenediamine (N,N'-di(naphthalen-1-yl)-N,N'-diphenylbiphenyl-4,4'-diamine, NPB) (60nm) and doped NPB (10 nm) doped with 3% compound DPASP to form a hole transport layer. Next, deposit a host doped with 5% compound DPASP on the hole transport layer to emit light Material DMPPP (15nm) to form the light emitting layer. Then, deposit two (2-methyl-8-quinolinolate)-4-(phenylphenol) aluminum (bis(2-methyl-8-quinolinolate)-4-(phenylphenolato)aluminum, BAlq) on the light-emitting layer (20nm) to form an electron transport layer. After that, LiF (1nm) and Al (100nm) are sequentially deposited on the electron transport layer to form a cathode. So far, the fabrication of the organic light emitting diode of this experimental example is completed. The above organic light emitting diode has the following structure: ITO/NPB(60nm)/NPB:3%DPASP(10nm)/DMPPP:3%DPASP(15nm)/BAlq(20nm)/LiF(1nm)/Al(100nm).

Experimental example 2

An organic light emitting diode was formed using a method similar to Experimental Example 1, the difference being that the compound DFASP obtained in Synthesis Example 10 was used as a dopant for the hole transport layer and the light emitting layer.

Experimental example 3

An organic light emitting diode was formed using a method similar to Experimental Example 1, the difference being that the compound NASP obtained in Synthesis Example 11 was used as a dopant for the hole transport layer and the light emitting layer.

Experimental example 4

An organic light emitting diode was formed using a method similar to Experimental Example 1, the difference being that the compound PCzSP obtained in Synthesis Example 12 was used as a dopant for the hole transport layer and the light emitting layer.

Experimental example 5

Using CBP as the host luminescent material, and using the compound DPASP obtained in Synthesis Example 9 as the guest luminescent material (ie dopant) to fabricate an organic light emitting diode.

Specifically, the fabrication process of OLEDs is as follows: First, NPB (30nm) and N,N',N"-tris(N-carbazole) are sequentially deposited on an ITO glass substrate (150nm) as an anode Base) triphenylamine (4,4',4"-tri(N-carbazolyl) triphenylamine, TCTA) (20nm) to form a hole transport layer. Next, the host luminescent material CBP (30nm) doped with 3% compound DPASP is deposited on the hole transport layer to form a luminescent layer. Then, deposit 1,3,5-tris[(3-pyridyl)-3-phenyl]benzene (1,3,5-tris[(3-pyridyl)-3-phenyl]benzene, TmPyPb ) (30nm) to form an electron transport layer. After that, LiF (1nm) and Al (100nm) are sequentially deposited on the electron transport layer to form a cathode. So far, the fabrication of the organic light emitting diode of this experimental example is completed. The above organic light emitting diode has the following structure: ITO/NPB(30nm)/TCTA(20nm)/CBP:3%DPASP(30nm)/TmPyPb(30nm)/LiF(1nm)/Al(100nm).

Experimental example 6

An organic light emitting diode was formed using a method similar to Experimental Example 5, the only difference being that the concentration of the doping compound DPASP was 5%.

Experimental example 7

An organic light emitting diode was formed using a method similar to that of Experimental Example 5, the only difference being that the concentration of the doping compound DPASP was 10%.

Experimental example 8

The organic light-emitting diode was formed using a method similar to Experimental Example 5, the only difference being that the compound DFASP obtained in Synthesis Example 10 was used as the dopant of the light-emitting layer, and the concentration of the compound DFASP was 5%.

Experimental example 9

An organic light emitting diode was formed using a method similar to Experimental Example 5, the only difference being that the compound NASP obtained in Synthesis Example 11 was used as the dopant of the light emitting layer, and the concentration of the compound NASP was 5%.

Experiment 10

An organic light emitting diode was formed using a method similar to Experimental Example 5, the only difference being that the compound PCzSP obtained in Synthesis Example 12 was used as the dopant of the light emitting layer, and the concentration of the compound PCzSP was 5%.

Experiment 11

DMPPP was used as the host luminescent material, and the compound CZSSO obtained in Synthesis Example 13 was used as the guest luminescent material (ie dopant) to fabricate an organic light emitting diode.

Specifically, the manufacturing process of the OLED is as follows: First, NPB (10nm) and TCTA (40nm) are sequentially deposited on the ITO glass substrate (150nm) as the anode to form a hole transport layer. Next, the host light-emitting material DMPPP (30nm) doped with 10% compound CZSSO is deposited on the hole transport layer to form a light-emitting layer. Then, deposit TmPyPb (40nm) on the light emitting layer to form an electron transport layer. After that, LiF (1nm) and Al (100nm) are sequentially deposited on the electron transport layer to form a cathode. So far, the fabrication of the organic light emitting diode of this experimental example is completed. The above organic light emitting diode has the following structure: ITO/NPB(10nm)/TCTA(40nm)/DMPPP:10%CZSSO(30nm)/TmPyPb(40nm)/LiF(1nm)/Al(100nm).

Experiment 12

An organic light emitting diode was formed using a method similar to that of Experimental Example 11, the only difference being that the compound TCZSSO obtained in Synthetic Example 14 was used as the dopant of the light emitting layer.

Experiment 13

An organic light emitting diode was formed using a method similar to that of Experimental Example 11, the difference being that the compound OCZSSO obtained in Synthetic Example 15 was used as a dopant for the light emitting layer.

Experiment 14

An organic light emitting diode was formed using a method similar to that of Experimental Example 11, the only difference being that the compound CZSDCN obtained in Synthetic Example 16 was used as a dopant for the light emitting layer.

Experiment 15

An organic light emitting diode was formed using a method similar to that of Experimental Example 11, the difference being that the compound CZSDPT obtained in Synthetic Example 17 was used as a dopant for the light emitting layer.

Experiment 16

The organic light-emitting diode was formed using a method similar to that of Experimental Example 11, the only difference being that CBP was used as the host light-emitting material, and the concentration of the compound CZSSO was 7%.

Experiment 17

Use a method similar to Experimental Example 11 to form an organic light-emitting diode, the only difference is that CBP is used as the host light-emitting material, and the compound TCZSSO obtained in Synthesis Example 14 is used as the dopant of the light-emitting layer, wherein the concentration of the compound TCZSSO 7%.

Experiment 18

Use a method similar to Experimental Example 11 to form an organic light-emitting diode, the only difference is that CBP is used as the host light-emitting material, and the compound OCZSSO obtained in Synthesis Example 15 is used as the dopant of the light-emitting layer, wherein the concentration of the compound OCZSSO 7%.

Experiment 19

Use a method similar to Experimental Example 11 to form an organic light-emitting diode, the only difference is that CBP is used as the host light-emitting material, and the compound CZSDCN obtained in Synthesis Example 16 is used as the dopant of the light-emitting layer, wherein the concentration of the compound CZSDCN 7%.

Experiment 20

Use a method similar to Experimental Example 11 to form an organic light-emitting diode, the only difference is that CBP is used as the host light-emitting material, and the compound CZSDPT obtained in Synthesis Example 17 is used as the dopant of the light-emitting layer, wherein the concentration of the compound CZSDPT 7%.

comparative example

An organic light emitting diode was formed using a method similar to that of Experimental Example 5, the only difference being that there was no dopant in the light emitting layer.

[Efficacy Evaluation of Organic Light-Emitting Diodes]

FIG. 8 is the transient electroluminescence curves of the organic light emitting diodes of Experimental Example 1 to Experimental Example 4. FIG. FIG. 9 is the transient electroluminescence curves of organic light emitting diodes of Experimental Example 5 to Experimental Example 7 and Comparative Example. FIG. 10 is the transient electroluminescence curves of the organic light emitting diodes of Experimental Example 8 to Experimental Example 10. FIG. FIG. 11 is a transient electroluminescence curve of the organic light emitting diode of Experimental Example 18. FIG.

From the results of FIG. 8 to FIG. 11 , it can be seen that compared with the light-emitting diode of the comparative example, which does not have the phenomenon of delayed fluorescence, experimental examples 1 to 10 and experimental example 18 have the phenomenon of delayed fluorescence.

It should be particularly noted here that since the aromatic compound OCZSSO is not known to be a luminescent material with TADF characteristics from the results of the above-mentioned FIG. 5A and FIG. is from TTA delayed fluorescence.

12 is the luminance-external quantum efficiency curves of the organic light emitting diodes of Experimental Example 11 to Experimental Example 15.

From the results in FIG. 12 , it can be seen that the external quantum efficiencies of the organic light emitting diodes of experimental examples 11 to 15 do not decrease with the increase of luminance, indicating that the organic light emitting diodes of experimental examples 11 to 15 have long life characteristics.

Table 3 shows the results of testing the performance of the organic light emitting diodes of Experimental Example 1 to Experimental Example 20 and Comparative Example.

[table 3]

V _d : driving voltage; EQE: external quantum efficiency; L _max : maximum brightness; CE: current efficiency; PE: power efficiency; CIE: chromaticity coordinates

From the results in Table 3, it can be seen that the maximum emission wavelength of the organic light-emitting diodes in Experimental Example 1 to Experimental Example 20 is in the range of 440 nm to 476 nm, so they have the characteristic of emitting blue light.

In addition, since the organic light emitting diodes of Experimental Example 1 to Experimental Example 20 have the aromatic compound of the present invention in the light emitting layer compared to the organic light emitting diode of the comparative example which does not have a dopant in the light emitting layer, it is obvious that It has high external quantum efficiency, maximum brightness, current efficiency and power efficiency.

In summary, the aromatic compound of the present invention has the characteristics of blue light emission, high quantum efficiency, and excellent thermal stability. In addition, the aromatic compound of the present invention can be doped in the light-emitting layer or the hole transport layer of the organic light-emitting diode to improve the external quantum efficiency, maximum brightness, current efficiency, power efficiency and lifetime of the organic light-emitting diode.

Although the present invention has been disclosed above with the embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, this The scope of protection of the invention should be determined by the appended claims.

Claims (12)

1. An aromatic compound, characterized in that, is represented by the following chemical formula 1: [chemical formula 1] In Chemical Formula 1, R ₁ and R ₂ are each independently hydrogen, halogen, C ₁ -C ₆ alkyl or aryl; m is an integer of 0 or 1; A is a substituted or unsubstituted carbazolyl Ar or is _an organic amino group; and Ar ₂ is substituted or unsubstituted pyrenyl, substituted or unsubstituted sulfonyl, substituted or unsubstituted triazinyl or substituted or unsubstituted 2. The aromatic compound according to claim 1, wherein the aromatic compound is represented by the following chemical formula 2: [chemical formula 2] In Chemical Formula 2, Ar ₃ is selected from the following structural formulas, The remaining substituents are the same as defined in Chemical Formula 1. 3. The aromatic compound according to claim 1, wherein the aromatic compound is represented by the following chemical formula 3: [chemical formula 3] In Chemical Formula 3, Ar ₄ is selected from the following structural formulas, The remaining substituents are the same as defined in Chemical Formula 1. 4. aromatic compound according to claim ₁ , is characterized in that, Ar Be selected from following structural formula, 5. An organic light emitting diode, characterized in that it comprises: cathode; anode; and A light-emitting layer is disposed between the cathode and the anode, the light-emitting layer comprising the aromatic compound according to any one of claims 1-4. 6. The organic light emitting diode according to claim 5, wherein the organic light emitting diode is a blue light emitting diode. 7. The organic light emitting diode according to claim 5, wherein the light emitting layer comprises a host light emitting material and a guest light emitting material. 8. The organic light emitting diode according to claim 7, wherein the host luminescent material comprises the aromatic compound. 9. The organic light emitting diode according to claim 7, wherein the guest luminescent material comprises the aromatic compound. 10. The organic light emitting diode according to claim 7, characterized in that, the host luminescent material comprises 1-(2,5-dimethyl-4-(1-pyrenyl)phenyl)pyrene, 4,4 '-N,N'-dicarbazole-biphenyl or 2-(3-(pyren-1-yl)phenyl)biphenylene. 11. The organic light emitting diode according to claim 5, further comprising at least one auxiliary layer, the auxiliary layer is selected from a hole injection layer, a hole transport layer, a hole blocking layer, an electron injection layer, an electron The group consisting of transport layer and electron blocking layer. 12 . The organic light emitting diode according to claim 11 , wherein the at least one auxiliary layer comprises the aromatic compound according to any one of claims 1 to 4 .