Preparation and application of phosphorescent doped material

Abstract

The invention belongs to the field of organic photoelectric materials, and provides a phosphorescent doped material, a preparation method thereof and an organic electroluminescent device containing the phosphorescent doped material. The structure of the phosphorescent doping material is as shown in formula I: # imgabs0. The organic electroluminescent device prepared from the phosphorescent doping material has the technical effects of high luminous efficiency, long service life and improvement of driving voltage.

Description

Technical Field

[0001] The invention relates to the field of organic synthesis and organic photoelectric materials, and more specifically to the preparation of a red phosphorescent doped material and a light-emitting device. Background Art

[0002] OLED has the advantages of low driving voltage, high brightness, high efficiency, etc., and has broad application prospects in the fields of solid-state lighting and flat panel displays. Therefore, it has attracted widespread attention from researchers in recent years.

[0003] The doping materials of the OLED light-emitting part are mainly organic phosphorescent materials, which can be roughly divided into three types: red, blue and green. Recent studies have found that organic phosphorescent materials will produce singlet excitons and triplet excitons under the action of driving voltage, which is different from traditional phosphorescent materials that only rely on singlet excitons. Studies have also found that organic phosphorescent materials can increase the internal quantum efficiency to 100% by adding heavy metals. These metals promote stable spin-orbit coupling and promote the mixing of singlet and triplet states. Therefore, in recent years, people have devoted themselves to the research of heavy metal coordinated organic phosphorescent materials, especially the research of metal iridium complex organic phosphorescent materials.

[0004] Among the three primary color devices of green, blue and red, the performance of green and blue devices is generally better than that of red devices, which basically meets the needs of industrialization; at present, the research progress of red organic electroluminescent materials and devices is relatively slow. Because the energy gap of red light materials is narrow, it is difficult to match the energy levels between the host and guest materials, resulting in generally low efficiency and poor color purity of red light devices. However, red light materials are essential materials for obtaining white light devices. Therefore, how to obtain high-performance red light materials is crucial to the development of organic electroluminescent devices. Summary of the invention

[0005] The object of the present invention is to provide a preparation method and application of a red light iridium metal heterocyclic complex material. A red phosphorescent organic photoelectric material with a large number of connected ring structures is prepared by reacting a specific heterocyclic derivative of 2-phenylpyridine with iridium metal and a diketone monomer. The material can be applied to an electroluminescent device as a light-emitting part of an organic electroluminescent device, which can improve the luminous efficiency, reduce the driving voltage, and extend the service life of the device.

[0006] To achieve the above object, the present invention adopts the following technical solution:

[0007] The first technical purpose of the present invention is to provide a phosphorescent doping material, the general structural formula of which is shown in Formula I:

[0008]

[0009] wherein R1 to R8 each independently represent hydrogen, a deuterium atom, a halogen, a hydroxyl group, a cyano group, a nitro group, an amino group, a sulfonic acid group, a substituted or unsubstituted C1-C 50 Alkyl, substituted or unsubstituted C6-C 50 Aryl, substituted or unsubstituted C6-C 50 Heteroaryl, substituted or unsubstituted C3-C 50 Cycloalkyl, substituted or unsubstituted C1-C 50 Alkoxy, substituted or unsubstituted C1-C 50 Alkylamino, substituted or unsubstituted C2-C 50 Alkenyl or alkyne, substituted or unsubstituted C4-C 50 Heterocyclyl, substituted or unsubstituted C 10 -C 50 Condensed ring group, substituted or unsubstituted C5-C 50 Spirocyclyl, substituted or unsubstituted C1-C 50 Silane, substituted or unsubstituted C1-C 50 The germanium alkyl group, the substituents at the positions of R1 to R8 are the same or different. The positions of R1 to R4 are fixed; the positions of R5 to R8 are any positions of the benzene ring, and the number of the substituents of R5 to R8 is 0 to 4.

[0010] Furthermore, each of R1 to R3 is independently selected from hydrogen and the following groups:

[0011]

[0012] in Represents the connection location

[0013] Furthermore, the R5 to R8 each independently represent hydrogen, deuterium, cyano, fluorine, trimethylsilyl, trimethylgermanyl, substituted or unsubstituted C1-C 15 Alkyl, substituted or unsubstituted C3-C 15 Cycloalkyl, substituted or unsubstituted C3-C 15 Alkoxy, substituted or unsubstituted C4-C 15 Heterocyclic, substituted or unsubstituted C6-C 15 Aryl, substituted or unsubstituted C 10 -C 20 The fused ring group, R5 to R8 are the same or different.

[0014] Furthermore, substituted or unsubstituted C1-C 15 The alkyl group includes any one of methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, isobutyl, pentyl, isopentyl, neopentyl, hexyl, 2-methylpentyl, 3-methylpentyl, 2,3-dimethylbutyl and 2,2-dimethylbutyl.

[0015] Furthermore, substituted or unsubstituted C6-C 15 The aryl group includes any one of a phenyl group, a tolyl group, a chlorophenyl group, a bromophenyl group, a fluorophenyl group, a biphenyl group, a terphenyl group, a naphthyl group, an anthracenyl group, and a phenanthryl group.

[0016] Furthermore, the substituted or unsubstituted C1-C 15 The cycloalkyl group includes any one of cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and cyclooctyl.

[0017] Furthermore, the substituted or unsubstituted C1-C 15 The alkoxy group includes any one of a methoxy group, an ethoxy group, a propoxy group, and a phenoxy group.

[0018] Furthermore, substituted or unsubstituted C1-C 15 The heterocyclic group includes an aromatic or non-aromatic cyclic group containing at least one heteroatom, wherein the heteroatom is selected from one or more combinations of O, S, N, P, B, Si and Ge.

[0019] Furthermore, the red light metal complex material is characterized in that the R1 to R8 can be arbitrarily combined to form a substituted or unsubstituted condensed ring, and the substituents that do not form a condensed ring include hydrogen, deuterium, cyano, substituted or unsubstituted C1-C 50 Alkyl, substituted or unsubstituted C1-C 50 Aryl, substituted or unsubstituted C3-C 15 Cycloalkyl, substituted or unsubstituted C4-C 50 Heterocyclic, substituted or unsubstituted C 10 -C 20 A fused ring group, a substituted or unsubstituted C5-C 50 The spirocyclic group may or may not contain any one or more of O, S, N, P, B, Si and Ge in the formed condensed ring.

[0020] Furthermore, the hydrogen atoms in the groups or substituent groups of R1 to R8 can be deuterated. Furthermore, the specific structure of the iridium metal heterocyclic complex luminescent material is:

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[0075] A method for preparing a red light metal complex material comprises the following steps:

[0076] S1. Add a compound of formula II, bipyralidinol borate and potassium acetate into a three-necked flask, use 1,4-dioxane as a solvent, replace nitrogen, and then add a catalyst under a nitrogen atmosphere. After reacting at a certain temperature for a period of time, obtain a compound of formula III by rotary evaporation and passing through a silica gel funnel.

[0077] S2. At room temperature, a compound of formula III, a compound of formula IV, potassium carbonate, tetrahydrofuran, anhydrous ethanol and water as solvents are added to a three-necked flask, and after replacing the nitrogen, tetrakis(triphenylphosphine)palladium is added. After reacting at a certain temperature for a period of time, a compound of formula V is obtained by liquid separation and column chromatography.

[0078] S3. Synthesis of compounds of formula VI:

[0079] ① Add the compound of formula V into a high-pressure reactor, add a solvent to replace nitrogen twice, add a metal-based catalyst, and then replace nitrogen twice. Under high temperature and high pressure, introduce hydrogen to react for a period of time to obtain a product compound of formula VI. Add acetic acid and sulfuric acid to the obtained compound of formula VI, react at high temperature for a period of time, and add ethanol and water to obtain a compound of formula VII.

[0080] ② Under a nitrogen atmosphere, the compound of formula V is dissolved in a tetrahydrofuran solvent, a Grignard reagent solution is added at low temperature, the reaction is carried out at room temperature for a period of time, and then a compound of formula VI is obtained; then acetic acid and sulfuric acid are added to the obtained compound of formula VI, the reaction is carried out at high temperature for a period of time, and ethanol and water are added thereto to obtain a compound of formula VII.

[0081] S4. Under a nitrogen atmosphere, add the compound of formula VII and iridium trichloride into a three-necked flask, and react at a certain temperature for a period of time to obtain a compound of formula VIII.

[0082] S5. Add the compound of formula VIII and anhydrous potassium carbonate into a three-necked flask, use ethylene glycol ethyl ether as solvent, replace nitrogen, add the compound of formula IX, react at high temperature for a period of time, filter and pass through a silica gel funnel to obtain a compound of formula I. The synthesis route is as follows:

[0083]

[0084] Preferably, in the step S1, X in the structure of the compound of formula II may be chlorine or bromine;

[0085] Furthermore, in the step S1, the ratio of the amount of the compound of formula II to the amount of the bipyralidone borate is 1:(1-2.5), and the preferred ratio is 1:2;

[0086] Further, the catalyst in step S1 includes tris(dibenzylideneacetone)dipalladium (DBA palladium), and 2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl (X-phos) or 2-dicyclohexylphosphine-2',6'-dimethoxybiphenyl (S-phos), wherein the amount of DBA palladium added is 0.5% to 2% of the amount of the compound of formula II, and the preferred amount is 1%; the amount of X-phos and S-phos added is 5% to 10% of the amount of the compound of formula II, and the preferred amount is 8%;

[0087] Furthermore, the ratio of the amount of potassium acetate to the compound of formula II in step S1 is (2-3):1, and the preferred ratio is 2.5:1;

[0088] Preferably, the amount of 1,4-dioxane added in step S1 is (15-25) equivalents of the compound of formula II;

[0089] Preferably, the reaction temperature in step S1 is 90° C. to 110° C., and the reaction time is 12 h to 24 h.

[0090] Preferably, X in the structure of the compound of formula IV in step S2 may be chlorine or bromine;

[0091] Furthermore, in the step S2, the ratio of the compound of formula III to the compound of formula IV is (1-1.5):1, wherein the optimal ratio is 1.2:1;

[0092] Preferably, the amount of tetrakis(triphenylphosphine)palladium added in step S2 is 2% to 4% of the amount of the compound of formula IV;

[0093] Furthermore, the ratio of the amount of anhydrous potassium carbonate to the compound of formula IV in step S2 is (2-4):1, and the preferred ratio is 3:1;

[0094] Preferably, in step S2, the amount of tetrahydrofuran added is (8-12) equivalents of the compound of formula IV, and the amount of anhydrous ethanol and water added is the same, which is 0.5 times the volume of tetrahydrofuran;

[0095] Preferably, the reaction temperature in step S2 is 70° C. to 100° C., and the reaction time is 12 h to 24 h.

[0096] Preferably, method ① in step S3 is applicable to compounds of formula I structure in which the substituent at the R4 position is a hydrogen atom, and method ② is applicable to compounds of formula I structure in which the substituent at the R4 position is other substituents;

[0097] Furthermore, the solvent in the method ① of step S3 is methanol or anhydrous ethanol;

[0098] Preferably, the metal-based catalyst in the method ① of step S3 includes a copper-based catalyst, a nickel-based catalyst and a palladium-based catalyst;

[0099] Furthermore, the reaction temperature in the S3 step method ① is 80°C to 120°C, and the reaction pressure is 4 to 6Mpa;

[0100] Furthermore, in the step S3, the amount of acetic acid added is 10 to 15 equivalents of the compound of formula VI, and the amount of concentrated sulfuric acid added is 0.5% to 1.5% of the volume of acetic acid;

[0101] Furthermore, the reaction temperature of the compound of formula VI in step S3 is 85°C to 100°C, and the reaction time is 1.5h to 2.5h;

[0102] Preferably, the amount of anhydrous ethanol and water added to obtain the solid compound of formula VII in step S3 and the volume of acetic acid;

[0103] Preferably, the low temperature reaction temperature in the method ② of step S3 is 0°C, and the reaction time at room temperature is 4 to 8 hours;

[0104] Furthermore, in the step S4, the molar ratio of the compound of formula VII to iridium trichloride is (2-3):1, and the preferred ratio is 2.5:1;

[0105] Preferably, the solvent used in the reaction in step S4 is ethylene glycol ethyl ether;

[0106] Preferably, the reaction temperature in step S4 is 120° C. and the reaction time is 24 h to 48 h.

[0107] Furthermore, in the step S5, the molar ratio of the compound of formula VIII to the compound of formula IX is 1:(2-3.5, preferably 1:3;

[0108] Furthermore, the ratio of the amount of anhydrous potassium carbonate to the compound of formula VIII in step S5 is (8-12):1, and the preferred ratio is 10:1;

[0109] Preferably, the reaction temperature in step S5 is 120° C. and the reaction time is 24 h to 48 h.

[0110] The present invention also provides an application of a red light metal complex material for preparing an organic electroluminescent device, which comprises a substrate, and an anode layer, a hole transport layer, an organic light emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer and a cathode layer sequentially deposited on the substrate;

[0111] Furthermore, the organic light-emitting layer includes a main material and a doping material, and the doping material is the above-mentioned red light metal complex material.

[0112] Preferably, the weight ratio of the host material to the doping material is 90:10 to 99.5:0.5.

[0113] Preferably, the thickness of the organic light-emitting layer is 25-35 nm.

[0114] It can be seen from the above technical solution that, compared with the prior art, the present invention provides an iridium metal heterocyclic complex luminescent material and a preparation method and device thereof, which have the following advantages:

[0115] The red light metal complex material provided by the present invention is prepared by reacting a specific heterocyclic derivative of 2-phenylpyridine with iridium metal and a diketone monomer. The prepared metal complex has a large number of connected ring structures, which make its chemical properties relatively stable and at the same time make it have a specific phosphorescence wavelength, and can produce red light phosphorescence. When it is applied to an electroluminescent device, due to its special structural properties, the driving voltage of the organic electroluminescent device can be reduced, the luminous efficiency can be improved, and the service life of the light-emitting device can be extended. Specific implementation plan

[0116] The present invention will be described clearly and completely below through specific embodiments.

[0117] Example 1

[0118] The synthetic route of formula I-1 is as follows:

[0119]

[0120] S1. Add formula II-1 (0.05 mol, 8.1 g) (CAS No.: 25586-43-0), pinacol diboron (0.1 mol, 25.4 g) and potassium acetate (0.125 mol, 12.3 g) into a three-necked flask, 160 ml of 1,4-dioxane as a solvent, replace the nitrogen, and then add (0.5 mmol, 0.46 g) of DBA palladium and (4.0 mmol, 1.9 g) of X-phos under a nitrogen atmosphere, and then react at 100°C for 20 hours, and then obtain formula III-1 (9.6 g, yield 76%) by rotary evaporation and silica gel funnel.

[0121] S2. At room temperature, add formula III-1 (0.05 mol, 12.7 g), formula IV (0.042 mol, 10.8 g) (CAS No.: 133609-32-2) and potassium carbonate (0.125 mol, 17.3 g), 108 ml of tetrahydrofuran, 54 ml of anhydrous ethanol and 54 ml of water as solvent into a three-necked flask, replace the nitrogen and add tetrakis(triphenylphosphine)palladium (1.25 mmol, 1.44 g), then react at 100°C for 24 hours, and obtain formula V-1 (9.08 g, yield 71%, HPLC: 99.4%) by separation and column chromatography.

[0122] S3. Synthesis of Formula VI-1:

[0123] Formula V-1 (0.03 mol, 9.2 g) was added to a high-pressure reactor, and anhydrous ethanol was added to replace nitrogen twice, and a copper-based catalyst was added, and then nitrogen was replaced twice. Under the conditions of 90°C and 5 MPa, hydrogen was introduced to react for a period of time, and the product VI-1 (8.6 g yield 93%) was obtained by column chromatography. 86 ml of acetic acid and 0.86 ml of concentrated sulfuric acid were added to the obtained formula VI-1, and the reaction was carried out at 90°C for 2.5 hours, and then 86 ml of ethanol and 86 ml of water were added to obtain formula VII-1.

[0124] S4. Under a nitrogen atmosphere, add formula Ⅶ-1 (0.05 mol, 14.6 g) and iridium trichloride (0.02 mol, 6.5 g) into a three-necked flask, then add 146 ml of ethylene glycol ether, and react at 120°C for 48 hours to obtain formula Ⅷ-1.

[0125] S5. Add formula VIII-1 (0.005 mol, 8.1 g) and anhydrous potassium carbonate (0.05 mol, 6.9 g) into a three-necked flask, 81 ml of ethylene glycol ether as solvent, replace nitrogen, add formula IX-1 (0.015 mol, 3.2 g) (CAS No.: 872802-98-7), react at 120°C for 48 hours, and obtain formula I-1 (7.0 g, yield 74%, HPLC: 99.4%) after suction filtration and passing through a silica gel funnel.

[0126] The results of mass spectrometry and elemental analysis of compound I-1 are shown below:

[0127] Test value: 984.46.

[0128] Elemental analysis: calculated values ​​are C: 69.56; H: 4.81; Ir: 19.53; N: 2.85; O: 3.25; measured values ​​are C: 69.13; H: 4.79; N: 2.93; O: 3.47;

[0129] NMR data: 1H NMR(400MHz,Chloroform-d)δ8.85(d,2H),8.17(d,2H),8.11(d,2H),8.07–8.02(m,2H),7.99–7.92(m,2H),7.92–

[0130] 7.85(m,2H),7.80–7.75(m,2H),7.60(dd,2H),7.46(d,2H),7.40–

[0131] 7.33(m,4H),6.22(d,2H),5.94(d,1H),2.70(tq,1H),2.54–2.43(m,1H),1.67–1.48(m,8H),0.92–0.85(m,12H).

[0132] Example 2

[0133] S1. Add formula II-2 (0.05 mol, 10.2 g) (PubChem CID: 59798312), pinacol diboron (0.1 mol, 25.4 g) and potassium acetate (0.125 mol, 12.3 g) into a three-necked flask, 200 ml of 1,4-dioxane as a solvent, replace the nitrogen, and then add (0.5 mmol, 0.46 g) of DBA palladium and (4.0 mmol, 1.9 g) of X-phos under a nitrogen atmosphere, and then react at 100 ° C for 20 hours, and then obtain formula III-2 (10.8 g, yield 73%) by rotary evaporation and silica gel funnel.

[0134] S2. At room temperature, add formula III-2 (0.05 mol, 14.8 g), formula IV (0.042 mol, 10.8 g) and potassium carbonate (0.125 mol, 17.3 g), 150 ml of tetrahydrofuran, 75 ml of anhydrous ethanol and 75 ml of water as solvent into a three-necked flask, replace the nitrogen and add tetrakis(triphenylphosphine)palladium (1.25 mmol, 1.44 g), then react at 100°C for 24 hours, and obtain formula V-2 (9.89 g, yield 68%, HPLC: 99.2%) by separation and column chromatography.

[0135] S3. Synthesis of Formula VI-2:

[0136] Formula V-2 (0.03 mol, 10.5 g) was added to a three-necked flask, dissolved in tetrahydrofuran, 1M methylmagnesium bromide tetrahydrofuran solution (80 ml) was added at low temperature, reacted at room temperature for 5 h, then 150 ml of saturated ammonium chloride aqueous solution was added for separation, the organic phase was extracted twice with brine, and then spin-dried to obtain formula VI-2. 110 ml of acetic acid and 1.1 ml of concentrated sulfuric acid were added to the prepared VI-2, reacted at 90 ° C for 2.5 h, and then 110 ml of ethanol and 110 ml of water were added to obtain formula VII-2 (6.9 g, yield 67%).

[0137] The synthetic route of formula I-215 is as follows:

[0138]

[0139] S4. Under a nitrogen atmosphere, add formula Ⅶ-2 (0.03 mol, 10.4 g) and iridium trichloride (0.012 mol, 4.3 g) into a three-necked flask, then add 105 ml of ethylene glycol ether, and react at 120°C for 48 hours to obtain formula Ⅷ-2.

[0140] S5. Add formula VIII-2 (0.005 mol, 9.2 g) and anhydrous potassium carbonate (0.05 mol, 6.9 g) into a three-necked flask, 90 ml of ethylene glycol ethyl ether as solvent, replace nitrogen, add formula IX-2 (0.015 mol, 3.6 g) (CAS No.: 865193-73-3), react at 120°C for 48 hours, and obtain formula I-215 (7.9 g, yield 71%, HPLC: 99.3%) after suction filtration and passing through a silica gel funnel.

[0141] The results of mass spectrometry and elemental analysis of compound formula I-215 are shown below:

[0142] Test value: 1124.91.

[0143] Elemental analysis: calculated values ​​are C:71.56; H:6.01; Ir:17.09; N:2.49; O:2.85; measured values ​​are C:71.04; H:6.18; N:2.33; O:2.37;

[0144] NMR data: 1H NMR(400MHz,Chloroform-d)δ8.89(d,2H),8.14(dd,2H),7.95(d,2H),7.85(d,2H),7.74(td,4H),7.65(t,2H),7.41(dd,2H),7.35(td,2H) ,7.29(td,2H),5.96(d,1H),3.47–3.39(m,2H),1.68–1.61(m,8H),1. 51(s,6H),1.39(d,6H),1.34(d,6H),1.06(d,6H),0.89–0.80(m,12H).

[0145] Example 3

[0146] S1. Add formula II-3 (0.05 mol, 13.1 g) (CAS No.: 51670-87-2), pinacol diboron (0.1 mol, 25.4 g) and potassium acetate (0.125 mol, 12.3 g) into a three-necked flask, 260 ml of 1,4-dioxane as a solvent, replace the nitrogen, and then add (0.5 mmol, 0.46 g) of DBA palladium and (4.0 mmol, 1.9 g) of X-phos under a nitrogen atmosphere, and then react at 100°C for 20 hours, and then obtain formula III-3 (11.0 g, yield 71%) by rotary evaporation and silica gel funnel.

[0147] S2. At room temperature, add formula III-3 (0.05 mol, 15.5 g), formula IV (0.042 mol, 10.8 g) and potassium carbonate (0.125 mol, 17.3 g), 155 ml of tetrahydrofuran, 78 ml of anhydrous ethanol and 78 ml of water as solvents into a three-necked flask, replace the nitrogen, add tetrakis(triphenylphosphine)palladium (1.25 mmol, 1.44 g), and then react at 100°C for 24 hours, and then obtain formula V-3 (9.68 g, yield 64%, HPLC: 99.4%) by separation and column chromatography.

[0148] The synthetic route of Formula I-463 is as follows:

[0149]

[0150] S3. Synthesis of Formula VI-3:

[0151] Formula V-3 (0.03 mol, 10.8 g) was added to a three-necked flask, dissolved in tetrahydrofuran, 1M ethylmagnesium bromide tetrahydrofuran solution (80 ml) was added at low temperature, reacted at room temperature for 8 hours, and then 150 ml of saturated ammonium chloride aqueous solution was added for separation, and the organic phase was extracted twice with brine, and then spin-dried to obtain formula VI-3. 110 ml of acetic acid and 1.1 ml of concentrated sulfuric acid were added to the prepared VI-3, reacted at 90°C for 2.5 hours, and then 110 ml of ethanol and 110 ml of water were added to obtain formula VII-3 (8.1 g, yield 69%).

[0152] S4. Under a nitrogen atmosphere, add formula Ⅶ-3 (0.03 mol, 11.2 g) and iridium trichloride (0.012 mol, 4.3 g) into a three-necked flask, then add 110 ml of ethylene glycol ether, and react at 120°C for 48 hours to obtain formula Ⅷ-3.

[0153] S5. Add formula VIII-3 (0.005 mol, 9.8 g) and anhydrous potassium carbonate (0.05 mol, 6.9 g) into a three-necked flask, 100 ml of ethylene glycol ether as solvent, replace nitrogen, add formula IX-3 (0.015 mol, 3.4 g) (CAS No.: 2412938-98-6), react at 120°C for 48 hours, filter and pass through a silica gel funnel to obtain formula I-463 (7.9 g, yield 69%, HPLC: 99.4%).

[0154] The results of mass spectrometry and elemental analysis of compound formula I-463 are shown below:

[0155] Test value: 1166.97.

[0156] Elemental analysis: calculated values ​​are C:71.91; H:6.21; Ir:16.68; N:2.43; O:2.78; measured values ​​are C:71.28; H:6.46; N:2.63; O:2.33;

[0157] NMR data: 1 H NMR(400MHz,Chloroform-d)δ8.97(d,2H),8.09(dd,2H),8.00–7.94(m,4H),7.79(dd,2H),7.74(dd,2H),7.65(t,2H),7.41–7.27 (m,6H),5.92(d,1H),2.74(tq,1H),1.95(qd,4H),1.68–1.48(m,8H),1.35(s,18H),1.09–1.03(m,9H),0.89(tt,6H),0.82(t,6H).

[0158] Example 4

[0159] The synthetic route of Formula I-816 is as follows:

[0160]

[0161] S1. Add formula II-4 (0.05 mol, 13.9 g) (CAS No.: 161583-93-3), bipyralidin (0.1 mol, 25.4 g) and potassium acetate (0.125 mol, 12.3 g) into a three-necked flask, 320 ml of 1,4-dioxane as solvent, replace nitrogen, and then add (0.5 mmol, 0.46 g) of DBA palladium and (4.0 mmol, 1.9 g) of X-phos under nitrogen atmosphere, and then react at 100 ° C for 20 hours, and then obtain formula III-4 (12.2 g, yield 66%) by rotary evaporation and silica gel funnel.

[0162] S2. At room temperature, add formula III-4 (0.05 mol, 16.3 g), formula IV (0.042 mol, 10.8 g) and potassium carbonate (0.125 mol, 17.3 g), 186 ml of tetrahydrofuran, 93 ml of anhydrous ethanol and 93 ml of water as solvent into a three-necked flask, replace the nitrogen and add tetrakis(triphenylphosphine)palladium (1.25 mmol, 1.44 g), then react at 100°C for 24 hours, and obtain formula V-4 (11.1 g, yield 63%, HPLC: 99.3%) by separation and column chromatography.

[0163] S3. Synthesis of Formula VI-4:

[0164] Formula V-4 (0.03 mol, 11.4 g) was added to a three-necked flask, dissolved in tetrahydrofuran, and 1M phenylmagnesium bromide tetrahydrofuran solution (80 ml) was added at low temperature, reacted at room temperature for 8 hours, and then 150 ml of saturated ammonium chloride aqueous solution was added for separation, and the organic phase was extracted twice with brine, and then spin-dried to obtain formula VI-4. 130 ml of acetic acid and 1.3 ml of concentrated sulfuric acid were added to the prepared VI-4, reacted at 90°C for 2.5 hours, and then 130 ml of ethanol and 130 ml of water were added to obtain formula VII-4 (9.4 g, yield 65%).

[0165] S4. Under a nitrogen atmosphere, add formula Ⅶ-4 (0.03 mol, 13.2 g) and iridium trichloride (0.012 mol, 4.3 g) into a three-necked flask, then add 145 ml of ethylene glycol ether, and react at 120°C for 48 hours to obtain formula Ⅷ-4.

[0166] S5. Add formula VIII-4 (0.005 mol, 16.9 g) and anhydrous potassium carbonate (0.05 mol, 6.9 g) into a three-necked flask, 120 ml of ethylene glycol ether as solvent, replace nitrogen and add formula IX-3 (0.015 mol, 4.0 g) (CAS No.: 1821143-86-5), react at 120°C for 48 hours, filter and pass through a silica gel funnel to obtain formula I-816 (10.1 g, yield 71%, HPLC: 99.3%).

[0167] The results of mass spectrometry and elemental analysis of compound formula I-816 are shown below:

[0168] Test value: 1336.65.

[0169] Elemental analysis: calculated values ​​are C:66.54; H:5.58; Ge:10.19; Ir:13.48; N:1.96; O:2.24; measured values ​​are C:66.31; H:5.14; Ge:10.54; N:1.87; O:2.84;

[0170] NMR data: 1 H NMR(400MHz,Chloroform-d)δ8.99(d,2H),8.29(dd,2H),8.18(s,2H),8.01(d,2H),7.92–7.81(m,4H),7.76(dd,2H),7.35(ddd,4H), 7.35–7.22(m,8H),7.22–7.16(m,4H),5.89(d,1H),2.60(tq,1H),2.43(td,1H),2.11–2.01(m,4H),0.95–0.85(m,24H),0.72(s,18H).

[0171] Example 5

[0172] The synthetic route of Formula I-896 is as follows:

[0173] S1. Add formula II-5 (0.05 mol, 14.1 g) (CAS No.: 59951-65-4), pinacol diboron (0.1 mol, 25.4 g) and potassium acetate (0.125 mol, 12.3 g) into a three-necked flask, 280 ml of 1,4-dioxane as a solvent, replace the nitrogen, and then add (0.5 mmol, 0.46 g) of DBA palladium and (4.0 mmol, 1.9 g) of X-phos under a nitrogen atmosphere, and then react at 100°C for 20 hours, and then obtain formula III-5 (11.1 g, yield 68%) by rotary evaporation and silica gel funnel.

[0174] S2. At room temperature, add formula III-5 (0.05 mol, 16.5 g), formula IV (0.042 mol, 10.8 g) and potassium carbonate (0.125 mol, 17.3 g), 160 ml of tetrahydrofuran, 80 ml of anhydrous ethanol and 80 ml of water as solvents into a three-necked flask, replace the nitrogen, add tetrakis(triphenylphosphine)palladium (1.25 mmol, 1.44 g), and then react at 100°C for 24 hours, and then obtain formula V-5 (9.95 g, yield 63%, HPLC: 99.5%) by separation and column chromatography.

[0175] S3. Synthesis of Formula VI-5:

[0176] Formula V-5 (0.03 mol, 11.5 g) was added to a three-necked flask, dissolved in tetrahydrofuran, 1M ethylmagnesium bromide tetrahydrofuran solution (80 ml) was added at low temperature, reacted at room temperature for 8 hours, and then 150 ml of saturated ammonium chloride aqueous solution was added for separation, and the organic phase was extracted twice with brine, and then spin-dried to obtain formula VI-5. 110 ml of acetic acid and 1.1 ml of concentrated sulfuric acid were added to the prepared VI-5, reacted at 90°C for 2.5 hours, and then 110 ml of ethanol and 110 ml of water were added to obtain formula VII-5 (7.9 g, yield 68%).

[0177]

[0178] S4. Under a nitrogen atmosphere, add formula Ⅶ-5 (0.03 mol, 11.9 g) and iridium trichloride (0.012 mol, 4.3 g) into a three-necked flask, then add 120 ml of ethylene glycol ether, and react at 120°C for 48 hours to obtain formula Ⅷ-5.

[0179] S5. Add formula VIII-5 (0.005 mol, 10.2 g) and anhydrous potassium carbonate (0.05 mol, 6.9 g) into a three-necked flask, 100 ml of ethylene glycol ether as solvent, replace nitrogen, add formula IX-3 (0.015 mol, 5.2 g) (CAS No.: 2960961-69-5), react at 120°C for 48 hours, filter and pass through a silica gel funnel to obtain formula I-896 (9.3 g, yield 71%, HPLC: 99.3%).

[0180] The results of mass spectrometry and elemental analysis of compound formula I-896 are shown below:

[0181] Test value: 1328.74.

[0182] Elemental analysis: calculated values ​​are C:66.39; H:5.88; F:8.63; Ir:14.55; N:2.12; O:2.42; measured values ​​are C:66.51; H:5.54; F:8.42; N:2.96; O:2.57;

[0183] NMR data: 1 H NMR(400MHz,Chloroform-d)δ8.89(d,2H),7.97–7.80(m,8H),7.74(dd,2H),7.67(t,2H),7.41–7.27(m,6H),5.98(d,1H), 2.81(s,2H),2.15(dq,4H),1.95(qd,4H),1.80–1.69(m,2H),1.24(s,3H),1.20(s,18H),1.09–0.99(m,12H),0.82(t,3H).

[0184] Table 1 shows the structure, molecular formula, mass spectrum and yield of the target structural compounds corresponding to Examples 6 to 15:

[0185] Table 1 Related data of Examples 6 to 15

[0186]

[0187]

[0188] Example 16

[0189] In Example 16, an organic electroluminescent device is provided, comprising a substrate, an anode layer, a hole injection layer, a hole transport layer, an organic light emitting layer, an air barrier layer, an electron transport layer, an electron injection layer and a cathode layer. The method for preparing the organic electroluminescent device is as follows:

[0190] (1) ITO anode preparation

[0191] The coating thickness is The ITO glass substrate was cleaned twice in distilled water, cleaned using an ultrasonic device for 35 minutes, and then cleaned twice in distilled water and ultrasonically cleaned for 15 minutes. After cleaning, it was ultrasonically cleaned in turn using isopropyl alcohol, acetone, methanol and other solvents, then dried, and then transferred to a plasma cleaner for washing for 5 minutes, and then sent to a vapor deposition machine for vapor deposition of other functional layers.

[0192] (2) Hole injection layer and hole transport layer

[0193] by The evaporation rate of formula Ⅰ-A and formula Ⅰ-B are vacuum evaporated into the hole injection layer, and the evaporation rate ratio is 95:5. The chemical formula of formula Ⅰ-A / B is shown below. At a deposition rate of , 120 nm of Formula Ⅰ-A was evaporated on the hole injection layer as a hole transport.

[0194]

[0195]

[0196] (3) Organic light-emitting layer

[0197] by The evaporation rate is 28 nm, and a luminescent layer is evaporated with 4,4'-N,N'-biphenyldicarbazole ("CBP") as the main material and formula I-1 as the doping material, wherein the weight ratio of CBP to compound formula I-1 is 95:5.

[0198] (4) Hole blocking layer

[0199] by The hole blocking layer with a thickness of 5.0 nm was formed by vacuum evaporation of the compound of formula Ⅰ-C at an evaporation rate of .

[0200]

[0201] (5) Electron transport layer, electron injection layer

[0202] by The deposition rate is 35 nm, and the electron transport layer of "Alq3" is vacuum-deposited. The evaporation rate is 0.5nm, and the electron injection layer of LiF film is vacuum evaporated.

[0203] (6) Cathode layer

[0204] by The evaporation rate ratio is 15nm, and 15nm of silver is evaporated to obtain an organic electroluminescent device.

[0205] Referring to Example 16, the doping material formula Ⅰ-1 in the organic electroluminescent device is replaced by formula Ⅰ-2, Ⅰ-15, Ⅰ-90, Ⅰ-215, Ⅰ-251, Ⅰ-307, Ⅰ-364, Ⅰ-463, Ⅰ-490, Ⅰ-532, Ⅰ-583, Ⅰ-652, Ⅰ-816, and Ⅰ-896, and they are prepared into relevant organic electroluminescent devices respectively.

[0206] Comparative Example 1

[0207] An organic electroluminescent device is prepared using the preparation method of Example 16, and the doping material of Formula Ⅰ-1 in its light-emitting layer is replaced by a compound of Formula Ⅰ-D. The structure of Formula Ⅰ-D is shown below.

[0208]

[0209] Comparative Example 2

[0210] An organic electroluminescent device is prepared using the preparation method of Example 16, and the doping material of Formula Ⅰ-1 in its light-emitting layer is replaced by a compound of Formula Ⅰ-E. The structure of Formula Ⅰ-E is shown below.

[0211]

[0212] In order to further illustrate the luminescent properties of the new red-light metal complex material provided by the present invention, the luminescent characteristics of the organic light-emitting device prepared in Example 16 and the device obtained in Comparative Example 1 were tested. The measurement was carried out using a KEITHLEY 2400 source measurement unit and a CS-2000 spectroradiometer to evaluate the driving voltage, luminescent brightness, and luminescent efficiency. The results are shown in Table 2.

[0213] Table 2 Luminescence detection data of organic electroluminescent devices of Example 16 and Comparative Example 1

[0214]

[0215]

[0216] Compared with the structures in Examples 1 and 2, Formulas I-D and I-E in Comparative Examples 1 and 2 have the same 2-phenylpyridine structure, but the structures of the 2-phenylpyridine derivatives in Examples 1 and 2 have more six-membered rings and benzene ring structures, which can adjust the wavelength of the metal complex material, so that the compound has better luminescent properties, and the device has better driving voltage, brightness and service life. These advantages can be found in Table 2. When the brightness is the same as 8000, compared with Comparative Examples 1 and 2 doped with Formulas I-D and I-E, the device provided by the present invention has a relatively low driving voltage, and the efficiency and life are also improved. It can be seen that the organic electroluminescent device prepared by using the compound provided by the present invention as the doping material of the light-emitting layer has better luminous efficiency and a longer service life.

[0217] It will be apparent to those skilled in the art that many modifications and variations of the present invention are possible without departing from the spirit and scope of the present invention. It is therefore contemplated that the present invention covers modifications and variations of the present invention provided within the scope of the appended claims and their equivalents.

[0218] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A phosphorescent doped material, characterized in that: It has the structure shown in general formula I: wherein R1 to R8 each independently represent hydrogen, a deuterium atom, a halogen, a hydroxyl group, a cyano group, a nitro group, an amino group, a sulfonic acid group, a substituted or unsubstituted C1-C 50 Alkyl, substituted or unsubstituted C6-C 50 Aryl, substituted or unsubstituted C6-C 50 Heteroaryl, substituted or unsubstituted C3-C 50 Cycloalkyl, substituted or unsubstituted C1-C 50 Alkoxy, substituted or unsubstituted C1-C 50 Alkylamino, substituted or unsubstituted C2-C 50 Alkenyl or alkyne, substituted or unsubstituted C4-C 50 Heterocyclyl, substituted or unsubstituted C 10 -C 50 Condensed ring group, substituted or unsubstituted C5-C 50 Spirocyclyl, substituted or unsubstituted C1-C 50 Silane, substituted or unsubstituted C1-C 50 The germanium alkyl group, the substituents at the positions of R1 to R8 are the same or different. The positions of R1 to R4 are fixed; the positions of R5 to R8 are any positions of the benzene ring, and the number of the substituents of R5 to R8 is 0 to 4.

2. The phosphorescent doping material according to claim 1, characterized in that: The R1 to R3 are each independently selected from hydrogen and the following groups: in Represents the connection location.

3. The phosphorescent doping material according to claim 1, characterized in that: The R5-R8 each independently represents hydrogen, deuterium, cyano, fluorine, trimethylsilyl, trimethylgermanyl, substituted or unsubstituted C1-C 15 Alkyl, substituted or unsubstituted C3-C 15 Cycloalkyl, substituted or unsubstituted C3-C 15 Alkoxy, substituted or unsubstituted C4-C 15 Heterocyclic, substituted or unsubstituted C6-C 15 Aryl, substituted or unsubstituted C 10 -C 20 The fused ring group, R5 to R8 are the same or different.

4. The phosphorescent doping material according to claim 3, characterized in that: The substituted or unsubstituted C1-C 15 The alkyl group is any one of methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, isobutyl, pentyl, isopentyl, neopentyl, hexyl, 2-methylpentyl, 3-methylpentyl, 2,3-dimethylbutyl and 2,2-dimethylbutyl; The substituted or unsubstituted C6-C 15 The aryl group is any one of phenyl, tolyl, chlorophenyl, bromophenyl, fluorophenyl, biphenyl, terphenyl, naphthyl, anthracenyl, and phenanthryl. The substituted or unsubstituted C1-C 15 The cycloalkyl group includes any one of cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and cyclooctyl. The substituted or unsubstituted C1-C 15 The alkoxy group includes any one of a methoxy group, an ethoxy group, a propoxy group, and a phenoxy group. The substituted or unsubstituted C1-C 15 The heterocyclic group includes an aromatic or non-aromatic cyclic group containing at least one heteroatom, wherein the heteroatom is selected from one or more combinations of O, S, N, P, B, Si and Ge.

5. The phosphorescent doping material according to claim 1, characterized in that: The R1 to R8 can be arbitrarily combined to form a substituted or unsubstituted condensed ring, and the substituents that do not form a condensed ring include hydrogen, deuterium, cyano, substituted or unsubstituted C1-C 50 Alkyl, substituted or unsubstituted C1-C 50 Aryl, substituted or unsubstituted C3-C 15 Cycloalkyl, substituted or unsubstituted C4-C 50 Heterocyclic, substituted or unsubstituted C 10 -C 20 A fused ring group, a substituted or unsubstituted C5-C 50 The spirocyclic group may or may not contain any one or more of O, S, N, P, B, Si and Ge in the formed condensed ring.

6. The phosphorescent doping material according to claim 5, characterized in that: The hydrogen atoms in the groups or substituent groups of R1 to R8 can all be replaced by deuterium.

7. The phosphorescent doping material according to claim 1, characterized in that: The phosphorescent doping material is selected from any one of the compounds shown in the following structural formulas:

8. The method for preparing the phosphorescent doping material according to claim 1, characterized in that: The method specifically comprises the following steps: S1. Add a compound of formula II (1.0 eq), bipyralidin and potassium acetate (2.0-3.0 eq) into a three-necked flask, and use 1,4-dioxane (15.0-25.0 eq) as a solvent, replace the nitrogen, and then add a catalyst under a nitrogen atmosphere. After reacting for a period of time at 90°C to 110°C, obtain a compound of formula III by rotary evaporation and passing through a silica gel funnel. S2. At room temperature, a compound of formula III (1.0-1.5 eq), a compound of formula IV (1.0 eq), potassium carbonate (2.0-4.0 eq), tetrahydrofuran (8.0-12.0 eq), anhydrous ethanol and water as solvents are added into a three-necked flask, and after replacing the nitrogen, tetrakis(triphenylphosphine)palladium (0.02-0.04 eq) is added, and then the temperature is raised to 70°C to 100°C, and the reaction is carried out for 12h to 24h, and then the compound of formula V is obtained by separation and column chromatography. S3. Synthesis of compounds of formula VI: ① Add the compound of formula V into a high-pressure reactor, add a solvent to replace nitrogen twice, add a metal-based catalyst, and then replace nitrogen twice. At a temperature of 80°C to 120°C and a reaction pressure of 4 to 6 MPa, introduce hydrogen to react for a period of time to obtain a product compound of formula VI. Add acetic acid (10.0-15.0 eq) and concentrated sulfuric acid (0.05 eq-0.225 eq) to the obtained compound of formula VI (1.0 eq), react at a temperature of 85°C to 100°C for 1.5 h to 2.5 h, and add ethanol and water to obtain a compound of formula VII. ② Under a nitrogen atmosphere, the compound of formula V is dissolved in a tetrahydrofuran solvent, a Grignard reagent solution is added at a low temperature of 0°C, and the reaction is carried out at room temperature for 4 to 8 hours to obtain a compound of formula VI; then acetic acid (10.0-15.0eq) and concentrated sulfuric acid (0.05eq-0.225eq) are added to the obtained compound of formula VI (1.0eq), and the reaction is carried out at a temperature of 85°C to 100°C for 1.5h to 2.5h, and ethanol and water are added thereto to obtain a compound of formula VII. S4. Under a nitrogen atmosphere, add the compound of formula VII (2.0-3.0 eq) and iridium trichloride (1.0 eq) into a three-necked flask, and react at 120°C for 24 h to 48 h to obtain the compound of formula VIII. S5. Add a compound of formula VIII (1.0 eq) and anhydrous potassium carbonate into a three-necked flask, use ethylene glycol ethyl ether as a solvent, replace the nitrogen, then add a compound of formula IX (2.0-3.5 eq), react at 120°C for 24-48 hours, filter and pass through a silica gel funnel to obtain a compound of formula I. The specific synthetic route is as follows: wherein X is selected from fluorine, chlorine and bromine.

9. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises an organic layer; the organic layer contains the phosphorescent doping material as claimed in claim 1.

10. The organic electroluminescent device according to claim 9, characterized in that: The organic electroluminescent device further comprises a first electrode and a second electrode; the organic layer is disposed between the first electrode and the second electrode; wherein, The organic layer includes at least one of a hole injection layer, a hole transport layer, an electron blocking layer, a luminescence auxiliary layer, a luminescent layer, a hole blocking layer, an electron transport layer and an electron injection layer; the luminescent layer contains the phosphorescent doping material.

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