Tetradentate cyclometalated platinum (II) complex based on pyridylcarbazole and application thereof, and electronic device,

Abstract

The present invention belongs to the field of organic electroluminescence, and specifically relates to a tetradentate cyclometalated platinum (II) complex based on pyridylcarbazole and an application thereof, and an electronic device. In the present invention, a charge distribution in an excited state of a compound is improved by means of introducing a substituent group at an appropriate position of a ligand of the compound, such that there are more metal-to-pyridocarbene charge transfer states (3MLCT) in an excited state of a material composed of the compound, which is conductive to improving a radiation rate, thereby extending the service life of a device. The material provided has good chemical stability and thermal stability, and is easily prepared into evaporated OLED devices. An organic electroluminescent device manufactured by using the compound of the present invention as a light-emitting layer has significantly improved current efficiency and service life and a significantly reduced turn-on voltage. After the compound is combined with a fluorescent doped material (a boron-containing compound), transmissions of holes and electrons can be balanced, such that energy transfer between a host and a guest is more efficient, and the light color purity of a device can be improved.

Description

A pyridylcarbazole-based tetradentate ring metal platinum (II) complex, electronic device and application thereof Technical Field

[0001] The present invention belongs to the field of organic electroluminescence, and in particular relates to a pyridylcarbazole-based tetradentate ring metal platinum (II) complex, an electronic device and applications thereof. Background Art

[0002] Organic light-emitting diodes (OLEDs) are a new generation of full-color display and lighting technology. Compared to liquid crystal displays, which have shortcomings such as slow response speed, small viewing angle, need for backlight, and high energy consumption, OLED, as an autonomous light-emitting device, does not require a backlight and is energy-efficient. It also has low driving voltage, fast response speed, high resolution and contrast, wide viewing angle, and outstanding low-temperature performance. OLED devices can be made thinner and can be made into flexible structures. In addition, it has the advantages of low production cost, simple production process, and large-scale production. Therefore, OLED has broad and huge application prospects in high-end electronic products and aerospace. With the gradual increase in investment, further in-depth research and development, and the upgrading and transformation of production equipment, OLEDs will have very broad application scenarios and development prospects in the future.

[0003] The core of OLED development lies in the design and development of luminescent materials. The luminescent layers of currently used OLED devices almost all utilize a host-guest luminescence mechanism. This involves doping a guest luminescent material into a host material. The host material generally has a higher energy system than the guest luminescent material. Energy is transferred from the host material to the guest material, exciting the guest material to emit light. Commonly used organic phosphorescent guest materials are heavy metal atoms such as iridium(III), platinum(II), and palladium(II). Commonly used phosphorescent organic materials, mCBP (3,3′-bis(9-carbazolyl)-biphenyl) and 2,6-mCPy (2,6-bis(9-carbazolyl)-pyridine), possess high efficiency and high triplet energy levels. When used as organic materials, triplet energy can be efficiently transferred from the luminescent organic material to the guest phosphorescent luminescent material. However, due to the easy hole transport properties of mCBP and the poor hole transport properties of 2,6-mCPy, the charge imbalance in the luminescent layer reduces the current efficiency of the device. In addition, the number of heavy metal phosphorescent organic complex molecules and cyclometallated iridium (III) complex molecules currently in use is limited. The content of metallic platinum in the earth's crust and the annual production worldwide are both about ten times that of metallic iridium. IrCl3 used to prepare iridium (III) complex phosphorescent materials .The price of H2O is also much higher than PtCl2 used to prepare platinum (II) complex phosphorescent materials. In addition, the preparation of iridium (III) complex phosphorescent materials involves four steps: iridium (III) dimer, iridium (III) intermediate ligand exchange, synthesis of mer-iridium (III) complex and conversion of mer- to fac-iridium (III) complex isomers, which greatly reduces the overall yield and the cost of raw material IrCl3. . The increased utilization of H₂O increases the preparation cost of iridium (III) complex phosphorescent materials. In contrast, the preparation of platinum (II) complex phosphorescent materials only involves the final step of metallization of the ligand and the design of the platinum salt reaction. This high utilization of the platinum element can further reduce the preparation cost of platinum (II) complex phosphorescent materials. In summary, the preparation cost of platinum (II) complex phosphorescent materials is much lower than that of iridium (III) complex phosphorescent materials. However, the development of platinum complex materials and devices still faces several technical difficulties. Improving device efficiency and lifespan is a relatively important research issue. Therefore, the development of new phosphorescent metal platinum (II) complexes is urgently needed.

[0004] Summary of the Invention

[0005] In light of this, the present invention aims to provide a pyridylcarbazole-based tetradentate metal platinum (II) complex, an electronic device, and its applications. The pyridylcarbazole-based tetradentate metal platinum (II) complex of the present invention, when used as a guest phosphorescent material in the light-emitting layer, can impart excellent device performance. This can improve the current efficiency and device life of organic electroluminescent devices, while also reducing the operating voltage of the device.

[0006] In order to achieve the above technical objectives, the technical solutions of the present invention are as follows:

[0007] The present invention provides a pyridylcarbazole-based tetradentate metal platinum (II) complex, wherein the complex has a structure as shown in formula (I):

[0008] In formula (I), R 1 -R 6 Each independently represents a single substitution to the maximum number of substitutions, or no substitution; R 1 -R 6 Each is independently selected from the group consisting of hydrogen, deuterium, halogen, C1-C30 alkyl, C1-C30 haloalkyl, substituted or unsubstituted C6-C60 aryl, and combinations thereof;

[0009] R a 、R b Each is independently selected from the group consisting of: hydrogen, deuterium, C1-C30 alkyl, substituted or unsubstituted C6-C60 aryl, and combinations thereof; the substitution is deuterium, C1-C30 alkyl, C6-C60 aryl.

[0010] Furthermore, R a is selected from hydrogen, deuterium, C₂O₃, C₁–C₁₀ alkyl, C₆–C₃₀ aryl, and combinations thereof; R b Selected from hydrogen, deuterium, C1-C20 alkyl and combinations thereof.

[0011] Furthermore, R 1 -R 6 Each is independently selected from hydrogen, deuterium, CD3, F, CF3, methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, pentyl, hexyl, heptyl, phenyl, and combinations thereof.

[0012] Preferably, the pyridylcarbazole-based tetradentate metal platinum (II) complex is selected from any one of the chemical structures shown below, wherein "D" represents deuterium:

[0013] Furthermore, the present invention also provides the use of the tetradentate ring metal platinum (II) complex having the structure shown in formula (I) in electronic devices.

[0014] Furthermore, the electronic devices include organic electroluminescent devices (OLEDs), organic integrated circuits (O-ICs), organic field effect transistors (O-FETs), organic thin film transistors (O-TFTs), organic light emitting transistors (O-LETs), organic solar cells (O-SCs), organic optical detectors, organic photoreceptors, organic field quenching devices (O-FQDs), light emitting electrochemical cells (LECs) and organic laser diodes (O-lasers).

[0015] In another aspect, the present invention further provides an organic electroluminescent device, which comprises the tetradentate ring metal platinum (II) complex having a structure represented by formula (I) as described above.

[0016] Furthermore, the organic electroluminescent device comprises a cathode, an anode and an organic functional layer therebetween; the organic functional layer comprises the tetradentate ring metal platinum (II) complex having the structure shown in formula (I) as described above.

[0017] Preferably, the organic functional layer comprises a light-emitting layer, and the light-emitting layer comprises the tetradentate ring metal platinum (II) complex having the structure represented by formula (I) as described above.

[0018] Furthermore, the light-emitting layer further comprises a fluorescent doping material; the fluorescent doping material is a boron-containing organic molecular light-emitting compound.

[0019] In another aspect, the present invention further provides an organic optoelectronic device comprising: a substrate layer; a first electrode on the substrate; an organic light-emitting functional layer on the first electrode; and a second electrode on the organic light-emitting functional layer. The organic light-emitting functional layer comprises a tetradentate ring metal platinum (II) complex having a structure represented by formula (I). For example, the platinum (II) complex can be included in the organic light-emitting functional layer as a luminescent material.

[0020] Furthermore, the organic light-emitting functional layer further comprises any one or more fluorescent doping materials.

[0021] The present invention also provides a composition comprising a tetradentate ring metal platinum (II) complex having a structure represented by formula (I) as described above. Preferably, the composition further comprises a fluorescent dopant material, wherein the fluorescent dopant material is preferably a phosphorescent sensitized boron-containing compound.

[0022] The present invention also provides a preparation comprising the tetradentate ring metal platinum (II) complex having a structure represented by formula (I) or the composition described above and at least one solvent.

[0023] The solvent is not particularly limited and may be used, for example, unsaturated hydrocarbon solvents such as toluene, xylene, mesitylene, tetralin, decalin, bicyclohexane, n-butylbenzene, sec-butylbenzene, tert-butylbenzene, carbon tetrachloride, chloroform, dichloromethane, dichloroethane, chlorobutane, bromobutane, chloropentane, bromopentane, hexyl chloride, bromohexane, chlorocyclohexane, bromocyclohexane, halogenated unsaturated hydrocarbon solvents such as chlorobenzene, dichlorobenzene, trichlorobenzene, ether solvents such as tetrahydrofuran and tetrahydropyran, and ester solvents such as alkyl benzoate.

[0024] The present invention also provides a display or lighting device, which comprises one or more of the organic photoelectric devices described above.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The present invention improves the charge distribution of the excited state of the compound by introducing a substituent group at an appropriate position of the ligand, so that the excited state of the material has more metal to pyridocarbene charge transfer states ( 3The materials provided have excellent chemical and thermal stability, making them easy to prepare vapor-deposited OLED devices. Organic electroluminescent devices fabricated using the compounds of the present invention as the light-emitting layer exhibit significant improvements in current efficiency and lifespan, while significantly reducing the turn-on voltage. Combining them with fluorescent doping materials (boron-containing compounds) balances the transport of holes and electrons, making energy transfer between the host and guest more efficient and improving the device's light color purity. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is the room temperature emission spectra of Pt-1 to Pt-4 in dichloromethane solution. DETAILED DESCRIPTION

[0028] The following describes the present invention in detail. The description of the components described below may be based on representative embodiments or specific examples of the present invention, but the present invention is not limited to such embodiments or specific examples.

[0029] The term "substituted" as used herein is intended to include all permissible substituents of organic compounds. In a broad sense, permissible substituents include acyclic and cyclic, branched and unbranched, carbocyclic and heterocyclic, and aromatic and non-aromatic substituents of organic compounds. Illustrative substituents include, for example, those described below. For suitable organic compounds, permissible substituents may be one or more, identical or different. For the purposes of the present invention, the present invention is not intended to impose any restrictions in any way on the permissible substituents of organic compounds. Similarly, the terms "substituted" or "substituted with" include the implicit condition that such substitution conforms to the permissible valence of the substituted atom and the substituent, and that the substitution results in a stable compound (e.g., a compound that does not spontaneously undergo transformation (e.g., by rearrangement, cyclization, elimination, etc.)). It is also contemplated that, in certain aspects, unless explicitly stated otherwise, a single substituent can further optionally be substituted (i.e., further substituted or unsubstituted).

[0030] In defining various terms, “R 1 ”-“R 6 " are used as general symbols in the present invention to represent various specific substituents. These symbols can be any substituents, not limited to those disclosed in the present invention, and when they are limited to certain substituents in one case, they can be limited to some other substituents in other cases. The "R" used in the present invention 1 ”, “R 2 ”…“R n ”(wherein n is an integer) may independently have one or more of the groups listed above. For example, if R 1If it is a straight chain alkyl group, then one of the hydrogen atoms of the alkyl group may be optionally substituted with a hydroxyl group, an alkoxy group, an alkyl group, a halogen, etc. Depending on the groups selected, the first group may be incorporated within the second group, or alternatively, the first group may be pendant, ie, attached to the second group.

[0031] The term "alkyl" as used herein refers to a saturated hydrocarbon group of 1 to 60 carbon atoms, which is branched or unbranched, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, tetradecyl, hexadecyl, eicosyl, tetracosyl, etc. The alkyl group may be cyclic or acyclic. The alkyl group may be branched or unbranched. The alkyl group may also be substituted or unsubstituted. For example, the alkyl group may be substituted with one or more groups, including but not limited to the optionally substituted alkyl, cycloalkyl, alkoxy, amino, halogen, hydroxyl, nitro, silyl, sulfo-oxo or sulfhydryl groups of the present invention.

[0032] The term "aryl" used in the present invention is a group containing any carbon-based aromatic group of 5 to 60 carbon atoms, and the carbon-based aromatic group includes but is not limited to phenyl, naphthyl, phenyl, biphenyl, phenoxyphenyl, anthracenyl, phenanthrenyl, etc. The term "aryl" also includes "heteroaryl", which is defined as a group containing an aromatic group, and the aromatic group has at least one heteroatom introduced into the ring of the aromatic group. Examples of heteroatoms include but are not limited to nitrogen, oxygen, sulfur, and phosphorus. Similarly, the term "non-heteroaryl" (which is also included in the term "aryl") defines a group containing an aromatic group, and the aromatic group does not contain heteroatoms. Aryl can be substituted or unsubstituted. The aryl group may be substituted with one or more groups including, but not limited to, alkyl, cycloalkyl, alkoxy, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl, heteroaryl, aldehyde, amino, carboxyl, ester, halogen, hydroxyl, carbonyl, azido, nitro, silyl, sulfo-oxo, or mercapto groups as described herein.

[0033] The compounds of the present invention may contain "optionally substituted" parts. Typically, the term "substituted" (whether or not the term "optionally" is present in the preceding) means that one or more hydrogens of the part indicated are replaced by a suitable substituent. Unless otherwise stated, "optionally substituted" groups may have a suitable substituent at each substitutable position of the group, and when more than one position may be substituted with more than one substituent selected from a specified group in any given structure, the substituent at each position may be the same or different. The substituent combinations envisioned by the present invention are preferably those that form stable or chemically feasible compounds. In some aspects, unless clearly indicated otherwise, it is also contemplated that each substituent may further be optionally substituted (that is, further substituted or unsubstituted).

[0034] The compounds disclosed herein can exhibit desirable properties and have emission and / or absorption spectra that can be tuned by selecting appropriate ligands. In another aspect, the invention can exclude any one or more compounds, structures, or portions thereof specifically recited herein.

[0035] The compounds of the present invention can be prepared using a variety of methods, including but not limited to those described in the examples provided herein.

[0036] It should be noted that the above general description and the following detailed description are only exemplary and explanatory and are not limiting. The present application can be more easily understood by referring to the following specific embodiments and the examples contained therein.

[0037] Before disclosing and describing the compounds, devices and / or methods of the present invention, it should be understood that they are not limited to specific synthetic methods (otherwise otherwise indicated), or specific reagents (otherwise otherwise indicated), as these can of course vary. It should also be understood that the terms used in the present invention are only for the purpose of describing specific aspects and are not intended to be limiting. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing, exemplary methods and materials are described below. All raw materials and solvents in the synthetic examples were purchased commercially unless otherwise specified, and the solvents were used directly without further processing.

[0038] The substrate described in the present invention can be any substrate typically used in organic optoelectronic devices. It can be glass or transparent plastic, or an opaque material such as silicon or stainless steel, or a flexible PI film. Different substrates have varying mechanical strength, thermal stability, transparency, surface smoothness, and water resistance, and their applications vary depending on the properties of the substrate. The materials used in the hole injection layer, hole transport layer, and electron injection layer can be any material from among those known to be used in OLED devices, and the present invention does not impose any specific limitations thereon.

[0039] Synthesis Example

[0040] The following examples of compound syntheses, compositions, devices, or methods are intended only to provide a general approach to the industry and are not intended to limit the scope of protection of this patent. While the data (quantities, temperatures, etc.) mentioned in the patent are as accurate as possible, some errors may occur. Unless otherwise noted, all weights are weighed separately, temperatures are in degrees Celsius or at room temperature, and pressures are near atmospheric pressure.

[0041] The following examples provide methods for preparing novel compounds, but the preparation of such compounds is not limited to these methods. In this area of ​​expertise, since the compounds protected herein are easily modified and prepared, they can be prepared using the methods listed below or other methods. The following examples are provided as examples only and are not intended to limit the scope of protection of this patent. Temperature, catalyst, concentration, reactants, and reaction process can all be varied to select different conditions for preparing the compounds for different reactants.

[0042] 1 H NMR spectra (500 MHz) were measured on an ANANCE III (500M) nuclear magnetic resonance spectrometer. Unless otherwise specified, DMSO-d6 or CDCl3 containing 0.1% TMS was used as the solvent for NMR. 1 When CDCl3 was used as the solvent, TMS (δ = 0.00 ppm) was used as the internal standard for H NMR spectra. When DMSO-d6 was used as the solvent, TMS (δ = 0.00 ppm), the residual DMSO peak (δ = 2.50 ppm), or the residual water peak (δ = 3.33 ppm) was used as the internal standard. 13 In C NMR spectra, CDCl3 (δ = 77.00 ppm) or DMSO-d6 (δ = 39.52 ppm) was used as the internal standard. HPLC-MS was measured on an Agilent 6210 TOF LC / MS mass spectrometer; HRMS spectra were measured on an Agilent 6210 TOF LC / MS liquid chromatography-time-of-flight mass spectrometer. 1 In H NMR spectrum data: s = singlet, d = doublet, t = triplet, q = quartet, p = quintet, m = multiplet, br = broad.

[0043] Synthesis of intermediate A-1-OH

[0044] The synthetic route of intermediate A-1-OH is as follows:

[0045] (1) 1a (1 g, 4.27 mmol, 1.2 equiv), 1b (666 mg, 3.56 mmol, 1.0 equiv), tetrakistriphenylphosphine palladium (82 mg, 0.07 mmol, 2 mol%), and potassium carbonate (984 mg, 7.12 mmol, 2.0 equiv) were added to a three-necked reaction flask equipped with a magnetic rod. The nitrogen atmosphere was then evacuated three times, and ethylene glycol dimethyl ether (6 mL) and water (6 mL) were added under a nitrogen atmosphere. The mixture was heated to 100°C and reacted for 36 hours, then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by column chromatography on silica gel using a 10:1 eluent of dichloromethane / ethyl acetate to obtain 994 mg of a yellow solid, designated A-1-NH2, with a yield of 88%.

[0046] (2) A-1-NH2 (994 mg, 3.35 mmol, 1.0 equivalent) and triethylbenzylammonium chloride (4.38 g, 19.22 mmol, 4.5 equivalent) were added to a three-necked reaction flask equipped with a magnetic rod. The nitrogen atmosphere was then evacuated three times, and tert-butyl nitrite (2.2 g, 21.35 mmol, 5.0 equivalent) and dichloromethane (10 mL) were added under a nitrogen atmosphere. The reaction was stirred in the dark at room temperature for 36 hours, and the solvent was removed by vacuum distillation. The crude product was separated by column chromatography using silica gel with an eluent of dichloromethane / ethyl acetate = 10:1 to obtain 670 mg of a yellow oil, designated as A-1-Cl, with a yield of 55%.

[0047] (3) A-1-Cl (7 g, 22.16 mmol, 1.0 equivalent), 1c (6.56 g, 33.24 mmol, 1.5 equivalent), tris(dibenzylideneacetone)dipalladium (201 mg, 0.22 mmol, 1 mol%), 2-dicyclohexylphosphino-2,4,6-triisopropylbiphenyl (183 mg, 0.44 mmol, 2 mol%), and sodium tert-butoxide (4.3 g, 44.32 mmol, 2.0 equivalent) were added to a three-necked reaction flask equipped with a magnetic rod. The nitrogen atmosphere was then evacuated three times, and toluene (200 mL) was added under a nitrogen atmosphere. The mixture was heated to 110°C for 24 hours and then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by silica gel column chromatography using petroleum ether / ethyl acetate = 20:1 as the eluent to obtain 10.12 g of a gray solid, designated A-1-MOe, with a yield of 96%.

[0048] (4) A-1-MOe (10.12 g, 21.23 mmol, 1.0 equivalent) and 48% hydrobromic acid (50 mL, 212.3 mmol, 10 equivalents) were added to a single-necked reaction flask equipped with a magnetic rod. The mixture was heated to 120°C for 24 hours and then cooled to room temperature. The pH was adjusted to 7-8 with saturated sodium bicarbonate solution. The organic phase was extracted three times with dichloromethane. The combined organic phases were distilled under reduced pressure to remove the solvent. The crude product was slurried with ethyl acetate / petroleum ether to obtain 9.5 g of a white solid, designated as A-1-OH, with a yield of 97%.

[0049] Synthesis of intermediate B-1-OH

[0050] The synthetic route of intermediate B-1-OH is as follows:

[0051] (1) 1d (4 g, 28.56 mmol, 1.2 eq.), 1b (4.45 g, 23.8 mmol, 1.0 eq.), tetrakistriphenylphosphine palladium (496 mg, 0.44 mmol, 2 mol%), and potassium carbonate (6.58 g, 47.6 mmol, 2.0 eq.) were added to a three-necked reaction flask equipped with a magnetic rod. The nitrogen atmosphere was then evacuated three times, and ethylene glycol dimethyl ether (16 mL) and water (16 mL) were added under a nitrogen atmosphere. The mixture was heated to 100°C and reacted for 36 hours, then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by column chromatography on silica gel using a 10:1 eluent of dichloromethane / ethyl acetate to obtain 4.71 g of a yellow solid, designated as B-1-NH2, with a yield of 98%.

[0052] (2) Add B-1-NH2 (4.82 g, 23.82 mmol, 1.0 equivalent) and triethylbenzylammonium chloride (24.43 g, 107.11 mmol, 4.5 equivalent) to a three-necked reaction flask equipped with a magnetic rod. Then, the nitrogen atmosphere was replaced three times. Under a nitrogen atmosphere, tert-butyl nitrite (12.27 g, 199 mmol, 5.0 equivalent) and dichloromethane (80 mL) were added. The reaction was stirred in the dark at room temperature for 36 hours, and then the solvent was removed by vacuum distillation. The crude product was separated by column chromatography using silica gel with an eluent of dichloromethane / ethyl acetate = 10:1 to obtain 4.74 g of a red oil, designated as B-1-Cl, with a yield of 90%.

[0053] (3) Add B-1-Cl (3 g, 14 mmol, 1.0 equiv), 1c (4.14 g, 21 mmol, 1.5 equiv), tris(dibenzylideneacetone)dipalladium (128 mg, 0.14 mmol, 1 mol%), 2-dicyclohexylphosphino-2,4,6-triisopropylbiphenyl (166 mg, 0.28 mmol, 2 mol%), and sodium tert-butoxide (2.69 g, 28 mmol, 2.0 equiv) to a three-necked reaction flask equipped with a magnetic rod. The nitrogen atmosphere was then evacuated three times, and toluene (60 mL) was added under a nitrogen atmosphere. The mixture was heated to 110°C for 24 hours and then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by silica gel column chromatography using petroleum ether / ethyl acetate = 20:1 as the eluent to obtain 3.3 g of a gray solid with a yield of 62%.

[0054] Synthesis of intermediate A-2-Cl

[0055] The synthetic route of intermediate A-2-Cl is as follows:

[0056] (1) Potassium phosphate (9.2 g, 4.32 mmol, 2.0 equiv) was added to a three-necked reaction flask with a magnetic rod. The water was removed with a heat gun under vacuum, and then A-1-OH (1 g, 2.16 mmol, 1.0 equiv), 2-pyridinecarboxylic acid (53 mg, 0.43 mmol, 20 mol%), and cuprous iodide (82 mg, 0.43 mmol, 20 mol%) were added. The nitrogen atmosphere was then evacuated three times, and 1d (830 mg, 4.32 mmol, 2.0 equiv) and dimethyl sulfoxide (20 mL) were added under nitrogen atmosphere. The mixture was heated to 90°C for 36 hours and then cooled to room temperature. Deionized water was added to quench the mixture, and the organic phase was extracted three times with ethyl acetate. The organic phases were combined and the solvent was removed by distillation under reduced pressure. The crude product was separated by column chromatography on silica gel with an eluent of ethyl acetate / petroleum ether = 40:1 to obtain 450 mg of a yellow oil with a yield of 36%.

[0057] Synthesis of intermediate A-3-Cl

[0058] The synthetic route of intermediate A-3-Cl is as follows:

[0059] (1) Potassium phosphate (8.8 g, 20.72 mmol, 2.0 equiv) was added to a three-necked reaction flask equipped with a magnetic rod. The water was removed with a heat gun under vacuum. A-1-OH (9.59 g, 20.72 mmol, 1.0 equiv), 2-pyridinecarboxylic acid (510 mg, 4.14 mmol, 20 mol%), and cuprous iodide (788 mg, 4.14 mmol, 20 mol%) were then added. The nitrogen atmosphere was then purged three times. 1f (11.38 g, 41.44 mmol, 2.0 equiv) and dimethyl sulfoxide (100 mL) were then added under nitrogen atmosphere. The reaction mixture was heated to 90°C for 12 hours and then cooled to room temperature. Deionized water was added to quench the mixture. The organic phase was extracted three times with ethyl acetate. The organic phases were combined and the solvent was removed by distillation under reduced pressure. The crude product was separated by column chromatography on silica gel with an eluent of ethyl acetate / petroleum ether = 50:1 to obtain 9.89 g of a yellow oil, designated as A-3-Cl, with a yield of 76%. 1 H NMR(500MHz,Chloroform-d)δ8.54(s,1H),8.09(dd,J=10,5Hz,2H),7.84(d,J=10Hz,1H),7.58(d,J=5Hz,1H),7.52–7.48(m,2H),7.47–7.42(m,1 H),7.35–7.30(m,1H),7.25(d,J=10Hz,2H),7.06(t,J=5Hz,1H),7.04–6 .99(m,2H),6.78(t,J=5Hz,1H),2.42(s,3H),1.39(s,18H),1.28(s,9H).

[0060] Synthesis of intermediate A-4-Cl

[0061] The synthetic route of intermediate A-4-Cl is as follows:

[0062] (1) Potassium phosphate (1.27 g, 6 mmol, 2.0 equiv) was added to a three-necked reaction flask with a magnetic rod. The water was removed with a heat gun under vacuum, and then B-1-OH (1 g, 3 mmol, 1.0 equiv), 2-pyridinecarboxylic acid (37 mg, 0.3 mmol, 20 mol%), and cuprous iodide (57 mg, 0.3 mmol, 10 mol%) were added. The nitrogen atmosphere was then evacuated three times, and 1f (1.49 g, 6 mmol, 2.0 equiv) and dimethyl sulfoxide (20 mL) were added under nitrogen atmosphere. The mixture was heated to 90°C for 12 hours and then cooled to room temperature. Deionized water was added to quench the mixture, and the organic phase was extracted three times with ethyl acetate. The organic phases were combined and the solvent was removed by distillation under reduced pressure. The crude product was separated by column chromatography on silica gel with an eluent of ethyl acetate / petroleum ether = 20:1 to obtain 1.13 g of a yellow solid with a yield of 70%.

[0063] Synthesis of intermediate C-2-NH2

[0064] The synthetic route of intermediate C-2-NH2 is as follows:

[0065] (1) Add 2a (20 g, 134.01 mmol, 1.0 equivalent) and dichloromethane (200 mL) to a single-necked reaction flask equipped with a magnetic separator. Stir until dissolved, then cool to 0°C. Slowly add N-bromosuccinimide (50.09 g, 281.42 mmol, 2.1 equivalent), and return to room temperature with stirring for 24 hours. Then, add sodium thiosulfate (3.32 g, 13.4 mmol, 0.1 equivalent) to quench the mixture. Extract the organic phase three times with dichloromethane. Combine the organic phases and remove the solvent by vacuum distillation. The crude product is separated by column chromatography on silica gel with an eluent of petroleum ether / ethyl acetate = 80:1 to obtain 40.98 g of a red liquid with a yield of 99%.

[0066] (2) Add C-1-NH2 (30 g, 97.71 mmol, 1.0 equivalent) and N,N-dimethylformamide (100 mL) to a single-necked reaction flask equipped with a magnetic rod. Stir until dissolved, then cool to 0°C. Slowly add 60% sodium hydride (4.3 g, 107.48 mmol, 1.1 equivalent). Stir for 30 minutes, then add 2b (13.79 g, 97.71 mmol, 1.0 equivalent). Return to room temperature and stir for 24 hours. Then, add deionized water to quench the mixture. Extract the organic phase three times with dichloromethane. Combine the organic phases and remove the solvent by vacuum distillation. The crude product is separated by column chromatography on silica gel with an eluent of petroleum ether / dichloromethane = 6:1 to obtain 33.48 g of a red oil with a yield of 80%.

[0067] (3) C-1-NO2 (5 g, 11.68 mmol, 1.0 equiv), 2c (4.27 g, 35.04 mmol, 3.0 equiv), tetrakistriphenylphosphine palladium (270 mg, 0.26 mmol, 2 mol%), and potassium carbonate (3.23 g, 23.36 mmol, 2.0 equiv) were added to a three-necked reaction flask equipped with a magnetic rod. The nitrogen atmosphere was then evacuated three times, and toluene (30 mL) / ethanol (10 mL) / water (10 mL) were added under a nitrogen atmosphere. The mixture was heated to 90°C for 24 hours and then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by column chromatography on silica gel using petroleum ether / ethyl acetate = 40:1 as the eluent to obtain 4.52 g of a yellow solid with a yield of 91%.

[0068] (4) Add C-2-NO2 (4.52 g, 10.7 mmol, 1.0 equivalent) and stannous chloride dihydrate (9.66 g, 42.8 mmol, 4.0 equivalent) to a three-necked reaction flask with a magnetic rod. Then, replace the nitrogen three times and add ethyl acetate (30 mL) / ethanol (30 mL) under a nitrogen atmosphere. Heat to 80°C for 24 hours and then cool to room temperature. Add saturated sodium bicarbonate solution to quench the reaction. Extract the organic phase three times with ethyl acetate. Combine the organic phases and remove the solvent by vacuum distillation. The crude product is separated by column chromatography on silica gel with an eluent of petroleum ether / ethyl acetate = 5:1 to obtain 3.06 g of a yellow solid with a yield of 73%.

[0069] Synthesis of intermediate D-2-NH2

[0070] The synthetic route of intermediate D-2-NH2 is as follows:

[0071] (1) 3a (24.52 g, 97.71 mmol, 1.0 equivalent) and N,N-dimethylformamide (100 mL) were added to a single-necked reaction flask equipped with a magnetic rod. After stirring until dissolved, the temperature was lowered to 0°C. 60% sodium hydride (4.3 g, 107.48 mmol, 1.1 equivalent) was slowly added. After stirring for 30 minutes, 2b (13.79 g, 97.71 mmol, 1.0 equivalent) was added. The mixture was stirred at room temperature for 24 hours. Deionized water was then added to quench the mixture. The organic phase was extracted three times with dichloromethane. The organic phases were combined and the solvent was removed by distillation under reduced pressure. The crude product was separated by column chromatography on silica gel using a 6:1 ratio of petroleum ether to dichloromethane as the eluent to obtain 30.17 g of a red oil with a yield of 83%.

[0072] (2) D-1-NO2 (4.35 g, 11.68 mmol, 1.0 equivalent), 2-b (4.27 g, 35.04 mmol, 3.0 equivalent), tetrakistriphenylphosphine palladium (270 mg, 0.26 mmol, 2 mol%), and potassium carbonate (3.23 g, 23.36 mmol, 2.0 equivalent) were added to a three-necked reaction flask equipped with a magnetic rod. The nitrogen atmosphere was then evacuated three times, and toluene (30 mL) / ethanol (10 mL) / water (10 mL) were added under a nitrogen atmosphere. The mixture was heated to 90°C for 24 hours and then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by column chromatography on silica gel with an eluent of petroleum ether / ethyl acetate = 40:1 to obtain 3.77 g of a yellow solid with a yield of 88%.

[0073] (3) D-2-NO2 (3.92 g, 10.7 mmol, 1.0 equivalent) and stannous chloride dihydrate (9.66 g, 42.8 mmol, 4.0 equivalent) were added to a three-necked reaction flask equipped with a magnetic rod. The nitrogen atmosphere was then replaced three times, and ethyl acetate (30 mL) / ethanol (30 mL) was added under a nitrogen atmosphere. The mixture was heated to 80°C for 24 hours and then cooled to room temperature. Saturated sodium bicarbonate solution was added to quench the reaction, and the organic phase was extracted with ethyl acetate three times. The organic phases were combined and the solvent was removed by vacuum distillation. The crude product was separated by column chromatography on silica gel with an eluent of petroleum ether / ethyl acetate = 5:1 to obtain 2.52 g of a yellow solid with a yield of 70%.

[0074] Synthesis of intermediate E-1-NH2

[0075] The synthetic route of intermediate E-1-NH2 is as follows:

[0076] (1) 4a (2 g, 14.48 mmol, 1.0 eq) and N,N-dimethylformamide (20 mL) were added to a single-necked reaction flask equipped with a magnetic separator. After stirring until dissolved, the temperature was lowered to 0°C. 60% sodium hydride (636 mg, 14.94 mmol, 1.1 eq) was slowly added. After stirring for 30 minutes, 4b (2.17 g, 14.48 mmol, 1.0 eq) was added. The mixture was stirred at room temperature for 24 hours. Deionized water was then added to quench the mixture. The organic phase was extracted three times with dichloromethane. The organic phases were combined and the solvent was removed by distillation under reduced pressure. The crude product was separated by column chromatography on silica gel using a 6:1 ratio of petroleum ether to dichloromethane as the eluent to obtain 1.42 g of a red oil with a yield of 63%.

[0077] (2) Add E-2-NO2 (1.42 g, 9.15 mmol, 1.0 equivalent) and stannous chloride dihydrate (8.26 g, 36.6 mmol, 4.0 equivalent) to a three-necked reaction flask with a magnetic rod. Then, replace the nitrogen three times and add ethyl acetate (10 mL) / ethanol (10 mL) under a nitrogen atmosphere. Heat to 80°C for 24 hours and then cool to room temperature. Add saturated sodium bicarbonate solution to quench the reaction. Extract the organic phase three times with ethyl acetate. Combine the organic phases and remove the solvent by vacuum distillation. The crude product is separated by column chromatography on silica gel with an eluent of petroleum ether / ethyl acetate = 5:1 to obtain 859 mg of a black oil with a yield of 75%.

[0078] It should be noted that the above is only a feasible preparation scheme for one of the intermediates of the present invention. The synthesis processes of intermediates A-1-OH, intermediate A-2-Cl, and E-1-NH2 can be referred to to prepare the intermediates required for each example. The preparation of such intermediate compounds is not limited to this method. They can be prepared using the methods listed above or other methods known in the art. It is not intended to limit the scope of protection of the present invention.

[0079] Example 1: Synthesis of Pt-1

[0080] The synthesis route of the tetradentate ring metal platinum (II) complex phosphorescent material Pt-1 is as follows:

[0081] Synthesis of Intermediate (F-1-2NH): To a three-necked reaction flask equipped with a magnetic ion, add A-2-Cl (200 mg, 0.35 mmol, 1.0 equiv), C-2-NH2 (137 mg, 0.35 mmol, 1.0 equiv), tris(dibenzylideneacetone)dipalladium (10 mg, 0.01 mmol, 3 mol%), 2-dicyclohexylphosphino-2′,6′-dimethoxy-biphenyl (8 mg, 0.02 mmol, 6 mol%), and sodium tert-butoxide (67 mg, 0.7 mmol, 2.0 equiv). The nitrogen atmosphere was then purged three times, and toluene (10 mL) was added under a nitrogen atmosphere. The mixture was heated to 120°C for 4 hours, then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by silica gel column chromatography using petroleum ether / ethyl acetate (20:1) as the eluent to obtain 277 mg of a yellow solid in an 85% yield.

[0082] Synthesis of the ligand LYQ-1-PF6: To a three-necked reaction flask equipped with a magnetic rod, add F-1-2NH (277 mg, 0.3 mmol, 1.0 equiv) and ammonium hexafluorophosphate (98 mg, 0.6 mmol, 2.0 equiv). The nitrogen atmosphere was then purged three times, and triethyl orthoformate (5 mL) was added under a nitrogen atmosphere. The mixture was heated to 80°C for 25 minutes, then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by silica gel column chromatography using a 40:1 dichloromethane / ethyl acetate eluent to afford 173 mg of a yellow solid in a 53% yield.

[0083] Synthesis of Pt-1: To a sealed tube with a magnetic rod, add LYQ-1-PF6 (177 mg, 0.16 mmol, 1.0 equiv), (1,5-cyclooctadiene)platinum(II) dichloride (64 mg, 0.17 mmol, 1.05 equiv), and sodium acetate (39 mg, 0.48 mmol, 3.0 equiv). The nitrogen atmosphere was then purged three times, and diethylene glycol dimethyl ether (5 mL) was added under a nitrogen atmosphere. The reaction was heated to 120°C with stirring for three days, then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by silica gel column chromatography using a 2:1 ratio of petroleum ether to dichloromethane as the eluent to afford 42 mg of a cyan solid in a 23% yield. 1 H NMR(500MHz,DMSO-d6)δ9.00(s,1H),8.22(d,J=5Hz,1H),8.17(d,J=10Hz,1H),8.11(d,J=10Hz,1H),7.9 9(s,1H),7.85(d,J=5Hz,1H),7.63(t,J=15Hz,1H),7.58(d,J=10Hz,1H),7.49–7.45(m,2H),7.37(d,J=5 Hz,1H),7.25(d,J=15Hz,1H),7.18–7.11(m,5H),7.03(d,J=15Hz,1H),6.96(s,3H),6.89(d,J=10Hz,1H) ,6.77(d,J=5Hz,3H),6.47(t,J=15Hz,3H),6.03(t,J=15Hz,2H),2.05(s,3H),1.50(s,9H),1.14(s,18H).

[0084] Example 2: Synthesis of Pt-2

[0085] The synthesis route of the tetradentate ring metal platinum (II) complex phosphorescent material Pt-2 is as follows:

[0086] Synthesis of Intermediate (F-2-2NH): To a three-necked reaction flask equipped with a magnetic ion, add A-2-Cl (250 mg, 0.44 mmol, 1.0 equiv), D-2-NH2 (148 mg, 0.44 mmol, 1.0 equiv), tris(dibenzylideneacetone)dipalladium (10 mg, 0.01 mmol, 3 mol%), 2-dicyclohexylphosphino-2′,6′-dimethoxy-biphenyl (8 mg, 0.02 mmol, 6 mol%), and sodium tert-butoxide (85 mg, 0.88 mmol, 2.0 equiv). The nitrogen atmosphere was then purged three times, and toluene (10 mL) was added under a nitrogen atmosphere. The mixture was heated to 120°C for 4 hours, then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by silica gel column chromatography using petroleum ether / ethyl acetate (20:1) as the eluent to obtain 158 mg of a yellow solid in a 41% yield.

[0087] Synthesis of the ligand LYQ-2-PF6: To a three-necked reaction flask equipped with a magnetic rod, add F-2-2NH (158 mg, 0.18 mmol, 1.0 equiv) and ammonium hexafluorophosphate (59 mg, 0.36 mmol, 2.0 equiv). The nitrogen atmosphere was then purged three times, and triethyl orthoformate (5 mL) was added under a nitrogen atmosphere. The mixture was heated to 80°C for 25 minutes, then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by silica gel column chromatography using a 40:1 dichloromethane / ethyl acetate eluent to afford 144 mg of a yellow solid in a 78% yield.

[0088] Synthesis of Pt-2: LYQ-2-PF6 (144 mg, 0.14 mmol, 1.0 equiv), (1,5-cyclooctadiene)platinum(II) dichloride (56 mg, 0.15 mmol, 1.05 equiv), and sodium acetate (34 mg, 0.42 mmol, 3.0 equiv) were added to a sealed tube with a magnetic rod. The nitrogen atmosphere was then purged three times, and diethylene glycol dimethyl ether (5 mL) was added under a nitrogen atmosphere. The reaction was heated to 120°C with stirring for three days, then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by silica gel column chromatography using a 2:1 ratio of petroleum ether to dichloromethane as the eluent to afford 31 mg of a cyan solid in a 19% yield. 1H NMR(500MHz,DMSO-d6)δ8.77(s,1H),8.30(d,J=10Hz,1H),8.16(dd,J=10,5Hz,2H),8.00(s, 1H),7.80(d,J=10Hz,1H),7.63(s,2H),7.57(t,J=5Hz,1H),7.46(t,J=10Hz,1H),7.41(d,J=5 Hz,1H),7.26–7.19(m,4H),7.16(dd,J=10,5Hz,3H),7.08–7.01(m,4H),6.97(dd,J=15,10Hz, 4H),6.77(d,J=10Hz,1H),6.68(d,J=5Hz,2H),6.65–6.59(m,2H),2.28(s,3H),1.15(s,18H).

[0089] Example 3: Synthesis of Pt-3

[0090] The synthesis route of the tetradentate ring metal platinum (II) complex phosphorescent material Pt-3 is as follows:

[0091] Synthesis of Intermediate (F-3-2NH): To a three-necked reaction flask equipped with a magnetic ion, add A-3-Cl (300 mg, 0.65 mmol, 1.0 equiv), C-2-NH2 (255 mg, 0.65 mmol, 1.0 equiv), tris(dibenzylideneacetone)dipalladium (18 mg, 0.02 mmol, 3 mol%), 2-dicyclohexylphosphino-2′,6′-dimethoxy-biphenyl (16 mg, 0.04 mmol, 6 mol%), and sodium tert-butoxide (125 mg, 1.3 mmol, 2.0 equiv). The nitrogen atmosphere was then purged three times, and toluene (10 mL) was added under a nitrogen atmosphere. The mixture was heated to 120°C for 4 hours, then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by silica gel column chromatography using petroleum ether / ethyl acetate (20:1) as the eluent to obtain 441 mg of a yellow solid in a 94% yield.

[0092] Synthesis of the ligand LYQ-3-PF6: To a three-necked reaction flask equipped with a magnetic rod, add F-3-2NH (441 mg, 0.45 mmol, 1.0 equiv) and ammonium hexafluorophosphate (147 mg, 0.9 mmol, 2.0 equiv). The nitrogen atmosphere was then purged three times, and triethyl orthoformate (5 mL) was added under a nitrogen atmosphere. The mixture was heated to 80°C for 25 minutes, then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by silica gel column chromatography using a 40:1 dichloromethane / ethyl acetate eluent to afford 426 mg of a yellow solid in an 83% yield.

[0093] Synthesis of LYQ-3-Pt: LYQ-3-PF6 (250 mg, 0.22 mmol, 1.0 equiv), (1,5-cyclooctadiene)platinum(II) dichloride (85 mg, 0.23 mmol, 1.05 equiv), and sodium acetate (53 mg, 0.66 mmol, 3.0 equiv) were added to a sealed tube with a magnetic rod. The nitrogen atmosphere was then purged three times, and diethylene glycol dimethyl ether (10 mL) was added under a nitrogen atmosphere. The reaction was heated to 120°C with stirring for three days, then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by silica gel column chromatography using a 2:1 ratio of petroleum ether to dichloromethane as the eluent to afford 158 mg of a cyan solid in a 61% yield. 1 H NMR (500MHz, DMSO-d6) δ8.98(s,1H),8.22(d,J=5Hz,1H),8.10(t,J=10Hz,2H),7.98(s,1H),7.84( d,J=5Hz,1H),7.63(t,J=10Hz,1H),7.50–7.44(m,3H),7.37(d,J=5Hz,1H),7.29(t,J=10Hz,1H),7. 17–7.13(m,4H),7.05(t,J=10Hz,1H),6.98–6.95(m,3H),6.90(d,J=5Hz,1H),6.79(d,J=10Hz,3H) ,6.54–6.44(m,3H),6.05(t,J=10Hz,2H),2.05(s,3H),1.50(s,10H),1.41(s,10H),1.13(s,20H).

[0094] Example 4: Synthesis of Pt-24

[0095] The synthesis route of the tetradentate ring metal platinum (II) complex phosphorescent material Pt-24 is as follows:

[0096] Synthesis of Intermediate (F-4-2NH): To a three-necked reaction flask equipped with a magnetic ion, add A-2-Cl (250 mg, 0.44 mmol, 1.0 equiv), D-2-NH2 (148 mg, 0.44 mmol, 1.0 equiv), tris(dibenzylideneacetone)dipalladium (10 mg, 0.01 mmol, 3 mol%), 2-dicyclohexylphosphino-2′,6′-dimethoxy-biphenyl (8 mg, 0.02 mmol, 6 mol%), and sodium tert-butoxide (85 mg, 0.88 mmol, 2.0 equiv). The nitrogen atmosphere was then purged three times, and toluene (10 mL) was added under a nitrogen atmosphere. The mixture was heated to 120°C for 4 hours, then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by silica gel column chromatography using petroleum ether / ethyl acetate (20:1) as the eluent to obtain 158 mg of a yellow solid in a 41% yield.

[0097] Synthesis of the ligand LYQ-4-PF6: To a three-necked reaction flask equipped with a magnetic rod, add F-2-2NH (158 mg, 0.18 mmol, 1.0 equiv) and ammonium hexafluorophosphate (59 mg, 0.36 mmol, 2.0 equiv). The nitrogen atmosphere was then purged three times, and triethyl orthoformate (5 mL) was added under a nitrogen atmosphere. The mixture was heated to 80°C for 25 minutes, then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by silica gel column chromatography using a 40:1 dichloromethane / ethyl acetate ratio as the eluent to afford 144 mg of a yellow solid in a 78% yield.

[0098] Synthesis of Pt-24: LYQ-4-PF6 (200 mg, 0.26 mmol, 1.0 equiv), (1,5-cyclooctadiene)platinum(II) dichloride (101 mg, 0.27 mmol, 1.05 equiv), and sodium acetate (64 mg, 0.78 mmol, 3.0 equiv) were added to a sealed tube with a magnetic rod. The nitrogen atmosphere was then purged three times, and diethylene glycol dimethyl ether (10 mL) was added under a nitrogen atmosphere. The reaction was heated to 120°C with stirring for three days, then cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the crude product was separated by silica gel column chromatography using a 2:1 ratio of petroleum ether to dichloromethane as the eluent to afford 116 mg of a cyan solid in a 54% yield. 1 H NMR(500MHz,DMSO-d6)δ9.30(s,1H),8.23(d,J=10Hz,1H),8.19–8.14(m,3H),7.90(d,J=15Hz,1H),7.71(d,J=5Hz,1H ),7.57(s,1H),7.55–7.49(m,4H),7.42(dt,J=20,5Hz,2H),7.34–7.26(m,3H),6.98(s,1H),2.30(s,3H),1.44(s,9H).

[0099] Example 5: Synthesis of Pt-8

[0100] Pt-8 was synthesized by referring to the synthesis steps and reaction conditions of compound Pt-1. The target product was obtained as a yellow solid (562 mg) with a yield of 70%. Molecular weight [M+H] + :866.33.

[0101] Example 6: Synthesis of Pt-31

[0102] Pt-31 was synthesized by referring to the synthesis steps and reaction conditions of compound Pt-1. The target product was obtained as a yellow solid (624 mg) with a yield of 56%. Molecular weight [M+H] + :1018.40.

[0103] Example 7: Synthesis of Pt-37

[0104] Pt-37 was synthesized by referring to the synthesis steps and reaction conditions of compound Pt-1. The target product was obtained as a yellow solid (661 mg) with a yield of 82%. Molecular weight [M+H] + :1074.46.

[0105] Example 8: Synthesis of Pt-65

[0106] Pt-65 was synthesized using the same synthesis steps and reaction conditions as Pt-1. 484 mg of the target product was obtained as a yellow solid with a yield of 67%. Molecular weight [M+H] + :1186.58.

[0107] Example 9: Synthesis of Pt-81

[0108] Pt-81 was synthesized by referring to the synthesis steps and reaction conditions of compound Pt-1. The target product was obtained as a yellow solid (455 mg) with a yield of 60%. Molecular weight [M+H] + :1037.44.

[0109] Example 10: Synthesis of Pt-174

[0110] Pt-174 was synthesized using the same synthesis steps and reaction conditions as Pt-1. 410 mg of the target product was obtained as a yellow solid with a yield of 66%. Molecular weight [M+H] + :1279.57.

[0111] Example 11: Synthesis of Pt-183

[0112] Pt-183 was synthesized using the same synthesis steps and reaction conditions as Pt-1. 492 mg of the target product was obtained as a yellow solid with a yield of 82%. Molecular weight [M+H] + :1203.53.

[0113] Example 12: Synthesis of Pt-241

[0114] Pt-241 was synthesized using the same synthesis steps and reaction conditions as Pt-1. 467 mg of the target product was obtained as a yellow solid with a yield of 72%. Molecular weight [M+H] + :1065.48.

[0115] Example 13: Synthesis of Pt-256

[0116] Pt-256 was synthesized by referring to the synthesis steps and reaction conditions of compound Pt-1. The target product was obtained as a yellow solid (528 mg) with a yield of 68%. Molecular weight [M+H] + :924.41.

[0117] Example 14: Synthesis of Pt-273

[0118] Pt-273 was synthesized by referring to the synthesis steps and reaction conditions of compound Pt-1. The target product was obtained as a yellow solid (436 mg) with a yield of 49%. Molecular weight [M+H] + :1166.52.

[0119] Photophysical properties:

[0120] Table 1. Photophysical properties of some metal complexes in dichloromethane solution

[0121] Figure 1 shows the room-temperature emission spectra of Pt-1 to Pt-4 in dichloromethane solution. As shown in Figure 1 and Table 1, the metal complexes provided by the present invention all emit light in the blue and deep blue regions, exhibit high color purity, and have a narrow half-width at half maximum, making them excellent blue phosphorescent materials.

[0122] Fabrication of OLED devices:

[0123] As a reference preparation method for a device embodiment, the present invention deposits a p-type dopant material onto the surface of an ITO glass or anode with a luminescent area of ​​2mm×2mm, or co-evaporates the p-type dopant material with a hole injection material at a concentration of 1% to 50% to form a 5-100nm hole injection layer (HIL) and a 5-200nm hole transport layer (HTL). Subsequently, a 10-100nm light-emitting layer (EML) (which may contain the compound described herein) is formed on the hole transport layer, followed by a 20-200nm electron transport layer (ETL) and a 50-200nm cathode. If necessary, an electron blocking layer (EBL) is added between the HTL and EML layers, and an electron injection layer (EIL) is added between the ETL and cathode to produce an OLED device. The OLED device is then tested using standard methods. Unless otherwise specified, the device materials involved in this invention can be obtained by known synthesis methods.

[0124] In a preferred embodiment, the structure of device example 1 provided by the present invention is: ITO / P-4 (10 nm) / NPD (60 nm) / HTH-85 (5 nm) / platinum (II) complex: HTH-85:ETH-45 (25 nm) (Pt-1:HTH-85:ETH-45 mass ratio is 10:60:30) / ETH-5 (5 nm) / ET-14 (40 nm) / LiQ (1 nm) / Al (100 nm).

[0125] Device Examples 2 through 14 and Comparative Example 1 were prepared using structures similar to those of Device Example 1, differing only in that Pt-1 in Device Example 1 was replaced with Pt-2, Pt-3, Pt-8, Pt-24, Pt-31, Pt-37, Pt-65, Pt-81, Pt-174, Pt-183, Pt-241, Pt-256, Pt-273, and R1, respectively. The luminescence properties of the comparative examples and each device example prepared above were tested using standard methods, and the data are shown in Table 2. The device structures are as follows: where P-4 represents HATCN and ET-14 represents BPyTP.

[0126] Table 2 Device luminescence characteristics data table

[0127] As can be seen from Table 2, compared with Comparative Example 1, Device Examples 1 to 14 prepared in the present application all showed good device performance in terms of driving voltage, current efficiency and device life. The improvement in the performance of each device example is based on the specific compound material of the present invention having better electron transport capability. It can be seen that when it is used as a light-emitting layer material to prepare an electronic device, it has higher current efficiency and device life while reducing the driving voltage. In addition, the devices prepared by the present invention are all deep blue light devices, and the CIEy values ​​are all less than 0.19. It shows that the compound provided by the present invention has certain commercial application value.

[0128] In a preferred specific embodiment, the structure of device example 15 provided by the present invention is: ITO / P-4 (10nm) / NPD (60nm) / HTH-85 (5nm) / platinum (II) complex: boron-containing compound: HTH-85:ETH-45 (25nm) (Pt-1:BN1:HTH-85:ETH-45 mass ratio is 10:1:59:30) / ETH-5 (5nm) / ET-14 (40nm) / LiQ (1nm) / Al (100nm).

[0129] Device Examples 16-18 and Comparative Example 2 were prepared using structures similar to those of Device Example 11, with the only difference being that the platinum (II) complex and the boron-containing compound in Device Example 15 were replaced with the compounds listed in Table 3. The device structures and luminescence characteristics are shown in Table 3.

[0130] Table 3. Device structure and luminescence characteristics data

[0131] As shown in Table 3, the compounds of the present invention, when used as sensitizing materials in devices along with boron-containing compounds as luminescent materials, significantly improved the performance of each device. This further demonstrates that the compounds provided by the present invention have considerable commercial application value. Furthermore, the addition of boron-containing compounds to sensitize the device structure can further reduce the CIEy value, thereby further improving the color purity of the device's luminescent light.

[0132] The applicant declares that the above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the scope of protection and disclosure of the present invention.

Claims

1. A tetradentate metal platinum (II) complex based on phenylpyridine, characterized in that: The complex has a structure as shown in formula (I): In formula (I), R 1 -R 6 Each independently represents a single substitution to the maximum amount of substitution, or no substitution; R 1 -R 6 Each is independently selected from the group consisting of hydrogen, deuterium, halogen, C1-C30 alkyl, C1-C30 haloalkyl, substituted or unsubstituted C6-C60 aryl, and combinations thereof; R a , R b Each is independently selected from the group consisting of: hydrogen, deuterium, C1-C30 alkyl, substituted or unsubstituted C6-C60 aryl and combinations thereof; the substitution is deuterium, C1-C30 alkyl, C6-C60 aryl.

2. The tetradentate ring metal platinum (II) complex according to claim 1, characterized in that The R a is selected from hydrogen, deuterium, CD3, C1-C10 alkyl, C6-C30 aryl and combinations thereof; R b The group consisting of hydrogen, deuterium, C1-C20 alkyl and combinations thereof.

3. The tetradentate ring metal platinum (II) complex according to claim 1, characterized in that R 1 -R 6 Each is independently selected from hydrogen, deuterium, CD3, F, CF3, methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, pentyl, hexyl, heptyl, phenyl and combinations thereof.

4. The tetradentate ring metal platinum (II) complex according to claim 1, characterized in that The tetradentate metal platinum (II) complex is selected from any one of the chemical structures shown below, wherein "D" represents deuterium:

5. Use of the tetradentate metal platinum (II) complex according to any one of claims 1 to 4 in electronic devices, wherein the electronic devices include one or more of an organic electroluminescent device, an organic integrated circuit, an organic field effect transistor, an organic thin film transistor, an organic light emitting transistor, an organic solar cell, an organic optical detector, an organic photoreceptor, an organic field quenching device, a light emitting electrochemical cell or an organic laser diode.

6. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises a cathode, an anode and an organic functional layer therebetween; the organic functional layer comprises the tetradentate metal platinum (II) complex according to any one of claims 1 to 4.

7. An organic electroluminescent device, characterized in that: The organic functional layer comprises a light-emitting layer, and the light-emitting layer comprises the tetradentate metal platinum (II) complex according to any one of claims 1 to 4.

8. The organic electroluminescent device according to claim 7, characterized in that: The light-emitting layer also contains fluorescent doping materials.

9. An organic optoelectronic device, characterized in that: The organic photoelectric device comprises: a substrate layer; a first electrode, which is on the substrate; an organic light-emitting functional layer, which is on the first electrode; and a second electrode, which is on the organic light-emitting functional layer; wherein the organic light-emitting functional layer contains the tetradentate metal platinum (II) complex according to any one of claims 1 to 4.

10. The organic optoelectronic device according to claim 9, characterized in that: The organic light-emitting functional layer also contains fluorescent doping materials.

11. A composition, characterized in that The composition comprises the tetradentate platinum (II) complex according to any one of claims 1 to 4.

12. A preparation, characterized in that The preparation comprises the tetradentate platinum (II) complex according to any one of claims 1 to 4.

13. A display or lighting device, characterized in that: The device comprises one or more of the organic electroluminescent devices according to any one of claims 6 to 8.

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