Platinum (II) complex guest phosphorescent material with spirofluorene structure, electronic device, device and application thereof

Abstract

The invention belongs to the technical field of organic electroluminescence preparation, and particularly relates to a platinum (II) complex guest phosphorescent material with a spirofluorene structure, an electronic device, a device and application of the platinum (II) complex guest phosphorescent material. The core of the invention lies in that a rigid spirofluorene fragment with large steric hindrance is introduced into N-heterocyclic carbene of the platinum (II) complex, so that the molecular rigidity is remarkably enhanced, the structural deformation between a ground state and an excited state is reduced, and non-radiative decay caused by molecular vibration is fundamentally inhibited. Substituent groups are introduced to 2 ', 7' positions of 9, 9 '-spirobifluorene to increase steric hindrance, light-emitting quenching caused by molecular aggregation is inhibited, non-radiative transition can be further inhibited, and quantum efficiency is improved. The quantum efficiency of an organic light-emitting device manufactured by using the compound as a light-emitting layer is obviously improved.

Description

Technical Field

[0001] This invention belongs to the field of organic electroluminescence preparation technology, specifically relating to a platinum(II) complex guest phosphorescent material with a spirofluorene structure, electronic device, apparatus and its application. Background Technology

[0002] Organic light-emitting diodes (OLEDs) are a new generation of full-color display and lighting technology. Compared to liquid crystal displays (LCDs), which suffer from slow response times, narrow viewing angles, the need for backlighting, and high energy consumption, OLEDs, as self-emissive devices, do not require backlighting, making them energy-efficient. They also feature low driving voltage, fast response times, high resolution and contrast, wide viewing angles, and excellent low-temperature performance. OLED devices can be made thinner and can be fabricated into flexible structures. Furthermore, they offer advantages such as low production costs, simple manufacturing processes, and the ability to be mass-produced. Therefore, OLEDs have broad and enormous application prospects in high-end electronics and aerospace. With increasing investment, further research and development, and upgrades to production equipment, OLEDs have a very wide range of application scenarios and development prospects in the future.

[0003] The core of OLED development lies in the design and development of luminescent materials. Early OLED devices primarily used small organic molecule fluorescent materials as their luminescent agents. However, spin statistical quantum mechanics shows that under electroluminescence, the generated singlet and triplet excitons account for only 25% and 75%, respectively. Since traditional fluorescent materials can only utilize excitons in the singlet state, their maximum theoretical internal quantum efficiency is only 25%, with the remaining 75% of triplet excitons lost through non-radiative transitions. In 1998, Professor Forrest of Princeton University and Professor Thompson of the University of Southern California discovered the phosphorescence electroluminescence phenomenon of heavy metal organic complex molecules at room temperature. Due to the strong spin-orbit coupling of heavy metal atoms, excitons can more easily undergo intersystem crossing (ISC) from the singlet to the triplet state. This allows OLED devices to fully utilize all singlet and triplet excitons generated by electro-excitation, enabling the theoretical internal quantum efficiency of the luminescent material to reach 100%.

[0004] Currently used OLED devices almost entirely employ a host-guest emission mechanism in their luminescent layers. This involves doping a host material with a guest luminescent material. The host material typically has a higher energy level than the guest material, transferring energy from the host to the guest material, thus exciting it to emit light. Commonly used organic phosphorescent guest materials are heavy metal atoms such as iridium(III), platinum(II), and Pd(II). Currently, the most widely used heavy metal phosphorescent organic complex molecules are cyclic iridium(III) complexes, and their quantities are limited. The abundance of platinum in the Earth's crust and its global annual production are approximately ten times that of iridium. IrCl3, used to prepare iridium(III) complex phosphorescent materials, is a suitable candidate. . The price of H2O is also much higher than that of PtCl2 used to prepare platinum(II) complex phosphorescent materials. Furthermore, the preparation of iridium(III) complex phosphorescent materials involves four steps: iridium(III) dimer formation, iridium(III) intermediate ligand exchange, synthesis of mer-iridium(III) complexes, and isomerization from mer- to fac-iridium(III) complexes. This significantly reduces the overall yield and the cost of the raw material IrCl3. . The increased utilization of H2O raises the preparation cost of iridium(III) complex phosphorescent materials. In contrast, the preparation of platinum(II) complex phosphorescent materials involves only the final step of ligand metallization design of platinum salts, resulting in high platinum element utilization and further reducing the preparation cost. In summary, the preparation cost of platinum(II) complex phosphorescent materials is significantly lower than that of iridium(III) complex phosphorescent materials. However, the development of platinum complex materials and devices still faces some technical challenges. Improving the chemical and thermal stability of materials, avoiding redshift or luminescence quenching caused by molecular aggregation, and thus improving device lifetime and quantum efficiency are particularly important for blue and deep blue luminescent materials. These challenges significantly impact the efficiency and energy utilization of commercially available top-emission devices, thus necessitating the development of novel phosphorescent platinum(II) complexes. Summary of the Invention

[0005] The purpose of this invention is to provide a platinum(II) complex guest phosphorescent material, electronic device, apparatus, and its applications with a spirofluorene structure. This invention increases steric hindrance by introducing substituents at the 2',7' positions, avoiding redshift or luminescence quenching caused by molecular aggregation. This results in phosphorescent materials with excellent chemical and thermal stability, facilitating the fabrication of vapor-deposited OLED devices. Organic electroluminescent devices fabricated using the compounds of this invention as the emitting layer show significant improvements in both current efficiency and quantum efficiency, demonstrating great application potential in OLED displays and lighting.

[0006] The objective of this invention is achieved through the following technical solutions;

[0007] In many embodiments, the present invention provides a platinum(II) complex guest phosphorescent material having a spirofluorene structure, the platinum(II) complex guest phosphorescent material having the structure shown in formula (I):

[0008]

[0009] In formula (I), X 1 X 2 X 3 X 4 X 5 X 6 Each can be represented independently as N or CR; R a R b R c R d R e R f R g R 1 R 2 Each can be used independently to represent single substitution to the maximum amount of substitution, or no substitution.

[0010] R, R a R b R c R d R e R f R g R 1 R 2 Each is independently selected from any one or more of the following: hydrogen, deuterium, halogen, CN, C1–C30 alkyl, substituted or unsubstituted C3–C30 cycloalkyl, substituted or unsubstituted C3–C14 heterocycloalkyl, C1–C30 alkoxy, substituted or unsubstituted C6–C60 aryl, substituted or unsubstituted C5–C60 heteroaryl, C6–C60 diarylamino, and C6–C60 arylsilyl; when containing heteroatoms, the heteroatoms are selected from N, O, S, and Si; when R, R a -R g R 1 R 2 When substituted, each substituted group is independently selected from one or more of deuterium, halogen, -CN, C1–C12 alkyl, C6–C18 aryl, and C5–C18 heteroaryl; two adjacent substituents may form a fused ring structure.

[0011] Preferably, in formula (I), the hydrogen atoms can be partially or completely replaced by deuterium.

[0012] Preferably, in formula (I), X 1 X 2 X 3 X4 X 5 X 6 Choose one from N, and the rest from CR; or X 1 X 2 X 3 X 4 Choose one from N, X 5 X 6 One of them is selected from N, and the rest are selected from CR; each time R appears, it is independently selected from hydrogen, deuterium, -CN, C1–C10 alkyl, C3–C12 cycloalkyl, C6–C30 aryl.

[0013] Preferably, in formula (I) R a -R g Each of the following is independently selected from one or more of hydrogen, deuterium, F, -CN, C1–C14 alkyl, substituted or unsubstituted C3–C14 cycloalkyl, substituted or unsubstituted C3–C14 heterocycloalkyl, C1–C14 alkoxy, substituted or unsubstituted C6–C30 aryl, substituted or unsubstituted C5–C30 heteroaryl, C6–C30 diarylamino, and C6–C30 arylsilyl; when substituted, each of the substituted is independently selected from one or more of deuterium, F, -CN, C1–C10 alkyl, C3–C12 cycloalkyl, and C6–C18 aryl.

[0014] Preferably, in formula (I) R 1 R 2 Each of the following is selected, either identically or differently, from hydrogen, deuterium, F, -CN, C1–C14 alkyl, substituted or unsubstituted C3–C14 cycloalkyl, substituted or unsubstituted C3–C14 heterocycloalkyl, substituted or unsubstituted C6–C30 aryl, and substituted or unsubstituted C5–C30 heteroaryl; when substituted, each of the substituted is independently selected from deuterium, F, -CN, C1–C10 alkyl, and C6–C18 aryl.

[0015] In many implementation schemes, R, R a R b R c R d R e R f R g R 1 and R 2Each is independently selected from hydrogen, deuterium, CD3, F, CF3, -CN, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, tert-pentyl, n-hexyl, isohexyl, sec-hexyl, tert-hexyl, n-heptyl, isohexyl, sec-heptyl, tert-heptyl, n-octyl, isooctyl, sec-octyl, tert-octyl, n-nonyl, isononyl, sec-nonyl, tert-nonyl, n-decyl, isodel, sec-decyl, tert-decyl, cyclobutyl, cyclopentyl, cyclo Hexyl, adamantyl, azircyclobutyl, azircyclopentyl, azircyclohexyl, phenyl, biphenyl, naphthyl, phenanthryl, tetrahydronaphthyl, pyridyl, dimethylfluorenyl, benzofuranyl, benzothiopheneyl, dibenzofuranyl, dibenzothiopheneyl, carbazolyl, N-phenylcarbazolyl, diisopropylamino, trimethylsilyl, triphenylsilyl, spirofluorenyl; the above substituents may be further substituted by deuterium, F, methyl, ethyl, propyl, tert-butyl, or phenyl.

[0016] In many embodiments, the platinum(II) complex guest phosphorescent material with a spirofluorene structure provided by the present invention is selected from any of the following chemical structures: where “D” represents deuterium:

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023] In many embodiments, the present invention also provides the use of platinum(II) complex guest phosphorescent materials with the structure shown in formula (I) above in the fabrication of electronic devices.

[0024] Furthermore, the electronic device includes one or more of the following: organic electroluminescent device, organic optoelectronic device, organic integrated circuit, organic field-effect transistor, organic thin-film transistor, organic light-emitting transistor, organic solar cell, organic optical detector, organic photoreceptor, organic field quenching device, luminescent electrochemical cell, or organic laser diode.

[0025] In many embodiments, the present invention provides an organic electroluminescent device comprising: a cathode, an anode, and an organic functional layer therebetween, the organic functional layer comprising a light-emitting layer comprising a platinum(II) complex guest phosphorescent material having the structure shown in formula (I) above.

[0026] More preferably, the light-emitting layer further comprises a fluorescent dopant material; the fluorescent dopant material is preferably a boron-containing organic luminescent material, and more preferably a boron-containing compound.

[0027] In many embodiments, the present invention also 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; wherein the organic light-emitting functional layer comprises a platinum(II) complex guest phosphorescent material with the structure shown in formula (I) above. For example, the platinum(II) complex can be included as a luminescent material in the organic light-emitting functional layer.

[0028] Furthermore, the organic light-emitting functional layer also contains any one or more fluorescent doping materials, wherein the fluorescent doping material is preferably a boron-containing organic luminescent material, and more preferably a phosphorescently sensitizable boron-containing compound.

[0029] In this invention, organic optoelectronic devices can be fabricated by depositing metals or conductive oxides and their alloys onto a substrate using methods such as sputtering, electron beam evaporation, and vacuum deposition to form the anode. A hole injection layer, hole transport layer, light-emitting layer, air-blocking layer, and electron transport layer are then sequentially deposited onto the surface of the anode, followed by the deposition of the cathode. Alternatively, organic electroluminescent devices can be fabricated by depositing the cathode, organic functional layer, and anode onto a substrate in that order. The organic functional layer can include a multilayer structure comprising a hole injection layer, a hole transport layer, a light-emitting layer, a hole-blocking layer, and an electron transport layer. In this invention, the organic functional layer is prepared using polymer materials via solvent engineering (spin-coating, tape-casting, doctor-blading, screen-printing, inkjet printing, or thermal imaging, etc.) instead of evaporation methods, which can reduce the number of device layers.

[0030] The present invention also provides a composition comprising a platinum(II) complex guest phosphorescent material with the structure shown in formula (I) above. Preferably, the composition further comprises a fluorescent dopant material, which is preferably a boron-containing organic luminescent material, and more preferably a phosphorescently sensitizable boron-containing compound.

[0031] The present invention also provides a formulation comprising a platinum(II) complex guest phosphorescent material with the structure shown in formula (I) above and at least one solvent. The solvent is not particularly limited and may be any solvent well known to those skilled in the art.

[0032] The present invention also provides a display or lighting device comprising one or more of the organic electroluminescent devices or organic optoelectronic devices as described above.

[0033] Preferably, the organic electroluminescent device of the present invention can be applied to organic photovoltaic devices, organic light-emitting devices (OLEDs), organic solar cells (OSCs), electronic paper (e-paper), organic photosensitive materials (OPCs), organic thin-film transistors (OTFTs), organic memory elements, and lighting and display devices.

[0034] The materials used in the organic electroluminescent devices according to the present invention can be classified as top-emitting, low-emitting, or bifacial-emitting.

[0035] Compared with the prior art, the beneficial effects of the present invention are:

[0036] (1) This invention significantly enhances molecular rigidity by introducing a rigid, sterically hindered spirofluorene fragment onto the azacarbene ligand of a platinum(II) complex. This structural design effectively reduces the structural relaxation of the molecule between the ground and excited states, helps to reduce the shoulder peak, fundamentally suppresses nonradiative decay caused by molecular vibrations, and improves the color purity and quantum efficiency of the material.

[0037] (2) Substituents such as alkyl, cycloalkyl, aryl, or heteroaryl groups are introduced at the 2' and 7' positions of 9,9'-spirodifluorene to further increase the steric hindrance of the molecule. This highly sterically hindered structure can effectively suppress molecular stacking and intermolecular π-π interactions, thereby avoiding luminescence quenching caused by molecular aggregation, further suppressing nonradiative transitions, reducing nonradiative decay, and thus improving the quantum efficiency of the luminescent material. Using the compound of this invention as the luminescent layer material to fabricate organic electroluminescent devices shows a significant improvement in quantum efficiency. Attached Figure Description

[0038] Figure 1 These are the results of photophysical property tests of the cyclic platinum(II) complex Pt2 in toluene solution at room temperature;

[0039] Figure 2 The photoluminescence quantum efficiency and excited-state lifetime of the cyclic platinum(II) complex in PMMA are given. Detailed Implementation

[0040] As used in this invention, the terms "optional" or "optionally" mean that the event or situation described below may or may not occur, and the description includes both the case where the event or situation occurs and the case where it does not occur.

[0041] The term "substituted" as used in this invention is intended to encompass 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 a suitable organic compound, permissible substituents may be one or more, the same or different. For the purposes of this invention, heteroatoms (e.g., nitrogen) can have hydrogen substituents and / or any permissible substituent of the organic compound described herein, satisfying the valence bond of that heteroatom. This disclosure is not intended to limit in any way to permissible substituents of organic compounds. Similarly, the terms "substituted" or "substituted with" imply that such substitution conforms to the permissible valence bond 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 transformations (e.g., by rearrangement, cyclization, elimination, etc.)). It is also expected that, in some respects, unless explicitly stated otherwise, individual substituents can be further optionally substituted (i.e., further substituted or unsubstituted).

[0042] When defining various terms, "R" 1 "-"R 2 “R” a "-"R g "In this invention, the general symbols are used to denote various specific substituents. These symbols can be any substituent, not limited to those disclosed herein, and while they may be defined as certain substituents in one case, they may be defined as other substituents in other cases. The 'R' used in this invention..." 1 “R” 2 “R” a "-"R g "It can independently have one or more of the groups listed above. For example, if R..." 1 If it is a straight-chain alkyl group, then one hydrogen atom of the alkyl group can be optionally substituted with hydroxyl, alkoxy, alkyl, halogen, etc. Depending on the chosen group, the first group can be incorporated into the second group, or alternatively, the first group can be dangling, i.e., attached to the second group.

[0043] As used in this invention, the term "alkyl" refers to a branched or unbranched saturated hydrocarbon group with 1 to 60 carbon atoms, preferably 1 to 30 carbon atoms, and more preferably 1 to 12 carbon atoms. Examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, hexyl, heptyl, semi-alkyl, 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, sulfoxo, or mercapto groups described in this invention.

[0044] As used in this invention, the term "aryl" refers to any carbon-based aromatic group containing 6 to 60 carbon atoms, preferably 6 to 30 carbon atoms, and more preferably 6 to 18 carbon atoms. The carbon-based aromatic group includes, but is not limited to, phenyl, naphthyl, phenyl, biphenyl, phenoxyphenyl, anthracene, phenanthrene, etc. The term "aryl" also includes "heteroaryl," which is defined as a group containing an aromatic group having 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 that does not contain a heteroatom. Aryl groups can be substituted or unsubstituted. The aryl group may replace 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, azide, nitro, silyl, sulfo-oxo, or mercapto groups as described in this invention.

[0045] The term "heteroaryl" as used in this invention refers to the general term for groups obtained by replacing one or more aromatic carbon atoms in an aryl group with heteroatoms. The heteroatoms include, but are not limited to, oxygen, sulfur, nitrogen, or phosphorus atoms, preferably having 6 to 60 carbon atoms, more preferably 6 to 30 carbon atoms, particularly preferably 6 to 18 carbon atoms, and most preferably 6 to 12 carbon atoms. The linking site of the heteroaryl group can be located on a cyclic carbon atom or on a cyclic nitrogen atom. The heteroaryl group can be a monocyclic heteroaryl, a polycyclic heteroaryl, or a fused-ring heteroaryl. The monocyclic heteroaryl groups include, but are not limited to, pyridinyl, pyrimidinyl, triazinyl, furanyl, thiopheneyl, pyrroleyl, imidazolyl, etc.; the polycyclic heteroaryl groups include, but are not limited to, bipyridinyl, bipyrimidinyl, phenylpyridinyl, etc.; the fused-ring heteroaryl groups include, but are not limited to, quinolinyl, isoquinolinyl, indolyl, benzothiopheneyl, benzofuranyl, benzoxazolyl, benzoimidazolyl, benzothiazolyl, dibenzofuranyl, benzodibenzofuranyl, dibenzothiopheneyl, benzodibenzothiapheneyl, carbazolyl, benzocarbazolyl, acridinel, 9,10-dihydroacridinyl, phenoxazinyl, phenthiazinyl, phenoxthiazyl, etc., but are not limited to. The aforementioned heteroaryl groups are preferably pyridyl, pyrimidinyl, thiophene, furanyl, benzothiophene, benzofuranyl, benzooxazolyl, benzoimidazolyl, benzothiazolyl, dibenzofuranyl, dibenzothiophene, benzodibenzothiophene, benzodibenzofuranyl, carbazolyl, acridinel, phenoxazinyl, phenthiazinyl, and phenoxthialyl.

[0046] The cyclic structure described in this invention refers to two groups linked together by chemical bonds and optionally aromatized. Examples are shown below:

[0047]

[0048] The compounds disclosed herein can exhibit desired properties and have emission and / or absorption spectra that can be tuned by selecting suitable ligands. On the other hand, the invention excludes any one or more compounds, structures, or portions thereof specifically described herein.

[0049] 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.

[0050] It should be noted that the general description above and the detailed description below are merely illustrative and explanatory, and not limiting. This application can be more easily understood by referring to the following specific embodiments and examples contained therein.

[0051] 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 indicated) or specific reagents (otherwise indicated), as these are, of course, subject to variation. It should also be understood that the terminology used in this invention is for descriptive purposes only and is not intended to be limiting. While any methods and materials similar to or equivalent to those described in this invention may be used in this practice or experiment, exemplary methods and materials are described below. All raw materials and solvents used in the synthetic examples are commercially available unless otherwise specified, and the solvents were used directly without further processing.

[0052] The substrate described in this invention can be any substrate typically used in organic optoelectronic devices. It can be a glass or transparent plastic substrate, an opaque material such as silicon or stainless steel, or a flexible PI film. Different substrates have different mechanical strengths, thermal stability, transparency, surface smoothness, and water resistance, and their applications vary depending on their properties. As materials for the hole injection layer, hole transport layer, and electron injection layer, any known materials used in OLED devices can be selected, and this invention does not impose specific limitations.

[0053] Synthesis Examples

[0054] The examples of compound synthesis, composition, devices, or methods below are intended to provide a general approach to the industry and are not intended to limit the scope of this patent. While we have striven to ensure the accuracy of data (quantities, temperatures, etc.) mentioned in the patent, some errors may still exist. Unless otherwise specified, weighings are performed separately at 25°C or room temperature, and at near-normal pressure.

[0055] The examples below provide methods for preparing novel compounds, but the preparation of such compounds is not limited to these methods. In this field of expertise, since the compounds protected in this patent are easily modified and prepared, their preparation can be carried out using the methods listed below or other methods. The examples below are merely illustrative 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 with different reactants.

[0056] HPLC-MS was performed on an Agilent 6210TOF LC / MS mass spectrometer; HRMS spectra were performed on an Agilent 6210TOFLC / MS liquid chromatography-time-of-flight mass spectrometer.

[0057] Synthetic route

[0058] Example 1: The synthetic route for the tetradentate cyclic platinum(II) complex Pt1 is as follows:

[0059]

[0060] Synthesis of the intermediate chiral 1-OMe: Cl (1.2 equivalents), Cz-OMe (1.0 equivalent), Pd₂(dba)₃ (3 mol%), SPhos (12 mol%), and sodium tert-butoxide (2.0 equivalents) were added sequentially to a reaction flask. Nitrogen gas was purged three times, and toluene (25 mL) was added. The reaction mixture was stirred at 110 °C for 42 hours, and the solvent was removed by vacuum distillation. The mixture was purified by silica gel column chromatography with petroleum ether / ethyl acetate as eluent (50-10:1) to give 930 mg of 1-OMe as a yellow solid (90% yield). MS: m / z 331.18 (M+H) + .

[0061] Synthesis of the intermediate chiral 1-OH: 1-OMe (1.0 equivalent), hydrobromic acid (48%) (9 mL), and acetic acid (6 mL) were added sequentially to a reaction flask. The mixture was stirred at 120 °C for 16 hours and then cooled to room temperature. The solution was neutralized with aqueous NaHCO3, extracted with dichloromethane, dried over anhydrous sodium sulfate, filtered, and the solvent was removed by vacuum distillation. The product 1-OH was obtained by slurrying with petroleum ether / ethyl acetate, yielding 800 mg of white solid (90% yield). MS: m / z 317.16 (M+H) + .

[0062] Synthesis of the intermediate chiral 1-Cl: 1-OH (1.0 equivalent), 1-bromo-3-tert-butyl-5-chlorobenzene (1.2 equivalent), cuprous iodide (10 mol%), 2-pyridinecarboxylic acid (20 mol%), and potassium phosphate (2.0 equivalent) were added sequentially to a reaction flask. The mixture was purged with nitrogen three times, and dimethyl sulfoxide (40 mL) was added. The reaction mixture was stirred at 100 °C for 26 hours. The mixture was diluted with water, extracted three times with ethyl acetate, washed once with brine, dried over anhydrous sodium sulfate, filtered, and the solvent was removed by vacuum distillation. The solution was purified by silica gel column chromatography with an eluent ratio of petroleum ether / ethyl acetate of 20:1–10:1, yielding 549 mg of a white solid (81% yield). MS: m / z 427.16 (M+H) + .

[0063]

[0064] Synthesis of intermediates (1-2): 1-1 (1.0 equivalent), NO2-NH2 (1.0 equivalent), tris(2,3-benzylacetone)-palladium (3 mol%), 4,5-bis(2,3-phenylphosphine-9,9-dimethyloxanthracene) (6 mol%), and cesium carbonate (2.0 equivalent) were added to a three-necked flask equipped with a magnetic stirrer. The mixture was then purged with nitrogen three times, and toluene (100 mL) was added under nitrogen protection. The reaction was carried out in an oil bath at 100 °C for 22 hours, then cooled to room temperature. The mixture was extracted with ethyl acetate, washed with water, dried over sodium sulfate, and the solvent was removed by vacuum distillation. The crude product was separated and filtered using a silica gel column chromatography. A petroleum ether / ethyl acetate ratio of 20:1 yielded 10 g of a yellowish-brown solid, with a yield of 84%. 1 H NMR (500MHz, CDCl3): δ (ppm) 6.68 (dd, J=7.5, 1.0Hz, 1H), 6.74 (d, J=6.5Hz, 1H), 6.78(dt,J=7.5,1.0Hz,2H),6.83(ddd,J=8.5,7.0,1.5Hz,1H),7.10(td,J=7.5,1 .0Hz,1H),7.12–7.18(m,4H),7.27(td,J=7.5,1.0Hz,1H),7.30(d,J=7.5Hz,1H) ,7.37–7.43(m,3H),7.84–7.90(m,3H),8.33(dd,J=9.0,2.0Hz,1H),9.90(s,1H).

[0065] Synthesis of intermediates (1-3): 1-2 (1.0 equivalent) and palladium on carbon (4.5 mol%) were added to a three-necked flask equipped with a magnetic stirrer. Nitrogen was then purged three times. Ethanol (70 mL) and ethyl acetate (70 mL) were added under nitrogen protection, followed by three more purgings with hydrogen. The reaction was carried out in an oil bath at 50 °C for 17 hours under a hydrogen atmosphere. After cooling to room temperature, the solvent was removed by vacuum distillation, yielding 9.1 g of a gray solid (95% yield). 1H NMR (500MHz, CDCl3): δ (ppm) 4.04 (s, 2H), 5.91 (s, 1H), 6.31 (dd, J = 7.5, 1.0Hz, 1H), 6.70 ( dd,J=8.0,1.0Hz,1H),6.75(d,J=7.5Hz,1H),6.79(d,J=7.5Hz,2H),6.83(td,J=7.5,1.5H z,1H),6.92(dd,J=7.5,1.5Hz,1H),6.96(t,J=8.0Hz,1H),7.02–7.15(m,5H),7.33(td,J= 7.5, 1.5Hz, 1H), 7.37 (td, J = 7.5, 1.0Hz, 2H), 7.84 (d, J = 7.5Hz, 1H), 7.86 (d, J = 7.5Hz, 1H).

[0066] Synthesis of intermediates (1-4): 1-3 (1.0 equivalent), 1-Cl (1.05 equivalent), tris(dibenzylacetone)palladium (3 mol%), 4,5-bis(diphenylphosphine-9,9-dimethyloxanthracene) (6 mol%), and cesium carbonate (2.0 equivalent) were added to a three-necked flask equipped with a magnetic stirrer. The mixture was purged with nitrogen three times, and toluene (70 mL) was added under nitrogen protection. The reaction was carried out in an oil bath at 100 °C for 22 hours, then cooled to room temperature. The mixture was filtered, and the solvent was removed by vacuum distillation. The crude product was separated by silica gel column chromatography with petroleum ether / ethyl acetate as eluent (25:1) to give 15 g of a gray solid, yield 97%. MS: m / z 813.36 (M+H) + .

[0067] Synthesis of ligand L1: 1-4 (1.0 equivalent) and ammonium hexafluorophosphate (2.0 equivalent) were added to a three-necked flask equipped with a magnetic stirrer. Nitrogen was purged three times, and triethyl orthoformate (36 mL) was added under nitrogen protection. The reaction was carried out in an oil bath at 75°C for 1 hour, then cooled to room temperature. The solvent was removed by vacuum distillation, and the mixture was separated by silica gel column chromatography with dichloromethane / methanol as the eluent (100:1-50:1). 15 g of a pale yellow solid was obtained, with a yield of 84%. 1HNMR (500MHz, CDCl3): δ (ppm) 1.39 (s, 9H), 6.11 (d, J = 8.0Hz, 1H), 6.73 (d, J = 7.5Hz, 1H), 6.77 (d, J = 7.5Hz, 1H), 6.80 (d, J = 7.5Hz, 1H),6.89(td,J=7.5,1.0Hz,1H),6.98(td,J=7.5,1.0Hz,1H),7.01(dd,J=7.5,1.0Hz,1H),7.12–7.20(m,3H),7.31–7.38(m,4H), 7.38–7.46(m,4H),7.56(d,J=8.0Hz,1H),7.61(d,J=1.0Hz,1H),7.65–7.73(m,5H),7.74–7.82(m,2H),7.86(d,J=7.5Hz,1H),7.8 8(d,J=7.5Hz,1H),7.99(d,J=8.5Hz,1H),8.09(d,J=7.5Hz,1H),8.14(d,J=8.5Hz,1H),8.58(dd,J=5.5,1.0Hz,1H),9.58(s,1H).

[0068] Synthesis of Pt1: L1 (12.00 g, 12.30 mmol, 1.0 equivalent), (1,5-cyclooctadiene)diplatinum chloride (4.60 g, 12.30 mmol, 1.0 equivalent), and sodium acetate (3.02 g, 36.90 mmol, 3.0 equivalent) were added to a three-necked flask equipped with a magnetic stirrer. Nitrogen gas was purged three times. Under nitrogen protection, N,N-dimethylformamide (460 mL) was added, and the mixture was bubbled with nitrogen for 30 min to remove oxygen. The reaction was carried out in an oil bath at 150 °C for 24 hours. After cooling to room temperature, the solvent was removed by vacuum distillation. The crude product was separated by silica gel column chromatography with petroleum ether / dichloromethane at a ratio of 3:1 to 1:1, yielding 3.20 g of a yellow solid (36% yield). 1H NMR (500MHz, CDCl3): δ (ppm) 1.04 (s, 9H), 6.11 (dd, J = 6.5, 2.0Hz, 1H), 6.74 (dd, J = 8.0, 1.0Hz, 1H), 6.77–6.83 (m, 2H), 6.86 (d, J = 7.0Hz, 1H), 6.88–6.96 (m,2H),7.09(d,J=8.0Hz,3H),7.21(td,J=7.5,1.0Hz,1H),7.25(td,J=7.0, 1.0Hz,1H),7.27–7.32(m,2H),7.33(dd,J=7.5,1.0Hz,1H),7.36(td,J=7.0, 1.5Hz,1H)7.39–7.44(m,2H),7.46(d,J=8.0Hz,1H),7.48–7.54(m,2H),7.6 3(d,J=7.5Hz,1H),7.74(d,J=7.5Hz,1H),7.79(d,J=7.5Hz,1H),7.83(d,J=8 .0Hz,1H),7.91(d,J=7.5Hz,1H),7.93(d,J=2.0Hz,1H),7.95(d,J=7.5Hz,1H ),8.03(dd,J=7.5,1.0Hz,1H),8.30(d,J=8.5Hz,1H),8.89(d,J=6.5Hz,1H).

[0069] Example 2: The synthetic route for the tetradentate cyclic platinum(II) complex Pt2 is as follows:

[0070]

[0071] Synthesis of intermediate (2-2): 2-1 (1.0 equivalent), NO2-NH2 (1.0 equivalent), tris(2-benzylacetone) dipalladium (3 mol%), 4,5-bis(diphenylphosphine-9,9-dimethyloxanthracene) (6 mol%), and cesium carbonate (2.0 equivalent) were added to a three-necked flask equipped with a magnetic stirrer. The mixture was then purged with nitrogen three times, and toluene (100 mL) was added under nitrogen protection. The reaction was carried out in an oil bath at 100 °C for 15 hours, then cooled to room temperature. The mixture was extracted with ethyl acetate, washed with water, dried over sodium sulfate, and the solvent was removed by vacuum distillation. The crude product was separated and filtered using a silica gel column chromatography. Petroleum ether / ethyl acetate ratio of 20:1 yielded 4 g of a light yellow solid, 84% yield. MS: m / z 565.28 (M+H) + .

[0072] Synthesis of intermediate (2-3): 2-2 (1.0 equivalent) and palladium on carbon (4.5 mol%) were added to a three-necked flask equipped with a magnetic stirrer. Nitrogen was then purged three times. Ethanol (30 mL) and ethyl acetate (30 mL) were added under nitrogen protection, followed by three purgings with hydrogen. The reaction was carried out in an oil bath at 50 °C for 15 hours under a hydrogen atmosphere. After cooling to room temperature, the solvent was removed by vacuum distillation, yielding 3.6 g of a gray solid (94% yield). MS: m / z 535.30 (M+H) + .

[0073] Synthesis of intermediates (2-4): 2-3 (1.0 equivalent), 1-Cl (1.05 equivalent), tris(dibenzylacetone)palladium (3 mol%), 4,5-bis(diphenylphosphine-9,9-dimethyloxanthracene) (6 mol%), and cesium carbonate (2.0 equivalent) were added to a three-necked flask equipped with a magnetic stirrer. The mixture was purged with nitrogen three times, and toluene (70 mL) was added under nitrogen protection. The reaction was carried out in an oil bath at 100 °C for 12 hours, then cooled to room temperature. The mixture was filtered, and the solvent was removed by vacuum distillation. The crude product was separated by silica gel column chromatography with petroleum ether / ethyl acetate as eluent (25:1) to give 5.2 g of a gray solid, yield 90%. MS: m / z 925.48 (M+H) + .

[0074] Synthesis of ligand L2: 2-4 (1.0 equivalent) and ammonium hexafluorophosphate (2.0 equivalent) were added to a three-necked flask equipped with a magnetic stirrer. The mixture was purged with nitrogen three times. Triethyl orthoformate (36 mL) was added under nitrogen protection. The reaction was carried out in an oil bath at 75°C for 1 hour, then cooled to room temperature. The solvent was removed by vacuum distillation. Separation was performed by silica gel column chromatography with dichloromethane / methanol as the eluent (100:1-50:1), yielding 5.1 g of a pale yellow solid (85% yield). MS: m / z 936.47 (M+H) + .

[0075] Synthesis of Pt2: L2 (1.0 equivalent), (1,5-cyclooctadiene)diplatinum chloride (1.0 equivalent), and sodium acetate (3.0 equivalent) were added to a three-necked flask equipped with a magnetic stirrer. The mixture was purged with nitrogen three times. Under nitrogen protection, N,N-dimethylformamide (240 mL) was added, and the mixture was bubbled with nitrogen for 30 min to remove oxygen. The reaction was carried out in an oil bath at 150 °C for 24 hours. After cooling to room temperature, the solvent was removed by vacuum distillation. The crude product was separated by silica gel column chromatography with petroleum ether / dichloromethane as the eluent (3:1-1:1), yielding 1.50 g of a yellow solid (43% yield). 1H NMR (500MHz,, CDCl3): δ (ppm) 0.92 (s, 9H), 1.10 (s, 18H), 6.25 (dd, J = 6.5, 2.0Hz, 1H), 6.69 (d, J = 1.5Hz, 2H), 6.74 (d, J = 2.0Hz, 1H) ,6.82(d,J=7.5Hz,1H),7.01–7.10(m,2H),7.13(d,J=8.0Hz,1H),7.18–7.25(m,2H),7.26–7.34(m,4H),7.39–7.47(m,3H),7.51(td d,J=8.5,7.5,1.0Hz,2H),7.64(dd,J=6.0,3.0Hz,1H),7.67(d,J=1.5Hz,1H),7.76–7.81(m,1H),7.84(d,J=8.0Hz,1H),7.89(d,J= 2.0Hz,1H),7.92(d,J=7.5Hz,1H),7.97(d,J=7.5Hz,1H),8.03(dd,J=6.0,2.5Hz,1H),8.32(d,J=8.5Hz,1H),8.89(d,J=6.0Hz,1H).

[0076] Example 3: Tetradentate ring platinum(II) complex Pt3

[0077] Complex Pt3 was synthesized using the same method as in Example 1 for complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final result was 118 mg of a yellow solid, with a yield of 41%. MS: m / z 1044.32 (M+H) + .

[0078] Example 4: Tetradentate ring platinum(II) complex Pt7

[0079] Complex Pt7 was synthesized using the same method as in Example 1 for complex Pt1, with the only difference being the replacement of the corresponding ligand precursor in Example 1. The final result was 160 mg of a yellow solid, with a yield of 32%. MS: m / z 1284.51 (M+H) + .

[0080] Example 5: Tetradentate ring platinum(II) complex Pt13

[0081] Complex Pt13 was synthesized using the same method as in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final yield was 114 mg of a yellow solid, with a yield of 32%. MS: m / z 1180.44 (M+H) + .

[0082] Example 6: Tetradentate ring platinum(II) complex Pt14

[0083] Complex Pt14 was synthesized using the same method as in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final yield was 198 mg of a yellow solid, with a yield of 33%. MS: m / z 1066.28 (M+H) + .

[0084] Example 7: Tetradentate ring platinum(II) complex Pt15

[0085] Complex Pt15 was synthesized using the same method as in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final yield was 119 mg of a yellow solid, with a yield of 32%. MS: m / z 1152.2 (M+H) + .

[0086] Example 8: Tetradentate ring platinum(II) complex Pt17

[0087] Complex Pt17 was synthesized using the same method as in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final yield was 125 mg of a yellow solid, with a yield of 35%. MS: m / z 1182.44 (M+H) + .

[0088] Example 9: Tetradentate ring platinum(II) complex Pt18

[0089] Complex Pt18 was synthesized using the same method as in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final product was a yellow solid, 153 mg, with a yield of 25%. MS: m / z 1168.35 (M+H) + .

[0090] Example 10: Tetradentate ring platinum(II) complex Pt20

[0091] Complex Pt20 was synthesized using the same method as in Example 1 for synthesizing complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final result was 125 mg of a yellow solid, with a yield of 29%. MS: m / z 1170.35 (M+H) + .

[0092] Example 11: Tetradentate ring platinum(II) complex Pt24

[0093] Complex Pt24 was synthesized using the same method as in Example 1 for complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 167 mg of a yellow solid, with a yield of 33%. MS: m / z 1224.41 (M+H) + .

[0094] Example 12: Tetradentate ring platinum(II) complex Pt25

[0095] Complex Pt25 was synthesized using the same method as in Example 1 for synthesizing complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final result was 128 mg of a yellow solid, with a yield of 40%. MS: m / z 1226.41 (M+H) + .

[0096] Example 13: Tetradentate ring platinum(II) complex Pt26

[0097] Complex Pt26 was synthesized using the same method as in Example 1 for complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 125 mg of a yellow solid, with a yield of 36%. MS: m / z 1147.53 (M+H) + .

[0098] Example 14: Tetradentate ring platinum(II) complex Pt29

[0099] Complex Pt29 was synthesized using the same method as complex Pt1 in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final yield was 145 mg of a yellow solid, with a yield of 32%. MS: m / z 1144.52 (M+H) + .

[0100] Example 15: Tetradentate ring platinum(II) complex Pt30

[0101] Complex Pt30 was prepared using the same synthetic method as complex Pt1 in Example 1, with the only difference being the replacement of the corresponding ligand precursor in Example 1. The final yield was 132 mg of a yellow solid, with a yield of 36%. MS: m / z 1153.57 (M+H) + .

[0102] Example 16: Tetradentate ring platinum(II) complex Pt32

[0103] Complex Pt32 was synthesized using the same method as in Example 1 for synthesizing complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 127 mg of a yellow solid, with a yield of 28%. MS: m / z 1147.54 (M+H)+ .

[0104] Example 17: Tetradentate ring platinum(II) complex Pt34

[0105] Complex Pt34 was synthesized using the same method as in Example 1 for complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final result was 145 mg of a yellow solid, with a yield of 32%. MS: m / z 1135.46 (M+H) + .

[0106] Example 18: Tetradentate ring platinum(II) complex Pt36

[0107] Complex Pt36 was synthesized using the same method as in Example 1 for synthesizing complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 153 mg of a yellow solid, with a yield of 37%. MS: m / z 1148.39 (M+H) + .

[0108] Example 19: Tetradentate ring platinum(II) complex Pt38

[0109] Complex Pt38 was synthesized using the same method as complex Pt1 in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final yield was 140 mg of a yellow solid, with a yield of 39%. MS: m / z 1149.38 (M+H) + .

[0110] Example 20: Tetradentate ring platinum(II) complex Pt40

[0111] Complex Pt40 was prepared using the same synthetic method as complex Pt1 in Example 1, with the only difference being the replacement of the corresponding ligand precursor in Example 1. The final yield was 132 mg of a yellow solid, with a yield of 40%. MS: m / z 1260.51 (M+H) + .

[0112] Example 21: Tetradentate ring platinum(II) complex Pt42

[0113] Complex Pt42 was synthesized using the same method as in Example 1 for synthesizing complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 113 mg of a yellow solid, with a yield of 32%. MS: m / z 1102.37 (M+H) + .

[0114] Example 22: Tetradentate ring platinum(II) complex Pt45

[0115] Complex Pt45 was synthesized using the same method as in Example 1 for synthesizing complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 106 mg of a yellow solid, with a yield of 36%. MS: m / z 1141.41 (M+H) + .

[0116] Example 23: Tetradentate ring platinum(II) complex Pt48

[0117] Complex Pt48 was synthesized using the same method as in Example 1 for complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 126 mg of a yellow solid, with a yield of 39%. MS: m / z 1206.46 (M+H) + .

[0118] Example 24: Tetradentate ring platinum(II) complex Pt50

[0119] Complex Pt50 was prepared using the same synthetic method as complex Pt1 in Example 1, with the only difference being the replacement of the corresponding ligand precursor in Example 1. The final yield was 122 mg of a yellow solid, with a yield of 41%. MS: m / z 1163.40 (M+H) + .

[0120] Example 25: Tetradentate ring platinum(II) complex Pt52

[0121] Complex Pt52 was synthesized using the same method as in Example 1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 118 mg of a yellow solid, with a yield of 30%. MS: m / z 1142.43 (M+H) + .

[0122] Example 26: Tetradentate ring platinum(II) complex Pt55

[0123] Complex Pt55 was synthesized using the same method as in Example 1 for synthesizing complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final result was 102 mg of a yellow solid, with a yield of 29%. MS: m / z 1153.41 (M+H) + .

[0124] Example 27: Tetradentate ring platinum(II) complex Pt58

[0125] Complex Pt58 was synthesized using the same method as in Example 1 for complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 138 mg of a yellow solid, with a yield of 37%. MS: m / z 1218.43 (M+H)+ .

[0126] Example 28: Tetradentate ring platinum(II) complex Pt59

[0127] Complex Pt59 was synthesized using the same method as in Example 1 for synthesizing complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 107 mg of a yellow solid, with a yield of 31%. MS: m / z 1286.53 (M+H) + .

[0128] Example 29: Tetradentate ring platinum(II) complex Pt60

[0129] Complex Pt60 was prepared using the same synthetic method as complex Pt1 in Example 1, with the only difference being the replacement of the corresponding ligand precursor in Example 1. The final yield was 115 mg of a yellow solid, with a yield of 33%. MS: m / z 1293.48 (M+H) + .

[0130] Example 30: Tetradentate ring platinum(II) complex Pt61

[0131] Complex Pt61 was synthesized using the same method as in Example 1 for synthesizing complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 122 mg of a yellow solid, with a yield of 37%. MS: m / z 1153.41 (M+H) + .

[0132] Example 31: Tetradentate ring platinum(II) complex Pt64

[0133] Complex Pt64 was synthesized using the same method as in Example 1 for synthesizing complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 133 mg of a yellow solid, with a yield of 35%. MS: m / z 1196.41 (M+H) + .

[0134] Example 32: Tetradentate ring platinum(II) complex Pt66

[0135] Complex Pt66 was synthesized using the same method as in Example 1 for complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 122 mg of a yellow solid, with a yield of 44%. MS: m / z 1366.52 (M+H) + .

[0136] Example 33: Tetradentate ring platinum(II) complex Pt71

[0137] Complex Pt71 was synthesized using the same method as in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final yield was 127 mg of a yellow solid, with a yield of 31%. MS: m / z 1106.30 (M+H) + .

[0138] Example 34: Tetradentate ring platinum(II) complex Pt78

[0139] Complex Pt78 was synthesized using the same method as in Example 1 for complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 123 mg of a yellow solid, with a yield of 37%. MS: m / z 1153.41 (M+H) + .

[0140] Example 35: Tetradentate ring platinum(II) complex Pt82

[0141] Complex Pt82 was synthesized using the same method as in Example 1 for synthesizing complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 134 mg of a yellow solid, with a yield of 40%. MS: m / z 1184.48 (M+H) + .

[0142] Example 36: Tetradentate ring platinum(II) complex Pt84

[0143] Complex Pt84 was synthesized using the same method as in Example 1 for synthesizing complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 163 mg of a yellow solid, with a yield of 38%. MS: m / z 1228.45 (M+H) + .

[0144] Example 37: Tetradentate ring platinum(II) complex Pt89

[0145] Complex Pt89 was synthesized using the same method as in Example 1 for complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 101 mg of a yellow solid, with a yield of 41%. MS: m / z 1153.41 (M+H) + .

[0146] Example 38: Tetradentate ring platinum(II) complex Pt95

[0147] Complex Pt95 was synthesized using the same method as in Example 1 for synthesizing complex Pt1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 153 mg of a yellow solid, with a yield of 31%. MS: m / z 1262.53 (M+H)+ .

[0148] Example 39: Tetradentate ring platinum(II) complex Pt98

[0149] Complex Pt98 was prepared using the same synthetic method as complex Pt1 in Example 1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 101 mg of a yellow solid, with a yield of 41%. MS: m / z 1300.61 (M+H) + .

[0150] Example 40: Tetradentate ring platinum(II) complex Pt106

[0151] Complex Pt106 was synthesized using the same method as in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final yield was 101 mg of a yellow solid, with a yield of 41%. MS: m / z 1522.59 (M+H) + .

[0152] Example 41: Tetradentate ring platinum(II) complex Pt113

[0153] Complex Pt113 was synthesized using the same method as in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final yield was 161 mg of a yellow solid, with a yield of 37%. MS: m / z 1134.33 (M+H) + .

[0154] Example 42: Tetradentate ring platinum(II) complex Pt118

[0155] Complex Pt118 was synthesized using the same method as in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final yield was 101 mg of a yellow solid, with a yield of 41%. MS: m / z 1112.31 (M+H) + .

[0156] Example 43: Tetradentate ring platinum(II) complex Pt122

[0157] Complex Pt122 was synthesized using the same method as in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final yield was 111 mg of a yellow solid, with a yield of 43%. MS: m / z 1282.40 (M+H) + .

[0158] Example 44: Tetradentate ring platinum(II) complex Pt126

[0159] Complex Pt126 was synthesized using the same method as in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final yield was 131 mg of a yellow solid, with a yield of 35%. MS: m / z 1204.45 (M+H) + .

[0160] Example 45: Tetradentate ring platinum(II) complex Pt132

[0161] Complex Pt132 was synthesized using the same method as in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final yield was 111 mg of a yellow solid, with a yield of 25%. MS: m / z 1129.41 (M+H) + .

[0162] Example 46: Tetradentate ring platinum(II) complex Pt136

[0163] Complex Pt136 was synthesized using the same method as in Example 1, except that the ligand precursor for the corresponding fragment was replaced. The final yield was 196 mg of a yellow solid, with a yield of 27%. MS: m / z 1462.66 (M+H) + .

[0164] Example 47: Tetradentate ring platinum(II) complex Pt137

[0165] Complex Pt137 was prepared using the same synthetic method as in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final yield was 131 mg of a yellow solid, with a yield of 38%. MS: m / z 1535.77 (M+H) + .

[0166] Example 48: Tetradentate ring platinum(II) complex Pt138

[0167] Complex Pt138 was prepared using the same synthetic method as in Example 1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 128 mg of a yellow solid, with a yield of 29%. MS: m / z 1366.54 (M+H) + .

[0168] Example 49: Tetradentate ring platinum(II) complex Pt139

[0169] Complex Pt139 was prepared using the same synthetic method as in Example 1, with the only difference being the substitution of the corresponding ligand precursor in Example 1. The final yield was 140 mg of a yellow solid, with a yield of 30%. MS: m / z 1339.43 (M+H) + .

[0170] Example 50: Tetradentate ring platinum(II) complex Pt140

[0171] Complex Pt140 was prepared using the same synthetic method as in Example 1, except that the ligand precursor of the corresponding fragment was replaced. The final yield was 152 mg of a yellow solid, with a yield of 33%. MS: m / z 1294.49 (M+H) + .

[0172] Photophysical properties:

[0173] Figure 1 These are the results of photophysical property tests of the cyclic platinum(II) complex Pt2 in toluene solution at room temperature; Figure 2 The photoluminescence quantum efficiency and excited-state lifetime of a cyclic platinum(II) complex (5% by mass) in polymethyl methacrylate (PMMA) are given. Figure 1 It is known that the emission wavelength of the platinum metal complex phosphorescent material Pt2 is in the blue light emission region at around 462 nm; the full width at half maximum (FWHM) is small, only 21 nm, indicating high color purity; [The remaining text appears to be incomplete and requires further context.] Figure 2 It is known that in polymethyl methacrylate (PMMA), the quantum efficiency of Pt1 is 82%, while that of Pt2 is as high as 90%. The excited state lifetime of Pt1 is only 2.25 microseconds, while that of Pt2 is 2.82 microseconds.

[0174] Fabrication of OLED devices:

[0175] An OLED device is fabricated by depositing p-doped material onto the surface or anode of an ITO glass with a light-emitting area of ​​2.5 mm × 2.5 mm, or by co-evaporating p-doped material with hole injection material at a concentration of 1% to 50% to form a 5-100 nm hole injection layer (HIL) and a 5-200 nm hole transport layer (HTL). Subsequently, a 10-100 nm light-emitting layer (EML) (which may contain the compound described in this invention) is formed on the hole transport layer, followed by a 20-200 nm electron transport layer (ETL) and a 50-200 nm 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 the cathode. The OLED is then tested using standard methods. Unless otherwise specified, the device materials involved in this invention can be obtained using known synthesis methods.

[0176] In a preferred embodiment, the structure of the device Example 1 provided by the present invention is: ITO / P-4 (10nm) / HT1 (60nm) / HTH-85 (5nm) / platinum (II) complex:HTH-85:ETH-45 (25nm) (Pt1:HTH-85:ETH-45 mass ratio is 10:60:30) / ETH-5 (5nm) / ET-14 (40nm) / LiQ (1nm) / Al (100nm).

[0177] Device Examples 2-38 and Comparative Example 1 were fabricated using structures similar to those in Device Example 1, the only difference being that the Pt1 in Device Example 1 was replaced with the platinum(II) complex shown in Table 1. The luminescence properties of the comparative examples and each device example prepared above were tested using standard methods and are shown in Table 1. The device structural formulas involved are as follows: where P-4 is HATCN and ET-14 is BPyTP.

[0178]

[0179] Table 1. Luminescence properties of some compounds after fabrication into devices

[0180]

[0181]

[0182] As shown in Table 1, compared with Comparative Example 1, Device Examples 1-38 prepared in this application exhibit excellent device performance in terms of driving voltage and external quantum efficiency. The performance improvement of each device example is based on the high chemical stability and better electron transport capability of the specific compound material of this invention. Furthermore, all devices prepared in this invention are deep blue light devices. It is evident that using this material as a light-emitting layer to prepare electronic devices results in higher external quantum efficiency while reducing the driving voltage. This indicates that the compound provided by this invention has certain commercial application value.

[0183] In a preferred embodiment, the structure of device example 39 provided by the present invention is as follows: ITO / P-4 (10nm) / HT1 (60nm) / HTH-85 (5nm) / platinum (II) complex: boron-containing compound: HTH-85:ETH-45 (25nm) (Pt1:BN1-8:HTH-85:ETH-45 mass ratio is 10:1:59:30) / ETH-5 (5nm) / ET-14 (40nm) / LiQ (1nm) / Al (100nm).

[0184] Device Examples 40-45 were fabricated using a structure similar to that of Device Example 39, the only difference being that the Pt2:BN1-8 in Device Example 39 was replaced with platinum(II) complexes: boron-containing compounds as listed in Table 2. The structural formulas of the devices involved are as follows, where "D" represents deuterium, and the device structure and luminescence characteristics data are shown in Table 2.

[0185]

[0186] Table 2. Device Structure and Luminescent Properties Data

[0187]

[0188]

[0189] As shown in Table 2, when the compounds of this invention are used as sensitizing materials, together with boron-containing compounds as luminescent materials in devices, the performance of each device is significantly improved. This further demonstrates that the compounds provided by this invention have certain commercial application value. Adding boron-containing compounds to sensitize the device structure can further reduce the emission spectral width, thereby improving the device's quantum efficiency.

[0190] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A platinum(II) complex guest phosphorescent material with a spirofluorene structure, characterized in that, The platinum(II) complex guest phosphorescent material has the structure shown in formula (I): In formula (I), X 1 X 2 X 3 X 4 X 5 X 6 Each can be represented independently as N or CR; R a R b R c R d R e R f R g R 1 R 2 Each can be used independently to represent single substitution to the maximum amount of substitution, or no substitution. R, R a R b R c R d R e R f R g R 1 R 2 Each is independently selected from any one or more of the following: hydrogen, deuterium, halogen, CN, C1–C30 alkyl, substituted or unsubstituted C3–C30 cycloalkyl, substituted or unsubstituted C3–C14 heterocycloalkyl, C1–C30 alkoxy, substituted or unsubstituted C6–C60 aryl, substituted or unsubstituted C5–C60 heteroaryl, C6–C60 diarylamino, and C6–C60 arylsilyl; when containing heteroatoms, the heteroatoms are selected from N, O, S, and Si; when R, R a -R g R 1 R 2 When substituted, each substituted group is independently selected from one or more of deuterium, halogen, -CN, C1–C12 alkyl, C6–C18 aryl, and C5–C18 heteroaryl; two adjacent substituents may form a fused ring structure.

2. The platinum(II) complex guest phosphorescent material according to claim 1, characterized in that, In formula (I), X 1 X 2 X 3 X 4 X 5 X 6 Choose one from N, and the rest from CR; or X 1 X 2 X 3 X 4 Choose one from N, X 5 X 6 One of them is selected from N, and the rest are selected from CR; each time R appears, it is independently selected from hydrogen, deuterium, -CN, C1–C10 alkyl, C3–C12 cycloalkyl, C6–C30 aryl; R a -R g Each is independently selected from any one or more of hydrogen, deuterium, F, -CN, C1–C14 alkyl, substituted or unsubstituted C3–C14 cycloalkyl, substituted or unsubstituted C3–C14 heterocycloalkyl, C1–C14 alkoxy, substituted or unsubstituted C6–C30 aryl, substituted or unsubstituted C5–C30 heteroaryl, C6–C30 diarylamino, and C6–C30 arylsilyl; when R a -R g When substituted, each substituted substance is independently selected from one or more of deuterium, F, -CN, C1–C10 alkyl, C3–C12 cycloalkyl, and C6–C18 aryl; R 1 R 2 Each is independently selected from any one or more of hydrogen, deuterium, F, -CN, C1–C14 alkyl, substituted or unsubstituted C3–C14 cycloalkyl, substituted or unsubstituted C3–C14 heterocycloalkyl, substituted or unsubstituted C6–C30 aryl, and substituted or unsubstituted C5–C30 heteroaryl; when R 1 R 2 When substituted, each substituted element is independently selected from one or more of deuterium, F, -CN, C1–C10 alkyl, and C6–C18 aryl.

3. The platinum(II) complex guest phosphorescent material according to claim 1, characterized in that, The phosphorescent material is selected from any one of the chemical structures shown below, where "D" represents deuterium:

4. The application of the platinum(II) complex guest phosphorescent material according to any one of claims 1-3 in the fabrication of electronic devices.

5. The application according to claim 4, characterized in that, The electronic devices include one or more of the following: organic electroluminescent devices, organic optoelectronic devices, organic integrated circuits, organic field-effect transistors, organic thin-film transistors, organic light-emitting transistors, organic solar cells, organic optical detectors, organic photosensors, organic field quenching devices, luminescent electrochemical cells, or organic laser diodes.

6. An organic electroluminescent device, characterized in that, The organic electroluminescent device comprises a cathode, an anode, and an organic functional layer between the two; the organic functional layer includes a light-emitting layer, which contains a platinum(II) complex guest phosphorescent material as described in any one of claims 1-3.

7. The organic electroluminescent device according to claim 6, characterized in that, The light-emitting layer also contains a fluorescent dopant material, which is a boron-containing compound.

8. An organic optoelectronic device, characterized in that, The organic optoelectronic device comprises: 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; wherein the organic light-emitting functional layer comprises a platinum(II) complex guest phosphorescent material as described in any one of claims 1-3.

9. A composition, characterized in that, The composition comprises a platinum(II) complex guest phosphorescent material as described in any one of claims 1-3.

10. A formulation, characterized in that, The formulation comprises a platinum(II) complex guest phosphorescent material as described in any one of claims 1-3.

11. A display or lighting device, characterized in that, The device comprises one or more of the organic electroluminescent device of claim 6 or the organic optoelectronic device of claim 8.

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