Divalent platinum complexes and their applications as blue phosphorescent materials in organic optoelectronic devices

Abstract

The present invention belongs to the technical field of organic electroluminescent materials, and provides a divalent tetradentate platinum complex, its application and an organic light emitting diode device. The divalent tetradentate platinum complex provided by the present invention has a chemical structure described in Formula I, and is a blue phosphorescent luminescent material. This blue light luminescent material is used as a doping material in OLED light emitting devices and equipment, and the peak value of the blue light emitted by it is between 460-470nm, which is a low-energy blue light with little damage to the eyes. The present invention introduces pyridoimidazole carbene and pyrazolpyridine into the ligand structure of the divalent platinum complex, the pyridoimidazole carbene structure has a suitable triplet energy, and the other part is a pyrazolpyridine N^C coordination structure with a suitable energy level; the molecule has very good stability in photoluminescence and device electroluminescence, which is conducive to promoting the development of blue light luminescent materials and improving the performance of light emitting devices.

Description

Technical Field

[0001] The present invention relates to the technical field of photoelectric material application, and in particular to the preparation of a divalent platinum complex blue phosphorescent material and the preparation and application technology of an organic photoelectric device thereof. Background Art

[0002] Compounds capable of absorbing and / or emitting light can be used in a variety of optical and optoelectronic devices, including but not limited to light absorbing devices such as solar energy, photosensitivity, organic light emitting diodes (OLEDs), light emitting devices, or devices that have both light absorbing and light emitting capabilities, and related applications for biomarkers. In order to discover organic and organometallic materials for optical and electroluminescent devices, much research has been done in this field. The research on optoelectronic materials (red and green organometallic phosphorescent materials, blue organic fluorescent materials) that can be used in light emitting and lighting devices has made significant progress and has been successful in the application of organic light emitting diode (OLED) lighting and advanced displays. However, the current application in large-scale display devices still has disadvantages such as short luminous life, high heat generation and low actual efficiency.

[0003] It is generally believed that short-wavelength blue light (high-energy blue light) between 400 and 450 nm is the most harmful to the eyes, which can cause digital visual fatigue and affect sleep, and ultimately lead to myopia, cataracts, and macular degeneration. Eye pathological hazards and human rhythm hazards. Designing a blue light source with a light emission range between 450-500 nm and applying it to related electronic products can fundamentally solve the problem of high-energy blue light in today's electronic devices causing harm to the human body.

[0004] However, compared with red and green luminescent materials and their applications, the current high-efficiency blue phosphorescent devices cannot meet the needs of commercial applications. Excellent blue light emitting materials are even rarer, and the structure of blue phosphorescent devices also needs to be broken through. High-efficiency phosphorescent blue light material molecules with stable structures and suitable luminescence spectra are the core luminescent materials for exploring blue phosphorescent devices, and are also the key factors in solving the luminescence of high-efficiency and stable blue light devices. Compared with the lowest triplet excited state energy of red and green phosphors, the lowest triplet excited state energy of blue phosphors is very high, which means that the lowest triplet excited state energy of the main material of the blue device must be higher. Therefore, the types of organic optoelectronic devices that can reach the blue light emission range are relatively limited. Correspondingly, it is more difficult to regulate the appropriate blue light spectrum so that the blue light emitting device exhibits excellent performance during the luminescence process. The nitrogen-carbene coordination structure has the characteristics of high energy level and good luminescence effect, so it can be designed in the structure of blue phosphorescent material devices. Therefore, the new nitrogen-carbene coordination structure has practical significance in the application of OLED blue phosphorescent luminescence.

[0005] At present, there are few blue phosphorescent molecular structures with good performance, and it is necessary to explore and discover new skeleton structure systems. This patent makes improvements based on CN110551157A, introducing N^C imidazole pyridine coordination structure. The specific effect of structural optimization is to obtain better luminous efficiency and narrower luminous color purity, thereby obtaining higher quality blue phosphorescent light-emitting devices. Pyridine and phenyl have huge differences in structure and function in optoelectronic functional molecules. Among them, the tetradentate ligand Pt-C py (py is a synonym for pyridyl) coordination structure is better than Pt-C ph(ph is a synonym for phenyl) an active site with coordination function is added to the core structure, and its directed preparation is more complicated and increases the unpredictability of the preparation results. Effective preparation paths and structural data are creative prerequisites and basic conditions for property exploration. Regarding the improvement and comparison of material properties, the N^C pyrazolylpyridine coordination structure has a better effect than the N^C pyrazolphenyl coordination structure. For details, see the research papers Lu Zhu, Wentao Xie, Chunyue Qian, Wang Xie, Kang Shen, Anqi Lv, Huili Ma, Hongbo Li, Xiao-Chun Hang, *Wenqi Li, Shi-Jian Su, *and Wei Huang* Tetradentate Pt(II) Complexes for Spectrum-Stable Deep-Blueand White Electroluminescence Adv. Optical Mater. 2020, 2000406 (N^C pyrazolylpyridine coordination structure) and Huili Ma, Kang Shen, *Yipei Wu, Fang Xia, Feiling Yu, Zhengyi Sun, Chunyue Qian, Qiming Peng, Hong-Hai Zhang, Cong You, Guohua Xie, *Xiao-Chun Hang* and Wei Huang High-color-purity and efficient solution-processable bluephosphorescent light-emitting diodes with Pt(II)complexes featuring 3ππ*transitions Materials Chemistry Frontiers 2019 3 2448-2454 (N^C pyrazolephenyl coordination structure). From the perspective of energy levels, C-coordinated pyridine has stronger electronegativity and can be used to adjust the orbital energy levels of tetradentate ligand platinum complex molecules, thereby better matching the energy levels of the main materials in the device and obtaining better device effects.Regarding the changes in the electrical properties of the Pt-Cpy coordination structure, please refer to the research paper: Patrick JG Saris, Mark E. Thompson, Gram Scale Synthesis of Benzophenanthroline and Its Blue Phosphorescent Platinum Complex Org. Lett. 2016, 18, 3960. Pyridine is an electron acceptor, and in this invention, Pt-C. py The structure is presented as an electron donor in the overall molecule. This design has the characteristics of reverse application of the electrical properties of the functional group. The specific theory and its potential functional change characteristics can be referred to in the following papers: Feiling Yu, Yongjian Sheng, Dandan Wu, Ke Qin, Hongbo Li, Guohua Xie, * Qin Xue, Zhengyi Sun, Zhenzhong Lu, Huili Ma, and Xiao-Chun Hang * Blue-Phosphorescent Pt(II) Complexes of Tetradentate Pyridyl-Carbolinyl Ligands: Synthesis, Structure, Photophysics, and Electroluminescence Inorg. Chem. 2020, 59, 14493-14500. ) Summary of the invention

[0006] The present invention provides a carbene-coordinated divalent platinum complex which is suitable for use as a blue light emitter in organic light-emitting diodes (OLED), display and lighting technology.

[0007] The divalent platinum complex disclosed in the present invention has a structure described by formula (I):

[0008]

[0009] Among them, R a , R c and R d are each independently a monosubstituted or disubstituted group, and R a , R c and R d Each is independently selected from single-atom or multi-atom substitution; R b , R eEach is independently a polyatomic substituent containing at least 1 C; the monoatomic substituent includes a hydrogen atom, an isotope atom thereof or a halogen atom; the polyatomic substituent is an alkyl or aryl substituent containing 1 to 20 carbon atoms, the alkyl includes an aryl-substituted alkyl and a fluorine-substituted alkyl, the aryl includes an alkyl-substituted aryl and an aryl-substituted aryl.

[0010] Optionally, monatomic or polyatomic substituted R a , R c and R d can be independently selected from a hydrogen atom, a deuterium atom, and a fluorine atom; R a , R b , R c , R d , R e Each of the following may be independently selected from deuterated or non-deuterated methyl, benzyl, diphenylmethyl, triphenylmethyl; ethyl, 2-phenylethyl, 2,2-phenylethyl, 2,2,2-trifluoroethyl; propyl, isopropyl, 3,3,3-trifluoropropyl, 1,1,1,3,3,3-hexafluoro-2-propyl; n-butyl, isobutyl, hexafluoroisobutyl, tert-butyl; cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl; phenyl, 2-methylphenyl, 2-isopropylphenyl, 2-ethylphenyl phenyl, 2,3-dimethylphenyl, 2,3-diethylphenyl, 2,3-diisopropylphenyl, 2,3-diisobutylphenyl, 2,3-dicyclohexylphenyl, 2,3-dicyclopropylphenyl, 2,3-dicyclobutylphenyl, 2,3-dicyclopentylphenyl, 2,4-dimethylphenyl, 2,4-diethylphenyl, 2,4-diisopropylphenyl, 2,4-diisobutylphenyl, 2,4- dicyclohexylphenyl, 2,4-dicyclopropylphenyl, 2,4-dicyclobutylphenyl, 2,4-dicyclopentylphenyl, 2,6-dimethylphenyl, 2,6-diethylphenyl, 2,6-diisopropylphenyl, 2,6-diisobutylphenyl, 2,6-dicyclohexylphenyl, 2,6-dicyclopropylphenyl, 2,6-dicyclobutylphenyl, 2,6-dicyclopentylphenyl, 3,5-dimethylphenyl, 3,5-diethylphenyl, 3,5-diisopropylphenyl, 3,5-diisobutylphenyl phenyl, 3,5-dicyclohexylphenyl, 3,5-dicyclopropylphenyl, 3,5-dicyclobutylphenyl, 3,5-dicyclopentylphenyl, 2,3,5,6-tetramethylphenyl, 2,4,6-trimethylphenyl, 2,4,6-triethylphenyl, 2,4,6-triisopropylphenyl, 2,4,6-triisobutylphenyl, 2,4,6-tricyclohexylphenyl, 2,4,6-tricyclopropylphenyl, 2,4,6-tricyclobutylphenyl, 2,4,6-tricyclopentylphenyl.

[0011] Optionally, R eis a single substituent selected from alkyl, aryl-substituted alkyl, fluorine-substituted alkyl, aryl, alkyl-substituted aryl, aryl-substituted aryl or cycloalkyl.

[0012] Optionally, R a , R b , R c , R d Each is independently selected from a deuterium atom and a tritium atom.

[0013] Optionally, R a , R b , R c , R d and R e Each independently selected from the deuterated substituent -CDH 2 、-CD 2 H.-CD 3 、-CDR 1 R 2 、-CD 2 R 1 , where R 1 and R 2 Each is independently selected from alkyl, aryl-substituted alkyl, aryl, alkyl-substituted aryl, aryl-substituted aryl, cycloalkyl, cycloalkenyl, heteroaryl, alkenyl, alkynyl, amino, monoalkylamino, dialkylamino, monoarylamino, diarylamino, alkoxy, aryloxy, haloalkyl, ester, alkoxycarbonyl, amide, alkoxycarbonylamino, aryloxycarbonylamino, sulfamoyl, carbamoyl, alkylthio, urea, phosphoramido, silyl, polymer group.

[0014] Optionally, R a , R b , R c , R d and R e are each independently selected from deuterated aryl or substituted deuterated aryl-Ar-d n , wherein Ar is independently selected from aryl, aryl substituted aryl and alkyl substituted aryl; deuterium substituted hydrogen d n It can be substitution from one deuterium, substitution from multiple deuteriums, and substitution of all hydrogens by deuterium.

[0015] Optionally, the divalent platinum complex provided by the present invention has a structure selected from one of the following complexes 1 to 120:

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024] In addition, in order to illustrate the performance of divalent platinum complexes, the present invention further provides the synthesis and characterization of the luminescent physical properties of specific exemplary compounds representing the divalent platinum complexes, which are characterized by the exemplary complexes 6, 15, 17 and 120 described in detail in this specification.

[0025]

[0026] Furthermore, the present invention also provides the use of the divalent platinum complex as an electroluminescent material or a photoluminescent material.

[0027] Optionally, the divalent platinum complex is a blue light emitting material or a phosphorescent material. The blue light wavelength peak of the divalent platinum complex provided in the embodiment of the present invention is in the range of 450-470nm, and further, the blue light spectrum of the divalent platinum complex provided in the present invention is more than 50% in the range of 450-500nm.

[0028] The present invention also provides an organic optoelectronic device, comprising a light-emitting layer, wherein the light-emitting layer comprises the above-mentioned divalent platinum complex. Optionally, the divalent platinum complex is a light-emitting material, a host material or a guest material in the light-emitting layer of the organic optoelectronic device.

[0029] The beneficial effect of the present invention is that: relative to the prior art, the divalent platinum complex of the present invention provides a new blue phosphorescent luminescent material by introducing a pyridoimidazole carbene into the ligand of the divalent platinum complex. Since the carbene structure has a suitable triplet energy and the carbon-platinum coordination bond is more stable than the nitrogen-platinum coordination bond, the obtained phosphorescent material has better stability. In addition, the π system of the excited state part of the ligand increased by the pyridoimidazole structure will be able to promote the emission color and improve the performance of the device. The divalent platinum complex molecule coordinated by the neutral tetradentate ligand containing the pyridoimidazole carbene platinum structure disclosed in the present invention can emit blue light as a phosphorescent luminescent material, and has good stability, high efficiency, a narrow luminescent range and within the range of long-wavelength blue light, and is completely suitable as an organic blue light emitter in OLED-related products. In addition, the compounds provided by the present invention are easy to prepare and sublimate and purify, are soluble in general organic solvents, and can be suitable for device processes processed by evaporation and solution methods at the same time. The luminescent properties of this type of material are characterized by low energy and good color purity, which comprehensively surpasses various fluorescent materials in the prior art. It will change the situation of lack of stable and efficient blue light-doped materials in the field of flat panel displays, and at the same time achieve the effect of emitting blue light color and improving device performance; the CIE coordinates and luminescent efficiency of this type of stable complex luminescent material provided by the present invention are more in line with the requirements of flat panel displays. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a luminescence spectrum diagram of complex 6 in a specific embodiment of the present invention in solution and film;

[0031] Figure 2 is a luminescence spectrum diagram of the complex 15 in a specific embodiment of the present invention in a solution and a film;

[0032] Figure 3 is the UV-visible absorption spectrum of complex 6 in a specific embodiment of the present invention;

[0033] Figure 4 is the complex 6 in the specific embodiment of the present invention 1 H NMR spectrum;

[0034] Figure 5 is the complex 15 in the specific embodiment of the present invention 1 H NMR spectrum;

[0035] Figure 6 is a mass spectrum of complex 6 in a specific embodiment of the present invention;

[0036] Figure 7 is a mass spectrum of complex 15 in a specific embodiment of the present invention;

[0037] Figure 8 is a cross-sectional view of an OLED light-emitting device of the present invention;

[0038] Fig. 9 A schematic diagram of an OLED structure containing an EBL and a HBL layer using complex 6 in a specific embodiment of the present invention as an electroluminescent material;

[0039] Fig.10 This is a luminescence spectrum diagram of a device using complex 6 in a specific embodiment of the present invention;

[0040] Fig.11 The photoelectric conversion current efficiency diagram of the device prepared using the complex 6 of the present invention;

[0041] Fig.12 is the decay curve of the photoluminescence of complex 6 over time used in the specific embodiment of the present invention;

[0042] Fig.13 is a graph of power efficiency in photoelectric conversion of a device using complex 6 in a specific embodiment of the present invention;

[0043] Fig.14 is an external quantum efficiency diagram of a device of complex 6 in a specific embodiment of the present invention;

[0044] Fig.15 It is a luminescence attenuation diagram of the device of complex 6 in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0045] The present invention is further described below by examples and comparative examples, which are only used to illustrate the present invention, and the present invention is not limited to the following examples. Any modification or equivalent replacement of the technical solution of the present invention without departing from the scope of the technical solution of the present invention should be included in the protection scope of the present invention. The present invention can be more easily understood by referring to the following detailed description and the examples contained therein.

[0046] Compound

[0047] In some specific embodiments of the present invention, a metal platinum coordination compound (referred to as a divalent platinum complex) having a structure as shown in Formula I is provided:

[0048]

[0049] In some specific embodiments of the present invention, the provided divalent platinum complex has a structure shown in Formula II-V:

[0050]

[0051] In structural formula II, R a Represents the existence in the form of monatomic hydrogen atoms.

[0052] In structural formula III, R a It represents the presence of at least one single substituent with more than one C, and the substitution site is in the middle of the pyrazole 2 hybridized carbon atoms.

[0053] In structural formula IV, R a Represents the presence of at least two substituents R a +R a， , the substitution site is the two SP adjacent to the N atom on the pyrazole 2 hybridized carbon atoms.

[0054] In structural formula IV, R a It represents the presence of at least one single substituent with more than one C, and the substitution site is in the middle of the pyrazole 2 hybridized carbon atoms.

[0055] In structural formula V, R d Represents a SP with at least one C or more substituent, the substitution site is adjacent to the pyridine N atom 2 hybridized carbon atoms.

[0056] In structural formula VI, R d It represents the presence of a single substituent with at least one C, and the substitution site is in the middle of the benzene ring connected to the pyridine carbene. 2 Hybridized carbon atoms.

[0057] On the other hand, R b , R c and R d It can represent a monosubstituted or disubstituted substituent R b +R b， , R c +R c’ and R d +R d’ , the disubstituted substituent R 1 and R 2 It is independent of deuterium, CDH 2 , CD 2 H.CD 3 , CDR 1 R 2 , CD 2 R 1 , R 1 and R 2Each is independently selected from alkyl, aryl-substituted alkyl, fluorine-substituted alkyl, aryl, alkyl-substituted aryl, aryl-substituted aryl, cycloalkyl, cycloalkenyl, heteroaryl, alkenyl, alkynyl, amino, monoalkylamino, dialkylamino, monoarylamino, diarylamino, alkoxy, aryloxy, haloalkyl, ester, alkoxycarbonyl, amide, alkoxycarbonylamino, aryloxycarbonylamino, sulfamoyl, carbamoyl, alkylthio, urea, phosphoramido, silyl, polymer group.

[0058] In some specific representative exemplary embodiments of the present invention, Ra is selected from hydrogen atom, methyl, tert-butyl and two methyl groups; Rb is selected from hydrogen atom; Rc is selected from hydrogen atom and methyl group; Rd is selected from hydrogen atom and two methyl groups; Rd is selected from isopropyl and 2,4,6-trimethylphenyl.

[0059] In the following specific embodiments of the present invention, complex 6, complex 15, complex 17 and complex 120 are taken as examples to specifically illustrate the synthesis method, properties and performance of the divalent platinum complex provided by the present invention when used as a luminescent material, and the influence of substituents on the luminescent properties and their applications are examined.

[0060] Synthesis and purification of complexes

[0061] The various preparation methods of the compounds provided by the present invention are exemplary. These methods are used to illustrate various preparation methods, but are not intended to be limited to any specific method, and the temperature, catalyst, concentration, reactant composition and other process conditions may vary.

[0062] In CDCl 3 or DMSO-d 6 In solution, recorded by Varian liquid NMR 1 HNMR (hydrogen nuclear magnetic resonance) and 13 C NMR spectra were performed at 300, 400 or 500 MHz, and chemical shifts were based on residual protonated solvent. 3 As solvent, tetramethylsilane (δ = 0.00 ppm) was used as an internal reference to record 1 H NMR (hydrogen nuclear magnetic resonance) spectroscopy; using CDCl 3 (δ=77.00ppm) is recorded as an internal reference 13 C NMR (carbon nuclear magnetic resonance) spectroscopy. If DMSO-d 6 As solvent, residual H 2 O (δ = 3.33 ppm) was recorded as an internal reference 1 H NMR (hydrogen nuclear magnetic resonance) spectroscopy; DMSO-d 6(δ = 39.52 ppm) was recorded as an internal reference 13 C NMR (carbon nuclear magnetic resonance) spectroscopy. The following abbreviations are used to explain 1 H NMR (hydrogen nuclear magnetic resonance) multiplicity: s = singlet, d = doublet, t = triplet, q = quadruplet, p = quintet, m = multitet, br = broad.

[0063] Example 1

[0064] Preparation of complex 6

[0065] Synthesis of 3-(3,5-dimethylpyrazole)phenol:

[0066]

[0067] m-nitrophenol (556 mg, 4 mmol), intermediate 1-1 (964 mg, 4 mmol), cuprous iodide (10%), L-proline (L-Pro, 20%), cesium carbonate (2 equiv) and dimethyl sulfoxide (0.5 M) were added to a 25 ml Shrek tube. The resulting mixture was bubbled with nitrogen for 10 minutes and stirred at 120° C. for 3 days. After cooling, water and ethyl acetate (EA) were added, and the mixture was filtered. The aqueous phase was extracted with ethyl acetate, and the organic phases were combined, washed with brine, and the organic phase was washed with anhydrous Na 2 SO 4 The obtained solution was purified by silica gel chromatography using PE:EA=10:1 as the eluent to obtain intermediate 1-2 (brown viscous liquid, yield 75%).

[0068] Synthesis of intermediate 1-3:

[0069]

[0070] To a 25 ml Shrek tube, 4,4,5,5-tetramethyl-2-vinyl-1,3,2-dioxaborolane (1.16 g, 7.5 mmol), intermediate 1-2 (1.72 g, 5 mmol), tetrakis(triphenylphosphine)palladium (577.5 mg, 0.5 mmol), potassium carbonate (1.03 g, 7.5 mmol), ethylene glycol dimethyl ether (10 mL) and diH 2 O (10 mL). The resulting mixture was bubbled with nitrogen for 10 minutes and stirred at 100° C. for 24 hours. After cooling, water and ethyl acetate (EA) were added and the mixture was filtered. The aqueous phase was extracted with ethyl acetate, and the organic phases were combined, washed with brine, and the organic phase was washed with anhydrous Na 2 SO 4The obtained solution was purified by silica gel chromatography using PE:EA=10:1 as the eluent to obtain intermediate 1-3 (brown viscous liquid, yield 75%).

[0071] Synthesis of intermediate 1-4:

[0072]

[0073] To a 100 ml Shrek tube, add intermediate 1-3 (1.05 g, 3 mmol), Pd / C (100 mg), and ethanol (30 mL). The resulting mixture was replaced with hydrogen three times and stirred at room temperature for 24 hours. After cooling, water and ethyl acetate (EA) were added and the mixture was filtered. The aqueous phase was extracted with ethyl acetate, and the organic phases were combined, washed with brine, and the organic phase was washed with anhydrous Na 2 SO 4 The obtained solution was purified by silica gel chromatography using PE:EA=10:1 as the eluent to obtain intermediate 1-4 (brown viscous liquid, yield 75%).

[0074] Synthesis of intermediates 1-5

[0075]

[0076] 15 ml of acetone, 20 ml of acetic acid and 6-methyl-3-amino-2-chloropyridine (1.4 g, 10 mmol) were dissolved in 25 ml of dichloromethane. 7 ml of borane dimethyl sulfide solution (2 M) was added at 0 ° C, and then stirred at room temperature overnight. After the reaction was complete, 25 wt% ammonia solution was added to adjust the pH to 8. After adding 50 ml of water, it was extracted three times with dichloromethane. The organic phase was collected and dried with anhydrous sodium sulfate, and the crude product of intermediate 1-5 was directly used in the next step (yellow oil, yield 95%).

[0077] Synthesis of pyridinediamine derivatives 1-6:

[0078]

[0079] Into a sealed tube in a glove box, intermediate 1-4 (1 equiv), intermediate 1-5 (1.1 equiv), tris(dibenzylideneacetone)dipalladium (5%), 1,1'-binaphthyl-2,2'-bisdiphenylphosphine (5%), sodium tert-butoxide (1.5 equiv) and toluene (0.2 M) were added. After bubbling the mixture for 15 minutes, the mixture was heated at 130°C for 20 hours. After cooling, ethyl acetate was added, and the mixture was filtered. The aqueous phase was extracted with ethyl acetate, and the organic phases were mixed, washed with brine, and washed with anhydrous Na 2 SO 4The obtained solution was purified by silica gel chromatography using PE:EA=6:1 as the eluent, and the eluent was spin-dried to obtain intermediate 1-6 (yellow viscous liquid, yield 90%).

[0080] Synthesis of carbene hexafluorophosphate 1-7:

[0081]

[0082] Add intermediate 1-6 (1 equiv), ammonium hexafluorophosphate (1.1 equiv) and triethyl orthoformate (0.5 M) to a sealed tube and heat at 120°C overnight. After cooling to room temperature, add ethyl acetate to precipitate a yellow precipitate, which is filtered to obtain intermediate 1-7 (yellow solid, yield 60%).

[0083] Synthesis of complexes:

[0084]

[0085] Add intermediate 1-7 (1 equiv), dichloro(1,5-cyclooctadiene)platinum(II) (Pt(COD)Cl 2 ,0.9equiv), sodium acetate (1.05equiv) and THF (0.5M). Heat at 120°C for 3 days. Cool to room temperature and spin dry. Use DCM∶PE=2∶1 as eluent and purify the obtained solution by silica gel chromatography to obtain the target product: complex 6 (yellow powder, yield 70%). NMR (400MHz, CDCl 3 )δ8.53(d,J=7.6Hz,1H),7.78(d,J=8.0Hz,1H),7.31-7.26(m,1H),7.23-7.21(m,1H),7.08(d,J=8.4Hz,1H),7.01(s,1H),6.20(s,1H),5.2 5-5.21(m,1H),3.19-3.12(m,1H),2.76(s,3H),2.71(s,3H),2.60(s,3H),1.68(d,J=6.8Hz,6H),1.37(d,J=6.8Hz,6H).MS(ESI):673.9[M] + .The emission peak in dichloromethane (DCM) solution is 466nm, and the half-maximum width (FWHM) is 44nm. The emission peak in polymethyl methacrylate (PMMA) film is 466nm, and FWHM is 49nm.

[0086] Example 2

[0087] Preparation of complex 15

[0088] Synthesis of pyridinediamine derivative 2-1:

[0089]

[0090] Into a sealed tube in a glove box, intermediate 1-4 (1 equiv), 2-chloro-N-(2,6-diisopropylphenyl)-6-methylpyridin-3-amine (1.1 equiv), tris(dibenzylideneacetone)dipalladium (5%), 1,1'-binaphthyl-2,2'-bisdiphenylphosphine (5%), sodium tert-butoxide (1.5 equiv) and toluene (0.2 M) were added. After bubbling the mixture for 15 minutes, the mixture was heated at 130°C for 20 hours. After cooling, ethyl acetate was added, and the mixture was filtered. The aqueous phase was extracted with ethyl acetate, and the organic phases were mixed, washed with brine, and washed with anhydrous Na 2 SO 4 The obtained solution was purified by silica gel chromatography using PE:EA=6:1 as the eluent, and the eluent was spin-dried to obtain intermediate 2-1 (yellow viscous liquid, yield 90%).

[0091] Synthesis of carbene hexafluorophosphate 2-2:

[0092]

[0093] Add intermediate 2-1 equiv), ammonium hexafluorophosphate (1.1 equiv) and triethyl orthoformate (0.5 M) to a sealed tube and heat at 120°C overnight. After cooling to room temperature, add ethyl acetate to precipitate a yellow precipitate, which is filtered to obtain intermediate 2-2 (yellow solid, yield 60%).

[0094] Synthesis of complexes:

[0095]

[0096] Add intermediate 2-2 (1 equiv), dichloro(1,5-cyclooctadiene)platinum(II) (Pt(COD)Cl 2 ,0.9equiv), sodium acetate (1.05equiv) and THF (0.5M). Heat at 120°C for 3 days. Cool to room temperature and spin dry. Use DCM:PE=2:1 as eluent and purify the obtained solution by silica gel chromatography to obtain the target product: complex 15 (yellow powder, yield 70%)

[0097] NMR (400MHz, CDCl 3)δ8.76(d,J=7.6,1H),7.56(t,J=7.6Hz,1H),7.37-7.35(m,3H),7.30-7.28(m,1H),7.03(q,J=8.4Hz,2H),6.97(s,1H),5.87(s,1H),3.11- 3.01(m,3H),3.04(m,3H),2.74(s,3H),2.68(s,3H),1.36(d,J=6.8Hz,6H),0.95(d,J=6.8Hz,6H),0.88(d,J=6.8Hz,6H).MS(ESI):791.9[M] + .The emission peak in dichloromethane (DCM) solution is 466nm, and the half-maximum width (FWHM) is 23nm. The emission peak in polymethyl methacrylate (PMMA) film is 468nm, and FWHM is 45nm.

[0098] Implementation Example 3

[0099] Preparation of complex 118

[0100] Synthesis of intermediate 1-3:

[0101]

[0102] To a 25 ml Shrek tube, 2,4,6-trimethylphenylboronic acid (1.23 g, 7.5 mmol), intermediate 1-2 (1.72 g, 5 mmol), tetrakis(triphenylphosphine)palladium (577.5 mg, 0.5 mmol), potassium carbonate (1.03 g, 7.5 mmol), ethylene glycol dimethyl ether (10 mL) and diH 2 O (10 mL). The resulting mixture was bubbled with nitrogen for 10 minutes and stirred at 100° C. for 24 hours. After cooling, water and ethyl acetate (EA) were added and the mixture was filtered. The aqueous phase was extracted with ethyl acetate, and the organic phases were combined, washed with brine, and the organic phase was washed with anhydrous Na 2 SO 4 The obtained solution was purified by silica gel chromatography using PE:EA=10:1 as the eluent to obtain intermediate 3-1 (brown viscous liquid, yield 75%).

[0103] Synthesis of intermediate 3-2:

[0104]

[0105] To a 100 ml Shrek tube, add intermediate 3-1 (1.05 g, 3 mmol), Pd / C (100 mg), and ethanol (30 mL). The resulting mixture was replaced with hydrogen three times and stirred at room temperature for 24 hours. After cooling, water and ethyl acetate (EA) were added and the mixture was filtered. The aqueous phase was extracted with ethyl acetate, and the organic phases were combined, washed with brine, and the organic phase was washed with anhydrous Na 2 SO 4 The obtained solution was purified by silica gel chromatography using PE:EA=10:1 as the eluent to obtain intermediate 3-2 (brown viscous liquid, yield 75%).

[0106] Synthesis of intermediate 3-3

[0107]

[0108] Into a sealed tube in a glove box, intermediate 3-2 (1 equiv), intermediate 1-5 (1.1 equiv), tris(dibenzylideneacetone)dipalladium (5%), 1,1'-binaphthyl-2,2'-bisdiphenylphosphine (5%), sodium tert-butoxide (1.5 equiv) and toluene (0.2 M) were added. After bubbling the mixture for 15 minutes, the mixture was heated at 130°C for 20 hours. After cooling, ethyl acetate was added, and the mixture was filtered. The aqueous phase was extracted with ethyl acetate, and the organic phases were mixed, washed with brine, and washed with anhydrous Na 2 SO 4 The obtained solution was purified by silica gel chromatography using PE:EA=6:1 as the eluent, and the eluent was spin-dried to obtain intermediate 3-3 (yellow viscous liquid, yield 90%).

[0109] Synthesis of carbene hexafluorophosphate 3-4:

[0110]

[0111] Add intermediate 3-3 (1 equiv), ammonium hexafluorophosphate (1.1 equiv) and triethyl orthoformate (0.5 M) to a sealed tube and heat at 120°C overnight. After cooling to room temperature, add ethyl acetate to precipitate a yellow precipitate, which is filtered to obtain intermediate 3-4 (yellow solid, yield 60%).

[0112] Synthesis of complexes:

[0113]

[0114] Add intermediate 3-4 (1 equiv), dichloro(1,5-cyclooctadiene)platinum(II) (Pt(COD)Cl 2,0.9equiv), sodium acetate (1.05equiv) and THF (0.5M). Heat at 120°C for 3 days. Cool to room temperature and spin dry. Use DCM∶PE=2∶1 as eluent and purify the obtained solution by silica gel chromatography to obtain the target product: complex 120 (yellow powder, yield 70%). MS (ESI): 750.3[M] + .The emission peak in dichloromethane (DCM) solution is 468nm, and the half-maximum width (FWHM) is 44nm. The emission peak in polymethyl methacrylate (PMMA) film is 468nm, and FWHM is 44nm.

[0115] Implementation Example 4

[0116] Preparation of complex 17

[0117] Synthesis of 2-chloro-6-(3-nitrophenoxy)-4-(1H-pyrazol-1-yl)pyridine:

[0118]

[0119] m-nitrophenol (556 mg, 4 mmol), intermediate 4-1 (848 mg, 4 mmol), cuprous iodide (10%), L-proline (L-Pro, 20%), cesium carbonate (2 equiv) and dimethyl sulfoxide (0.5 M) were added to a 25 ml Shrek tube. The resulting mixture was bubbled with nitrogen for 10 minutes and stirred at 120° C. for 3 days. After cooling, water and ethyl acetate (EA) were added, and the mixture was filtered. The aqueous phase was extracted with ethyl acetate, and the organic phases were combined, washed with brine, and the organic phase was washed with anhydrous Na 2 SO 4 The obtained solution was purified by silica gel chromatography using PE:EA=10:1 as the eluent to obtain intermediate 4-2 (brown viscous liquid, yield 75%).

[0120] Synthesis of intermediate 4-3:

[0121]

[0122] To a 25 ml Shrek tube, 4,4,5,5-tetramethyl-2-vinyl-1,3,2-dioxaborolane (1.16 g, 7.5 mmol), intermediate 4-2 (1.58 g, 5 mmol), tetrakis(triphenylphosphine)palladium (577.5 mg, 0.5 mmol), potassium carbonate (1.03 g, 7.5 mmol), ethylene glycol dimethyl ether (10 mL) and diH 2O (10 mL). The resulting mixture was bubbled with nitrogen for 10 minutes and stirred at 100° C. for 24 hours. After cooling, water and ethyl acetate (EA) were added and the mixture was filtered. The aqueous phase was extracted with ethyl acetate, and the organic phases were combined, washed with brine, and the organic phase was washed with anhydrous Na 2 SO 4 The obtained solution was purified by silica gel chromatography using PE:EA=10:1 as the eluent to obtain intermediate 4-3 (brown viscous liquid, yield 75%).

[0123] Synthesis of intermediate 4-4:

[0124]

[0125] To a 100 ml Shrek tube, add intermediate 4-3 (1.05 g, 3 mmol), Pd / C (100 mg), and ethanol (30 mL). The resulting mixture was replaced with hydrogen three times and stirred at room temperature for 24 hours. After cooling, water and ethyl acetate (EA) were added and the mixture was filtered. The aqueous phase was extracted with ethyl acetate, and the organic phases were combined, washed with brine, and the organic phase was washed with anhydrous Na 2 SO 4 The obtained solution was purified by silica gel chromatography using PE:EA=10:1 as the eluent to obtain intermediate 4-4 (brown viscous liquid, yield 75%).

[0126] Synthesis of pyridinediamine derivatives 4-5:

[0127]

[0128] Into a sealed tube in a glove box, intermediate 4-4 (1 equiv), intermediate 1-5 (1.1 equiv), tris(dibenzylideneacetone)dipalladium (5%), 1,1'-binaphthyl-2,2'-bisdiphenylphosphine (5%), sodium tert-butoxide (1.5 equiv) and toluene (0.2 M) were added. After bubbling the mixture for 15 minutes, the mixture was heated at 130°C for 20 hours. After cooling, ethyl acetate was added, and the mixture was filtered. The aqueous phase was extracted with ethyl acetate, and the organic phases were mixed, washed with brine, and washed with anhydrous Na 2 SO 4 The obtained solution was purified by silica gel chromatography using PE:EA=6:1 as the eluent, and the eluent was spin-dried to obtain intermediate 4-5 (yellow viscous liquid, yield 90%).

[0129] Synthesis of carbene hexafluorophosphate 4-6:

[0130]

[0131] Add intermediate 4-5 (1 equiv), ammonium hexafluorophosphate (1.1 equiv) and triethyl orthoformate (0.5 M) to a sealed tube and heat at 120°C overnight. After cooling to room temperature, add ethyl acetate to precipitate a yellow precipitate, which is filtered to obtain intermediate 4-6 (yellow solid, yield 60%).

[0132] Synthesis of complexes:

[0133]

[0134] Add intermediate 4-6 (1 equiv), dichloro(1,5-cyclooctadiene)platinum(II) (Pt(COD)Cl 2 ,0.9equiv), sodium acetate (1.05equiv) and THF (0.5M). Heat at 120°C for 3 days. Cool to room temperature and spin dry. Use DCM:PE=2:1 as eluent and purify the obtained solution by silica gel chromatography to obtain the target product: complex 17 (yellow powder, yield 70%)

[0135] MS(ESI):646.2[M] + .The emission peak in dichloromethane (DCM) solution is 467nm, and the half-maximum width (FWHM) is 45nm. The emission peak in polymethyl methacrylate (PMMA) film is 467nm, and FWHM is 46nm.

[0136] Characterization of photophysical properties of compounds

[0137] The embodiments of the present invention also provide the use of the divalent platinum complex as an electroluminescent material or a photoluminescent material.

[0138] Optionally, the divalent platinum complex is a blue light emitting material or a phosphorescent light emitting material. The blue light wavelength peak of the divalent platinum complex provided in the embodiment of the present invention is in the range of 450 to 470 nm, and further, the blue light spectrum of the divalent platinum complex provided in the embodiment of the present invention is more than 50% in the range of 450 to 490 nm.

[0139] Explanation of English terms in the chart: Intensity intensity; PL luminescence spectrum; PL Retention luminescence retention; Normalized normalization; CE current efficiency; PE energy efficiency;

[0140] Attached Figure 1-2The luminescence spectra of divalent platinum complexes 6 and 15 in solution and film are shown respectively; under 340nm ultraviolet light excitation, the luminescence wavelengths of the three complexes in dichloromethane solution are between 450-480nm, and the luminescence wavelengths in polymethyl methacrylate (PMMA) are between 450-480nm. The wavelengths of all complexes are in the deep blue light region, and the half-peak width of the spectrum is narrow, indicating that this series of complexes are good blue luminescent materials.

[0141] Attached Figure 4 The 1H NMR spectrum of a single molecule of complex 6 shows that the complex can exist independently and stably and can be separated, purified and characterized. From the NMR spectrum, in addition to the stable structural characterization of the divalent platinum complex, the divalent platinum complex does not show any signal of aggregation, indicating that this type of divalent platinum complex molecules exist in a single molecule isolated state in the solution state.

[0142] Attached Figure 5 The 1H NMR spectrum of a single molecule of complex 15 shows that the complex can exist independently and stably and can be separated, purified and characterized. From the NMR spectrum, in addition to the stable structural characterization of the divalent platinum complex, the divalent platinum complex does not show any signal of aggregation, indicating that this type of divalent platinum complex molecules exist in a single molecule isolated state in the solution state.

[0143] Attached Figure 6 The mass spectrometry characterization diagram of the molecule of complex 6. The mass spectrometry molecule shows that the molecular signal shows an M / C peak of 632.4, which is consistent with the molecular ion peak of compound 6, indicating that the structure of the complex is the designed structure.

[0144] Figure 7 It is the mass spectrometer of the complex 15 in the specific embodiment of the present invention: the mass spectrometer molecular display molecular signal shows that the M / C peak is 792.2, which is consistent with the molecular ion peak of compound 15, indicating that the structure of the complex is the designed structure.

[0145] The optical properties of the divalent platinum carbene complex of the present invention were tested. Representative data of the color purity of the emitter can be obtained from the emission spectra of the dichloromethane (DCM) solution of the complex and the polymethyl methacrylate (PMMA) film; the test results are shown in Table 1.

[0146] Table 1 Emission spectrum data of complexes

[0147]

[0148] As shown in Table 1, the peak wavelength of the complex of the present invention is between 450-470 nm, the half-peak width of the solution is above 20-50 nm, and the photoluminescence efficiency is above 50%, indicating that the divalent platinum carbene complex with the general formula I structure is a high-efficiency narrow-band green phosphorescent luminescent material.

[0149] Attached Figure 8 A cross-sectional view of an OLED light-emitting device 1000 is shown, and the OLED device can use the platinum complex described in this article as a light-emitting material. The OLED device 1000 includes a substrate 1002, an anode layer 1004, a hole transport layer 1006, a light-emitting layer 1008, an electron transport layer 1010, and a metal cathode layer 1012. The anode 1004 is generally a transparent material, such as indium tin oxide. The light-emitting layer 1008 can be a light-emitting material including an emitter and a host. Wherein EIL refers to an electron injection layer, which can be regarded as a part of the electron transport layer 1010. HIL is a hole injection layer, which can be regarded as a part of the hole transport layer 1006. CPL is a cathode cover layer. The complex 47 disclosed in this article is used in the light-emitting layer 1008 as a blue light-emitting doping material.

[0150] In the above specific embodiments, the light-emitting layer 1008 may include one or more platinum complexes provided by the present invention, optionally with a host material. The ETL layer 1010 and the HTL 1006 may also include one or more platinum complexes and another injection layer close to the electrode. The materials of the injection layer may include an EIL (electron injection layer), a HIL (hole injection layer) and a CPL (cathode cover layer), which may be in the form of a single layer or dispersed in an electron or hole transport material. The host material may be any suitable host material known in the art. The luminous color of the OLED is determined by the luminous energy (optical energy gap) of the light-emitting layer 1008 material, and the luminous energy (optical energy gap) of the light-emitting layer 1008 material can be tuned by tuning the electronic structure of the emitting platinum complex and / or the host material as described above. The hole transport material in the HTL layer 1006 and the electron transport material in the ETL layer 1010 may include any suitable hole transporter known in the art.

[0151] The complex 6 is doped into the main material as a light-emitting material to prepare an OLED device. The OLED device structure can be Figure 8 On the basis of the charge blocking layer, such as the hole blocking layer HBL and the electron blocking layer EBL, the efficiency of the device is improved. Fig. 9The device structure shown is ITO / HATCN / HTL / EBL / host material: platinum complex / HBL / ET / metal electrode. BD refers to the blue light doping material, that is, the platinum complex of the present invention. In addition, the complex of the present invention can also be used in the following common device structures: ITO / HATCN (10nm) / NPD (40nm) / TAPC (10nm) / 2,6-mCPy: platinum complex / DPPS (40nm) / LiF / Al; ITO / HATCN (10nm) / NPD (40nm) / mCBP: platinum complex / BAlq (10nm) / Alq 3 (30nm) / LiF / Al; ITO / HATCN(10nm) / NPD(40nm) / TAPC(10nm) / host material: platinum complex / DPPS(40nm) / BmPyPB orTmPyPB / LiF / Al; ITO / HATCN(10nm) / HTL / EBL / bipolar host material: divalent platinum complex / bipolar host material / BmPyPB or TmPyPB / LiF / Al; platinum complex / DPPS(40nm) / BmPyPB or TmPyPB / LiF / Al; ITO / HATCN(10nm) / NPD(40nm) / TrisPCz(10nm) / mCBP: platinum complex (25nm) / Balq(10nm)or mCBT(8nm) / BPyTP(40nm) / LiF / Al, etc. Fig. 9 This is one of the schematic diagrams of the OLED structure containing EBL and HBL layers using the complex 6 of the present invention as the electroluminescent material. By adding a barrier layer, the charge utilization rate and luminous efficiency can be improved, and the stability of the device can also be increased.

[0152] Among the above materials, HATCN (2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylenehexacabonitrile);

[0153] NPD (N,N'-Bis-(1-naphthalenyl)-N,N'-bis-phenyl-(1,1'-biphenyl)-4,4'-diamine)

[0154] TAPC 4,4′-cyclohexylbis[N,N-bis(4-methylphenyl)aniline]4,4′-cyclohexylidenebis[N,N-bis(p-tolyl)aniline]

[0155] 2,6mCPy 2,6-Di(9H-carbazol-9-yl)pyridine

[0156] DPPSDiphenylbis(4-(pyridin-3-yl)phenyl)silane

[0157] mCBP 3,3'-Di(9H-carbazol-9-yl)-1,1'-biphenyl (purified by sublimation)

[0158] BAlqBis(2-Methyl-8-quinolinolato-N1,O8)-(1,1'-biphenyl-4-olato)aluMinuM

[0159] Alq 3 8-Hydroxyquinoline aluminum salt

[0160] BmPyPB 1,3-bis[3,5-di(pyridin-3-yl)phenyl]benzene

[0161] TmPyPB 1,3,5-tri[(3-pyridyl)-phen-3-yl]benzene3,3'-[5'-[3-(3-pyridyl)phenyl][1,1':3',1"-terphenyl]-3,3"-diyl]bipyridine

[0162] TrisPCz 9,9′,9”-Triphenyl-3,3′:6′,3”-Tri-9H-carbazole

[0163] BPyTP 2,7-Di(2,2'-bipyridin-5-yl)triphenylene

[0164] Attached Fig.10The luminescence spectrum of the device using platinum complex 6 is shown. The blue light with the structure of ITO / HATCN (10nm) / NPD (40nm) / TAPC (10nm) / 2,6-mCPy: 5% complex 6 (25nm) / 2,6-mCPy (10nm) / TmPyPB (30nm) / LiF (1nm) / Al (100nm) is used. According to the electroluminescence spectrum of the device with 5% complex doped in the luminescent layer, the luminescence peak is 3nm red-shifted relative to its photoluminescence peak in the PMMA medium, and the half-peak width is equivalent, maintaining the luminescence characteristics of the luminescent complex 6 itself. The chromaticity coordinate value calculated is CIE (0.15, 0.18), indicating that this device is suitable for use as a deep blue light emitting device. According to the normalized integral, only 14.5% of the stimulating blue light components less than 450nm, and 70.2% of the photon energy is above 500nm. According to traditional blue light attribution, blue light photons between 450 and 500 nm account for 55.7% of all emitted photons.

[0165] Attached Fig.11 is a diagram of the photoelectric conversion current efficiency of a device prepared using the complex 6 of the present invention, Fig.11 It can be seen that the current efficiency of the device prepared using complex 6 is higher. The device structure is ITO / HATCN (10nm) / NPD (40nm) / TAPC (10nm) / 2,6-mCPy: 5% complex 6 (25nm) / 2,6-mCPy (10nm) / TmPyPB (30nm) / LiF (1nm) / Al (100nm). Fig.11 The photoelectric conversion current efficiency of the device using complex 6 was shown to be very stable, from 0mA / cm 2 Up to 20mA / cm 2 Under the change of current density, the current roll-off is less than 10%, and the device of the doped material has a high efficiency. The device is at 10mA / cm 2 The current efficiency is 12.3 cd / A, indicating that complex 6 has efficient and stable luminescent light conversion performance as a blue light emitting doping material.

[0166] Fig.12 This is the decay curve of the photoluminescence of complex 6 over time. Figure 5 The luminescence intensity of a 5wt% doped polystyrene (PS) film using complex 6 changes with time under 375nm UV light irradiation, indicating that the device using complex 2 can maintain a decay of no more than 3% under strong luminescence conditions for 60 minutes, and the spectral decay within 6 hours is less than 10%. This experiment shows that the complex has excellent luminescence stability. This decay test is performed by 50mW / m 2The stable polystyrene polymer film doped with 5% of the material was irradiated with ultraviolet light, and the intensity of photoluminescence was recorded, and finally the functional relationship between the luminescence decay of the compound and time was obtained. Fig.13 It shows that complex 6 has good luminescence stability.

[0167] Fig.13 The power efficiency of the device using complex 6 in photoelectric conversion is shown. The device structure is ITO / HATCN (10nm) / NPD (40nm) / TAPC (10nm) / 2,6-mCPy: 5% complex 6 (25nm) / 2,6-mCPy (10nm) / TmPyPB (30nm) / LiF (1nm) / Al (100nm). Complex 6 accounts for 5% of the light-emitting layer material. The device has a power efficiency of 1147cd / m 2 The brightness is 9lm / W, indicating that complex 6 has efficient and stable luminescent light conversion performance as a blue light emitting doping material.

[0168] Fig.14 The EQE diagram of the device prepared using the complex 6 shown in the present invention, the device structure is: ITO / TmPyPB (30nm) / 2,6-mCPy: 5% complex 6 (25nm) / 2,6-mCPy (10nm) / TmPyPB (30nm) / LiF (1nm) / Al (100nm). It can be seen from the figure that the EQE of the device prepared by complex 6 is relatively high, indicating that the device performance of complex 6 is good and it is an excellent OLED material.

[0169] Fig.15 The electroluminescence decay curve of the device prepared using the complex 6 of the present invention over time. The device structure is ITO / HATCN (10nm) / NPD (40nm) / TAPC (10nm) / 2,6-mCPy: 5% complex 6 (25nm) / 2,6-mCPy (10nm) / TmPyPB (30nm) / LiF (1nm) / Al (100nm). LT50@50mA / cm 2 The lifespan is 22.6h respectively.

[0170] The performance data of the light-emitting device prepared using the above platinum complex are shown in Table 2.

[0171] Table 2 Device luminescence performance

[0172]

[0173] As shown in Table 2, the luminescence performance data of the light-emitting devices prepared by various platinum complexes are compared. The electroluminescence wavelength of the light-emitting device is mainly determined by the photoluminescence of the platinum complex itself, and the purity of the photoluminescence spectrum of the platinum complex itself is directly related to the spectral purity of the electroluminescence. Under the same conditions, the efficiency of the light-emitting device is also consistent with the trend of the luminescence quantum efficiency of the platinum complex itself, and the color purity of the light emitted by the light-emitting device is directly related to the spectral color purity of the light emitted under the light excitation of the doping material itself. Comparison of the electroluminescence spectrum of the platinum complex light-emitting device and the photoluminescent device in the thin film shows that compared with the photoluminescence spectrum of the thin film, the electroluminescence spectrum of the light-emitting device is slightly red-shifted, but the peak wavelength is still in the blue light region (450-470nm), and most of the spectrum is also in the blue light range. The calculated chromaticity coordinates show that the light-emitting device belongs to a pure blue light-emitting device. Since most of the light is in the blue light range, only a small amount of long-wavelength light needs to be filtered out, which means that the platinum compound material provided by the embodiment of the present invention can fully meet the chromaticity requirements of high-efficiency pure blue light CIE (0.14, 0.08) devices in displays.

[0174] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present invention, and in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A divalent platinum complex, characterized in that It has the structure shown in formula I: in, R a , R c and R d are each independently a monosubstituted or disubstituted group, and R a , R c and R d are each independently selected from monatomic or polyatomic substitution; R b , R e Each is independently a polyatomic substituent containing at least 1 C; The monoatomic substituent includes a hydrogen atom, an isotope atom thereof or a halogen atom; The polyatomic substituent is an alkyl or aryl substituent containing 1 to 20 carbon atoms. The alkyl group includes an aryl-substituted alkyl group and a fluorine-substituted alkyl group. The aryl group includes an alkyl-substituted aryl group.

2. The divalent platinum complex according to claim 1, characterized in that R substituted with a single or multiple atom a , R c and R d can be independently selected from a hydrogen atom, a deuterium atom, and a fluorine atom; R a , R b , R c , R d , R e Each of the following may be independently selected from deuterated or non-deuterated methyl, benzyl, diphenylmethyl, triphenylmethyl; ethyl, 2-phenylethyl, 2,2-phenylethyl, 2,2,2-trifluoroethyl; propyl, isopropyl, 3,3,3-trifluoropropyl, 1,1,1,3,3,3-hexafluoro-2-propyl; n-butyl, isobutyl, hexafluoroisobutyl, tert-butyl; cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl; phenyl, 2-methylphenyl, 2-isopropylphenyl, 2-ethylphenyl phenyl, 2,3-dimethylphenyl, 2,3-diethylphenyl, 2,3-diisopropylphenyl, 2,3-diisobutylphenyl, 2,3-dicyclohexylphenyl, 2,3-dicyclopropylphenyl, 2,3-dicyclobutylphenyl, 2,3-dicyclopentylphenyl, 2,4-dimethylphenyl, 2,4-diethylphenyl, 2,4-diisopropylphenyl, 2,4-diisobutylphenyl, 2,4- dicyclohexylphenyl, 2,4-dicyclopropylphenyl, 2,4-dicyclobutylphenyl, 2,4-dicyclopentylphenyl, 2,6-dimethylphenyl, 2,6-diethylphenyl, 2,6-diisopropylphenyl, 2,6-diisobutylphenyl, 2,6-dicyclohexylphenyl, 2,6-dicyclopropylphenyl, 2,6-dicyclobutylphenyl, 2,6-dicyclopentylphenyl, 3,5-dimethylphenyl, 3,5-diethylphenyl, 3,5-diisopropylphenyl, 3,5-diisobutylphenyl phenyl, 3,5-dicyclohexylphenyl, 3,5-dicyclopropylphenyl, 3,5-dicyclobutylphenyl, 3,5-dicyclopentylphenyl, 2,3,5,6-tetramethylphenyl, 2,4,6-trimethylphenyl, 2,4,6-triethylphenyl, 2,4,6-triisopropylphenyl, 2,4,6-triisobutylphenyl, 2,4,6-tricyclohexylphenyl, 2,4,6-tricyclopropylphenyl, 2,4,6-tricyclobutylphenyl, 2,4,6-tricyclopentylphenyl.

3. The divalent platinum complex according to claim 1, characterized in that It has a structure selected from one of the following complexes 1 to 120:

4. The divalent platinum complex according to any one of claims 1 to 3 is used as a blue light emitting material or a blue phosphorescent light emitting material, and can also be used as an electroluminescent material or a photoluminescent material.

5. An organic optoelectronic device, characterized in that: The invention comprises a light-emitting layer, wherein the light-emitting layer comprises the divalent platinum complex according to any one of claims 1 to 3.

6. The organic optoelectronic device according to claim 5, characterized in that: The divalent platinum complex can be used as a light-emitting material, a host material, a guest material or other auxiliary functional materials in the organic optoelectronic device.

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