Spirofluorene-biphenyl-acridine-based tetradentate fused-ring 6 / 5 / 6 platinum(II) complex phosphorescent luminescent material and its application

Abstract

The present invention belongs to the technical field of organic optoelectronic materials, and particularly relates to the field of phosphorescent luminescent materials of tetradentate 6 / 5 / 6 metal fused-ring platinum(II) complexes. A green phosphorescent tetradentate 6 / 5 / 6 metal fused-ring platinum(II) complex based on spirofluorene-biphenyl-acridine, a preparation method thereof, and applications thereof are disclosed, and can be used in the fields of OLED display and lighting. The tetradentate cyclometalated platinum(II) complex has a structure shown in general formula (I). The phosphorescent complex provided by the present invention can increase the steric hindrance of the planar platinum(II) complex molecule through the spirofluorene group in the molecular structure, reduce the π-π stacking between molecules, thereby weakening the interaction between phosphorescent molecules and facilitating the sublimation and purification of material molecules; at the same time, it can weaken the triplet-triplet quenching between excited state molecules, which is beneficial to the improvement of the quantum efficiency of the material.

Description

Technical Field

[0001] The present invention belongs to the technical field of organic optoelectronic materials, and particularly relates to a phosphorescent material based on a tetradentate fused-ring 6 / 5 / 6 platinum(II) complex of spirofluorene-biphenyl-acridine, which can be used in the fields of OLED display and lighting. Background Art

[0002] Organic light-emitting diodes (OLEDs) are a new generation of self-luminous display technologies. Compared with the previous generation of liquid crystal displays (LCDs), this technology has many excellent properties, such as ultra-thin and light, low power consumption, high contrast, wide color gamut, and can achieve flexible and transparent displays. After more than thirty years of development, this technology has made great progress and has been widely used in small and medium-sized display products such as smart phones, wearable devices, and in-vehicle displays. It can be foreseen that OLED display is gradually becoming the mainstream trend of energy-saving lighting and new display technologies.

[0003] In the entire industrial chain of OLED display, organic light-emitting materials always play a crucial role and are one of the fields with the highest technical barriers.

[0004] In 1998, S.R. Forrest et al. found through research that transition metal organic metal complexes such as Ir, Pt, and Ru can achieve rapid intersystem crossing (ISC) and long-lived phosphorescence decay due to their strong spin-orbit coupling (SOC). Using transition metal phosphorescent complexes as the light-emitting materials for OLEDs, since they can capture both singlet and triplet excitons simultaneously, the internal quantum efficiency of OLEDs can reach 100% theoretically, greatly improving the light-emitting efficiency of the light-emitting device. In particular, in the application of OLED light-emitting materials, Pt(II) complexes are considered as substitutes for common phosphorescent iridium complexes. Platinum complexes have the characteristics of high light-emitting efficiency, short excited state lifetime (η), and adjustable emission color, and are one of the most promising materials for preparing efficient OLEDs. However, further designing new ligands and developing highly efficient light-emitting platinum complexes still have extremely important scientific research value and economic value for realizing full-color OLED display lighting.

[0005] Research has shown that Pt(II) complexes containing acridine groups have excellent photophysical and chemical stabilities. However, due to their planar quadrilateral structure, they are prone to form π-π stacking and platinum-platinum interactions, resulting in triplet annihilation and reducing the light-emitting efficiency of the complex. This limits its application scope in the field of light emission. Therefore, it is of great value to rationally design the structure of the ligand and develop rigid and sterically hindered light-emitting molecules to prevent intermolecular interactions.

[0006] A tetradentate metal fused-ring structure based on spirofluorene-biphenyl-acridine was designed. Since the bridging atoms are carbon atoms based on the spirofluorene structure, the rigidity of the molecule is further improved, which can effectively inhibit the rotation and vibration of ligand molecules, thereby effectively improving the emission quantum efficiency of the material. SUMMARY OF THE INVENTION

[0007] In view of the deficiencies of the above-mentioned prior art, the purpose of the present invention is to provide a tetradentate fused-ring 6 / 5 / 6 metal platinum (II) complex phosphorescent material based on spirofluorene-biphenyl-acridine, its preparation method and application. The organic light-emitting material is based on a tetradentate ligand of spirofluorene-biphenyl-acridine, aiming to provide a new metal platinum (II) complex phosphorescent material to solve the problems of scarcity and low efficiency of existing light-emitting materials. The light-emitting material can be used in the fields of OLED display and lighting.

[0008] To achieve the above purpose, in the first aspect, an embodiment of the present invention provides a tetradentate fused-ring 6 / 5 / 6 metal platinum (II) complex based on spirofluorene-biphenyl-acridine, characterized in that the tetradentate cyclometalated platinum (II) complex phosphorescent material has the structure shown in general formula (I):

[0009]

[0010] Wherein:

[0011] M = metal Pt or Pd;

[0012] V 1 is independently selected from S atom, N atom, CR a R b ;

[0013] Y 1 、Y 2 、Y 3 、Y 4 、Y 5 、Y 6 、Y 7 、Y 8 、Y 9 、Y 10 、Y 11 and Y 12 are each independently selected from N atom, CH group;

[0014] R 1 、R 2 、R 3 、R 4 、R 5 、R 6 and R 7 each independently represents mono-substitution, di-substitution, tri-substitution, tetra-substitution or no substitution, and R 1 、R2 , R 3 , R 4 , R 5 , R 6 and R 7 Each independently is hydrogen, deuterium, aryl, cycloalkyl, cycloalkenyl, heterocyclic group, heteroaryl, alkyl, alkenyl, alkynyl, halogen, hydroxyl, mercapto, nitro, cyano, amino, mono- or di-alkylamino, mono- or di-arylamino, alkoxy, aryloxy, haloalkyl, ester group, nitrile group, isonitrile group, heteroaryl, alkoxycarbonyl, acylamino, alkoxycarbonylamino, aryloxycarbonylamino, sulfonylamino, sulfamoyl, carbamoyl, alkylthio, sulfinyl, ureido, phosphoramido, imino, sulfo, carboxyl, hydrazino, alkyl- or aryl-silyl, or a combination thereof; and two or more adjacent R 1 , R 2 , R 3 , R 4 , R 5 , R 6 and R 7 Each independently or optionally connect to form a fused ring.

[0015] Furthermore, the spirofluorene-biphenyl-acridine-based tetradentate fused-ring 6 / 5 / 6 metal platinum (II) complex, optionally, the tetradentate fused-ring metal platinum (II) complex has one of the following structures:

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024] Furthermore, the application of the spirofluorene-biphenyl-acridine-based tetradentate fused-ring 6 / 5 / 6 metal platinum (II) complex phosphorescent luminescent material in a light-emitting device.

[0025] Furthermore, the application, characterized in that the light-emitting device is a light-emitting diode or a light-emitting electrochemical cell.

[0026] Further, for the application described above, the light-emitting device comprises a first electrode, a second electrode and at least one organic layer disposed between the first electrode and the second electrode, and at least one of the organic layers comprises the spirofluorene-biphenyl-acridine-based tetradentate fused-ring 6 / 5 / 6 platinum(II) complex phosphorescent material as described above.

[0027] Further, a light-emitting display device, characterized in that it comprises an organic light-emitting device, and the organic light-emitting device comprises a light-emitting layer made of the spirofluorene-biphenyl-acridine-based tetradentate fused-ring 6 / 5 / 6 platinum(II) complex phosphorescent material as described above.

[0028] Still further, a display device, characterized in that it comprises an organic light-emitting device, wherein the organic light-emitting device comprises a first electrode, a second electrode and at least one organic layer disposed between the first electrode and the second electrode, and at least one of the organic layers comprises the spirofluorene-biphenyl-acridine-based tetradentate fused-ring 6 / 5 / 6 platinum(II) complex phosphorescent material as described above.

[0029] The spirofluorene-biphenyl-acridine-based tetradentate 6 / 5 / 6 platinum(II) complex provided by the embodiments of the present invention has a rigid structure based on a biphenyl ligand, and large substituents such as spirofluorene rings and their derivatives effectively regulate the intermolecular forces.

[0030] In addition, the embodiments of the present invention further provide an optical device, which comprises one or more of the spirofluorene-biphenyl-acridine-based tetradentate fused-ring 6 / 5 / 6 platinum(II) complex phosphorescent materials.

[0031] Optionally, the device comprises a full-color display.

[0032] Optionally, the device is a photovoltaic device.

[0033] Optionally, the device is a light-emitting display device.

[0034] Optionally, the device comprises an organic light-emitting diode.

[0035] Optionally, the device comprises a phosphorescent organic light-emitting diode.

[0036] Compared with the prior art, the beneficial effects of the present invention are as follows: The phosphorescent complex provided by the present invention can increase the steric hindrance of the planar platinum(II) complex molecule through the spirofluorene group in the molecular structure, reduce the π-π stacking between molecules, thereby weakening the interaction between phosphorescent molecules and facilitating the sublimation and purification of material molecules; at the same time, it can weaken the triplet-triplet quenching between excited state molecules, which is beneficial to the improvement of the quantum efficiency of the material. The phosphorescent material of the present invention is a kind of phosphorescent material with high quantum efficiency and novel structure, and has great application prospects in the field of OLED materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to these drawings, where:

[0038] Figure 1 FIG. is the emission spectra of Pt(bp-1) in dichloromethane solution at room temperature and in 2-methyltetrahydrofuran solution at 77K in the specific embodiment;

[0039] Figure 2 FIG. is the emission spectra of Pt(bp-1-m) in dichloromethane solution at room temperature and in 2-methyltetrahydrofuran solution at 77K in the specific embodiment;

[0040] Figure 3 FIG. is the emission spectra of Pt(bp-1-m-t) in dichloromethane solution at room temperature and in 2-methyltetrahydrofuran solution at 77K in the specific embodiment;

[0041] Figure 4 FIG. is a combined diagram of the emission spectra of Pt(bp-1), Pt(bp-1-m) and Pt(bp-1-m-t) in dichloromethane solution at room temperature in the specific embodiment;

[0042] Figure 5 FIG. is a combined diagram of the emission spectra of Pt(bp-1), Pt(bp-1-m) and Pt(bp-1-m-t) in 2-methyltetrahydrofuran solution at 77K in the specific embodiment;

[0043] Table 1 shows the photophysical property data of Pt(bp-1), Pt(bp-1-m) and Pt(bp-1-m-t) in dichloromethane solution at room temperature and in 2-methyltetrahydrofuran solution at 77K respectively;

[0044] Table 2 shows the DFT calculations using Spartan software and the B3LYP / 6-31G / LANL2DZ basis set based on the optimized S0. The optimized spatial configurations, HOMO and LUMO energy levels, and dihedral angles of these complexes obtained from the DFT calculations are listed in the table.

[0045] The advantages are achieved and obtained by the elements and combinations specifically recited in the claims. It should be noted that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive. Detailed Description of the Invention

[0046] The present disclosure can be more readily understood by reference to the following detailed description and the examples contained therein. Before the compounds, devices, and / or methods of the invention are disclosed and described, it is to be understood that, unless otherwise indicated, the methods are not limited to particular synthetic methods or to particular reagents, as such may vary. It is also to be understood that the terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the exemplary methods and materials are now described.

[0047] As used in the specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a component" includes mixtures of two or more components.

[0048] As used herein, the term "optional" or "optionally" means that the subsequent described event or circumstance may or may not occur, and that the description includes instances where the event or circumstance occurs and instances where it does not.

[0049] Components that can be used to prepare the compositions of the present invention, as well as the compositions themselves to be used in the methods disclosed in the present invention, are disclosed. These and other materials are disclosed in the present invention, and it should be understood that combinations, subsets, interactions, groups, etc. of these substances are disclosed. Although specific references to each different individual and total combination and arrangement of these compounds are not specifically disclosed, each is specifically contemplated and described. For example, if a specific compound is disclosed and discussed, and many modifications that can be made to many molecules containing that compound are discussed, then each combination and arrangement of that compound and the possible modifications are specifically considered, unless the contrary possible modifications are specifically indicated. Thus, if a class of molecules A, B, and C and a class of molecules D, E, and F are disclosed, and an example of the combined molecule A-D is disclosed, then each individual and total meaning combination, A-E, A-F, B-D, B-E, B-F, C-D, C-E, and C-F is considered to be disclosed even if each is not individually recited. Similarly, any subset or combination of these is also disclosed. For example, sub-groups of A-E, B-F, and C-E are also disclosed. This concept applies to all aspects of the present invention, including but not limited to the steps in the methods of preparing and using the compositions. Thus, if there are various additional steps that can be carried out, it should be understood that each of these additional steps can be carried out in a specific embodiment of the method or in a combination of embodiments.

[0050] The linking atoms used in the present invention can link two groups, for example, linking N and C. The linking atom can optionally (if the valence bond permits) attach other chemical groups. For example, an oxygen atom will not have any other chemical groups attached because once two atoms (e.g., N or C) are bonded, the valence bond is already satisfied. In contrast, when carbon is the linking atom, two additional chemical groups can be attached to the carbon atom. Suitable chemical groups include but are not limited to hydrogen, hydroxyl, alkyl, alkoxy, =O, halogen, nitro, amine, amide, mercapto, aryl, heteroaryl, cycloalkyl, and heterocyclic group.

[0051] The term "cyclic structure" or similar terms used in the present invention refers to any cyclic chemical structure, including but not limited to aryl, heteroaryl, cycloalkyl, cycloalkenyl, heterocyclic group, carbene, and N-heterocyclic carbene.

[0052] As used herein, the term "substituted" or similar terms encompass all permissible substituents of an organic compound. Broadly, permissible substituents include cyclic and acyclic, branched and unbranched, carbocyclic and heterocyclic, aromatic and non-aromatic substituents of the organic compound. For example, exemplary substituents include those described below. For a suitable organic compound, the permissible substituents may be one or more and the same or different. For the purposes of the present invention, a heteroatom (e.g., nitrogen) can have a hydrogen substituent and / or any permissible substituent of the organic compounds described herein that satisfies the valence of the heteroatom. The present invention is not intended to be limited in any way by the permissible substituents of the organic compounds. Also, the terms "substituted" or "substituted with" include the implicit proviso that such substitution is in accordance with the permissible valences of the substituted atoms and the substituent, and that the substitution results in a stable compound (e.g., a compound that does not spontaneously undergo transformation (e.g., by rearrangement, cyclization, elimination, etc.)). In certain aspects, unless explicitly stated to the contrary, an individual substituent can further optionally be substituted (i.e., further substituted or unsubstituted).

[0053] In defining various terms, "R 1 ", "R 2 ", "R 3 ", and "R 4 " are used herein as general symbols to represent various specific substituents. These symbols can be any substituent, not limited to those disclosed in the present invention, and when they are defined as certain substituents in one instance, they can also be defined as some other substituents in another instance.

[0054] As used herein, the term "alkyl" refers to a branched or unbranched saturated hydrocarbon group having 1 to 30 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, tetradecyl, hexadecyl, eicosyl, tetracosyl, etc. The alkyl can be cyclic or acyclic. The alkyl can be branched or unbranched. The alkyl can also be substituted or unsubstituted. For example, the alkyl can be substituted with one or more groups including, but not limited to, optionally substituted alkyl, cycloalkyl, alkoxy, amino, ether, halogen, hydroxy, nitro, silyl, thio-oxo group, and mercapto as described herein. The "lower alkyl" group is an alkyl group containing 1 to 6 (e.g., 1 to 4) carbon atoms.

[0055] Throughout the specification, "alkyl" generally refers to both unsubstituted alkyl and substituted alkyl at the same time; however, substituted alkyl is also specifically referred to in the present invention by determining the specific substituents on the alkyl. For example, the term "halogenated alkyl" or "haloalkyl" specifically refers to an alkyl substituted with one or more halogens (e.g., fluorine, chlorine, bromine, or iodine). The term "alkoxyalkyl" specifically refers to an alkyl substituted with one or more alkoxy groups, as described below. The term "alkylamino" specifically refers to an alkyl substituted with one or more amino groups, as described below, etc. When "alkyl" is used in one case and a specific term such as "alkyl alcohol" is used in another case, it does not mean that the term "alkyl" does not simultaneously refer to specific terms such as "alkyl alcohol", etc.

[0056] This practice is also used for other groups described in the present invention. That is, when terms such as "cycloalkyl" simultaneously refer to unsubstituted and substituted cycloalkyl moieties, the substituted moiety can be specifically determined in the present invention; for example, a specifically substituted cycloalkyl can be referred to as, for example, "alkylcycloalkyl". Similarly, a substituted alkoxy can be specifically referred to as, for example, "haloalkoxy", and a specific substituted alkenyl can be, for example, "enol", etc. Likewise, the use of a general term such as "cycloalkyl" and a specific term such as "alkylcycloalkyl" does not mean that the general term does not simultaneously include the specific term.

[0057] The term "cycloalkyl" used in the present invention is a non-aromatic carbon-based ring consisting of 3 to 30 carbon atoms with at least three carbon atoms. Examples of cycloalkyl include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclononyl, etc. The term "heterocycloalkyl" is a type of cycloalkyl as defined above and is included in the meaning of the term "cycloalkyl", where at least one ring carbon atom is replaced by a heteroatom such as, but not limited to, nitrogen, oxygen, sulfur, or phosphorus. The cycloalkyl and heterocycloalkyl can be substituted or unsubstituted. The cycloalkyl and heterocycloalkyl can be substituted with one or more groups, including but not limited to alkyl, cycloalkyl, alkoxy, amino, ether, halogen, hydroxy, nitro, silyl, thio-oxo group, and mercapto group as described in the present invention.

[0058] The term "polyolefin group" used in the present invention refers to a group containing two or more CH2 groups connected to each other. The "polyolefin group" can be represented as —(CH2) a —, where "a" is an integer between 2 and 500.

[0059] The terms "alkoxy" and "alkoxy group" used in the present invention refer to an alkyl or cycloalkyl of 1 to 30 carbon atoms bonded through an ether bond; that is, "alkoxy" can be defined as —OR 1 where R 1 is an alkyl or cycloalkyl as defined above. "Alkoxy" also includes the alkoxy polymers just described; that is, alkoxy can be a polyether, such as —OR 1-OR 2 or - OR 1 -(OR 2 ) a -OR 3 , where "a" is an integer from 1 to 500, and R 1 , R 2 and R 3 are each independently an alkyl group, a cycloalkyl group or a combination thereof.

[0060] The term "alkenyl" used in the present invention is a hydrocarbon group having 2 to 30 carbon atoms, the structural formula of which contains at least one carbon-carbon double bond. Asymmetric structures such as (R 1 R 2 )C=C(R 3 R 4 ) include E and Z isomers. This can be presumed in the structural formula of the present invention where there is an asymmetric olefin, or it can be clearly indicated by the bond symbol C=C. The alkenyl group can be substituted with one or more groups including, but not limited to, the alkyl group, cycloalkyl group, alkoxy group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group, heteroaryl group, aldehyde group, amino group, carboxylic acid group, ester group, ether group, halogen group, hydroxyl group, ketone group, azide group, nitro group, silyl group, sulfur-oxo group or mercapto group described in the present invention.

[0061] The term "cycloalkenyl" used in the present invention is a non-aromatic carbon-based ring having 3 to 30 carbon atoms, which is composed of at least 3 carbon atoms and contains at least one carbon-carbon double bond, i.e., C=C. Examples of cycloalkenyl groups include, but are not limited to, cyclopropenyl group, cyclobutenyl group, cyclopentenyl group, cyclopentadienyl group, cyclohexenyl group, cyclohexadienyl group, cycloheptenyl group, etc. The term "heterocycloalkenyl" is a type of cycloalkenyl group defined as above and is included in the meaning of the term "cycloalkenyl", wherein at least one carbon atom of the ring is replaced by a heteroatom such as, but not limited to, nitrogen, oxygen, sulfur or phosphorus. The cycloalkenyl group and heterocycloalkenyl group can be substituted or unsubstituted. The cycloalkenyl group and heterocycloalkenyl group can be substituted with one or more groups including, but not limited to, the alkyl group, cycloalkyl group, alkoxy group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group, heteroaryl group, aldehyde group, amino group, carboxylic acid group, ester group, ether group, halogen group, hydroxyl group, ketone group, azide group, nitro group, silyl group, sulfur-oxo group or mercapto group described in the present invention.

[0062] The term "alkynyl" used in the present invention is a hydrocarbon group having 2 to 30 carbon atoms, the structural formula of which contains at least one carbon-carbon triple bond. The alkynyl group can be unsubstituted or substituted with one or more groups including, but not limited to, the alkyl group, cycloalkyl group, alkoxy group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group, heteroaryl group, aldehyde group, amino group, carboxylic acid group, ester group, ether group, halogen group, hydroxyl group, ketone group, azide group, nitro group, silyl group, sulfur-oxo group or mercapto group described in the present invention.

[0063] As used herein, the term "cycloalkynyl" refers to a non-aromatic carbon-based ring containing at least 7 carbon atoms and having at least one carbon-carbon triple bond. Examples of cycloalkynyl include, but are not limited to, cycloheptynyl, cyclooctynyl, cyclononynyl, and the like. The term "heterocycloalkynyl" is a type of cycloalkenyl as defined above and is included within the meaning of the term "cycloalkynyl", wherein at least one of the carbon atoms of the ring is replaced by a heteroatom, such as, but not limited to, nitrogen, oxygen, sulfur, or phosphorus. Cycloalkynyl and heterocycloalkynyl may be substituted or unsubstituted. Cycloalkynyl and heterocycloalkynyl may be substituted with one or more groups, including, but not limited to, alkyl, cycloalkyl, alkoxy, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl, heteroaryl, aldehyde, amino, carboxylic acid, ester, ether, halogen, hydroxy, ketone, azide, nitro, silyl, thioxo group, or mercapto group as described herein.

[0064] As used herein, the term "aryl" refers to a group containing any carbon-based aromatic group of 60 carbon atoms or less, including, but not limited to, benzene, naphthalene, phenyl, biphenyl, phenoxyphenyl, and the like. The term "aryl" also includes "heteroaryl", which is defined as a group containing an aromatic group having at least one heteroatom within the ring. Examples of heteroatoms include, but are not limited to, nitrogen, oxygen, sulfur, or phosphorus. Similarly, the term "non-heteroaryl" (which is also included within the term "aryl") defines a group containing an aromatic group that does not contain a heteroatom. Aryl may be substituted or unsubstituted. Aryl may be substituted with one or more groups, including, but not limited to, alkyl, cycloalkyl, alkoxy, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl, heteroaryl, aldehyde, amino, carboxylic acid, ester, ether, halogen, hydroxy, ketone, azide, nitro, silyl, thioxo group, or mercapto group as described herein. The term "biaryl" is a specific type of aryl and is included within the definition of "aryl". Biaryl refers to two aryl groups joined together by a fused ring structure, as in naphthalene, or two aryl groups joined by one or more carbon-carbon bonds, as in biphenyl.

[0065] As used herein, the term "aldehyde" is represented by the formula —C(O)H. Throughout the specification, "C(O)" is a shorthand form for a carbonyl group (i.e., C═O).

[0066] As used herein, the term "amine" or "amino" is represented by the formula —NR 1 R 2 wherein R 1 and R 2 may be independently selected from hydrogen, alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl, or heteroaryl.

[0067] The term "alkylamino" used in the present invention is represented by the formula —NH(-alkyl), where alkyl is as described in the present invention. Representative examples include, but are not limited to, methylamino, ethylamino, propylamino, isopropylamino, butylamino, isobutylamino, sec-butylamino, tert-butylamino, pentylamino, isopentylamino, tert-pentylamino, hexylamino, etc.

[0068] The term "dialkylamino" used in the present invention is represented by the formula —N(-alkyl)2, where alkyl is as described in the present invention. Representative examples include, but are not limited to, dimethylamino, diethylamino, dipropylamino, diisopropylamino, dibutylamino, diisobutylamino, di-sec-butylamino, di-tert-butylamino, dipentylamino, diisopentylamino, di-tert-pentylamino, dihexylamino, N-ethyl-N-methylamino, N-methyl-N-propylamino, N-ethyl-N-propylamino, etc.

[0069] The term "carboxylic acid" used in the present invention is represented by the formula —C(O)OH.

[0070] The term "ester" used in the present invention is represented by the formula —OC(O)R 1 or —C(O)OR 1 where R 1 can be alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl or heteroaryl as described in the present invention. The term "polyester" used in the present invention is represented by the formula —(R 1 O(O)C-R 2 -C(O)O) a — or —(R 1 O(O)C-R 2 -OC(O)) a — where R 1 and R 2 can independently be alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl or heteroaryl as described in the present invention and "a" is an integer from 1 to 500. The term "polyester" is used to describe a group produced by the reaction between a compound having at least two carboxyl groups and a compound having at least two hydroxyl groups.

[0071] The term "ether" used in the present invention is represented by the formula R 1 OR 2 where R 1 and R 2 can independently be alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl or heteroaryl as described in the present invention. The term "polyether" used in the present invention is represented by the formula —(R 1 O-R 2 O) a — where R 1 and R 2may be independently an alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl or heteroaryl as described in the present invention, and "a" is an integer from 1 to 500. Examples of polyether groups include polyethylene oxide, polypropylene oxide and polybutylene oxide.

[0072] As used herein, the term "halogen" refers to fluorine, chlorine, bromine and iodine.

[0073] As used herein, the term "heterocyclic group" refers to monocyclic and polycyclic non-aromatic ring systems having from 3 to 30 carbon atoms, and the term "heteroaryl" as used herein refers to monocyclic and polycyclic aromatic ring systems having no more than 60 carbon atoms: wherein at least one of the ring members is not carbon. The term includes azetidinyl, dioxolanyl, furanyl, imidazolyl, isothiazolyl, isoxazolyl, morpholinyl, oxazolyl (including oxazolyl such as 1,2,3-oxadiazolyl, 1,2,5-oxadiazolyl and 1,3,4-oxadiazolyl), piperazinyl, piperidinyl, pyrazinyl, pyrazolyl, pyridazinyl, pyridyl, pyrimidinyl, pyrrolyl, pyrrolidinyl, tetrahydrofuranyl, tetrahydropyranyl, tetrazinyl including 1,2,4,5-tetrazinyl, tetrazolyl including 1,2,3,4-tetrazolyl and 1,2,4,5-tetrazolyl, thiadiazolyl including 1,2,3-thiadiazolyl, 1,2,5-thiadiazolyl and 1,3,4-thiadiazolyl, thiazolyl, thienyl, triazinyl including 1,3,5-triazinyl and 1,2,4-triazinyl, triazolyl including 1,2,3-triazolyl and 1,3,4-triazolyl, etc.

[0074] As used herein, the term "hydroxy" is represented by the formula —OH.

[0075] As used herein, the term "ketone" is represented by the formula R 1 C(O)R 2 wherein R 1 and R 2 may be independently an alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl or heteroaryl as described in the present invention.

[0076] As used herein, the term "azido" is represented by the formula —N3.

[0077] As used herein, the term "nitro" is represented by the formula —NO2.

[0078] As used herein, the term "nitrile" is represented by the formula —CN.

[0079] As used herein, the term "silyl" is represented by the formula —SiR 1 R 2 R 3 wherein R 1 , R 2 and R 3It can be independently hydrogen or an alkyl group, cycloalkyl group, alkoxy group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group as described in the present invention.

[0080] The term "sulfur-oxo group" used in the present invention is represented by the formula —S(O)R 1 , —S(O)2R 1 , —OS(O)2R 1 or —OS(O)2OR 1 , where R 1 can be hydrogen or an alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group as described in the present invention. Throughout the specification, "S(O)" is a shorthand form of S═O. The term "sulfonyl group" used in the present invention refers to a sulfur-oxo group represented by the formula —S(O)2R 1 , where R 1 can be an alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group. The term "sulfone" used in the present invention is represented by the formula R 1 S(O)2R 2 , where R 1 and R 2 can be independently an alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group as described in the present invention. The term "sulfoxide" used in the present invention is represented by the formula R 1 S(O)R 2 , where R 1 and R 2 can be independently an alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group as described in the present invention.

[0081] The term "mercapto group" used in the present invention is represented by the formula —SH.

[0082] The "R 1 ", "R 2 ", "R 3 ", "R n " (where n is an integer) used in the present invention can independently have one or more of the groups listed above. For example, if R 1 is a straight-chain alkyl group, then one hydrogen atom of the alkyl group can be optionally substituted with a hydroxyl group, alkoxy group, alkyl group, halogen, etc. Depending on the selected group, the first group can be incorporated within the second group, or the first group can be attached (i.e., linked) to the second group. For example, for the phrase "alkyl group containing an amino group", the amino group can be incorporated within the main chain of the alkyl group. Alternatively, the amino group can be linked to the main chain of the alkyl group. The nature of the selected group will determine whether the first group is embedded or linked to the second group.

[0083] The compounds of the present invention may contain "optionally substituted" moieties. Generally, the term "substituted" (whether or not the term "optionally" precedes it) means that one or more hydrogens of the designated moiety are replaced by suitable substituents. Unless otherwise specified, an "optionally substituted" group may have suitable substituents at each substitutable position of the group, and when more than one position in any given structure can be substituted by more than one substituent selected from the designated group, the substituents may be the same or different at each position. The combinations of substituents contemplated by the present invention are preferably combinations that form stable or chemically viable compounds. It is also contemplated that in some aspects, unless explicitly stated to the contrary, each individual substituent may be further optionally substituted (i.e., further substituted or unsubstituted).

[0084] The structure of the compound can be represented by the following formula:

[0085]

[0086] which is understood to be equivalent to the following formula:

[0087]

[0088] wherein n is generally an integer. That is, R n is understood to represent five individual substituents R n(a) 、R n(b) 、R n(c) 、R n(d) 、R n (e) 。“Individual substituent” means that each R substituent can be defined independently. For example, if in one case R n(a) is a halogen, then in this case R n(b) is not necessarily a halogen.

[0089] R 1 、R 2 、R 3 、R 4 、R 5 、R 6 etc. are mentioned several times in the chemical structures and units disclosed and described in the present invention. Any description of R 1 、R 2 、R 3 、R 4 、R 5 、R 6 etc. in the specification applies separately to any structure or unit referring to R 1 、R 2 、R 3 、R 4 、R 5 、R 6 etc., unless otherwise specified.

[0090] As used in the present invention, the term "fused ring" means that two adjacent substituents can be fused into a six-membered aromatic ring, heteroaromatic ring, such as benzene ring, pyridine ring, pyrazine ring, pyridazine ring, m-diazine ring, etc., and saturated six-membered or seven-membered carbocyclic or carbheterocyclic rings, etc.

[0091] Due to various reasons, the use of organic materials in optoelectronic devices has become increasingly urgent. Many materials used to fabricate such devices are relatively inexpensive, so organic optoelectronic devices have the potential for cost advantages over inorganic devices. In addition, the inherent properties of organic materials, such as their flexibility, can make them very suitable for special applications such as fabrication on flexible substrates. Examples of organic optoelectronic devices include organic light-emitting devices (OLEDs), organic phototransistors, organic photovoltaic cells, and organic photodetectors. For OLEDs, organic materials may have performance advantages over conventional materials. For example, the wavelength of light emitted by the organic light-emitting layer can usually be easily tuned with appropriate dopants.

[0092] Excitons decay from the singlet excited state to the ground state to produce prompt luminescence, which is fluorescence. If excitons decay from the triplet excited state to the ground state to produce luminescence, this is phosphorescence. Due to the strong spin-orbit coupling of heavy metal atoms between the singlet and triplet excited states, effectively enhancing intersystem crossing (ISC), phosphorescent metal complexes (such as platinum complexes) have shown their potential to utilize both singlet and triplet excitons simultaneously, achieving 100% internal quantum efficiency. Therefore, phosphorescent metal complexes are good candidates for dopants in the emissive layer of organic light-emitting devices (OLEDs) and have received great attention in academic and industrial fields. In the past decade, many achievements have been made, leading to the profitable commercialization of this technology. For example, OLEDs have been used in advanced displays for smartphones, TVs, and digital cameras.

[0093] The metal complexes of the present invention can be customized or tuned for specific applications that are desired to have specific emission or absorption characteristics. The optical properties of the metal complexes in the present disclosure can be adjusted by changing the structure of the ligands around the metal center or by changing the structure of the fluorescent emitters on the ligands. For example, in the emission and absorption spectra, metal complexes of ligands with electron-donating substituents or electron-withdrawing substituents usually can exhibit different optical properties. The color of the metal complexes can be adjusted by modifying the conjugated groups on the fluorescent emitters and ligands.

[0094] Compounds or complex complexes containing platinum are disclosed herein. The terms compound or complex are used interchangeably in the present invention. Additionally, the compounds disclosed herein have a neutral charge.

[0095] The compounds disclosed herein can exhibit desired properties and have emission and / or absorption spectra that can be tuned by selecting appropriate ligands. In another aspect, the present invention can exclude any one or more of the compounds, structures or portions thereof specifically recited herein.

[0096] The compounds disclosed herein are suitable for a variety of optical and electro-optical devices, including but not limited to light absorption devices such as solar and photosensitive devices, organic light emitting diodes (OLEDs), light emitting devices or devices capable of compatible light absorption and emission, and as markers for biological applications.

[0097] As described above, the disclosed compounds are platinum complexes. Also, the compounds disclosed herein can be used as host materials for OLED applications, such as full-color displays.

[0098] The compounds disclosed herein can be used in various applications. As a luminescent material, the compound can be used in organic light emitting diodes (OLEDs), light emitting devices and displays, and other light emitting devices.

[0099] 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.

[0100] The compounds disclosed herein can be delayed fluorescence and / or phosphorescence emitters. In one aspect, the compounds disclosed herein can be delayed fluorescence emitters. In one aspect, the compounds disclosed herein can be phosphorescence emitters. In another aspect, the compounds disclosed herein can be delayed fluorescence emitters and phosphorescence emitters.

[0101] The present disclosure can be more readily understood by reference to the following detailed description and the examples contained therein.

[0102] The following examples provide to those of ordinary skill in the art how to make and evaluate the compounds and their OLED devices described in the present invention. The examples are merely illustrative of the present disclosure and do not delimit the scope of the invention. Although efforts have been made to ensure the accuracy of the numerical values (e.g., amounts, temperatures, etc.), some errors and deviations should be considered. Unless otherwise stated, the temperatures are in °C or at ambient temperature, and the pressures are at or near atmospheric pressure.

[0103] The following examples provide methods for preparing new compounds, but the preparation of such compounds is not limited to this method. In this technical field, since the compounds protected in this patent are easy to modify and prepare, their preparation can adopt the methods listed below or other methods. The following examples are only for illustration and do not limit the scope of protection of this patent. The temperature, catalyst, concentration, reactants, and reaction process can all be changed to select different conditions for preparing the compounds for different reactants.

[0104] Performed on a Varian Liquid State NMR instrument 1 1H NMR (500 MHz) and 13 13C NMR (126 MHz) spectral tests. Unless otherwise specified, DMSO-d6 or CDCl3 containing 0.1% TMS was used as the solvent for NMR. Among them 1 For the 1H NMR spectrum, when CDCl3 was used as the solvent, if there was an internal standard tetramethylsilane in the solvent, the chemical shift was referenced to tetramethylsilane (δ = 0.00 ppm); otherwise, if CDCl3 was the solvent 1 the chemical shift of the 1H NMR spectrum was referenced to the residual solvent (δ = 7.26 ppm); when DMSO-d6 was used as the solvent, TMS (δ = 0.00 ppm) or the residual DMSO peak (δ = 2.50 ppm) or the residual water peak (δ = 3.33 ppm) was used as the internal standard. 13 In the 13C NMR spectrum, CDCl3 (δ = 77.00 ppm) or DMSO-d6 (δ = 39.52 ppm) was used as the internal standard. 1 In the 1H NMR spectrum data: s = singlet, single peak; d = doublet, double peak; t = triplet, triple peak; q = quartet, quadruple peak; p = quintet, quintuple peak; m = multiplet, multiple peak; br = broad, broad peak.

[0105] Synthesis route

[0106] The general synthesis procedure is as follows:

[0107]

[0108] Example 1: The luminescent material Pt(bp-1) can be synthesized according to the following route:

[0109]

[0110] (1) Synthesis of Intermediate C-OH: Add o-bromobiphenyl (2.56 g, 11.0 mmol, 1.7 eq) to a dry three-necked flask equipped with a magnetic stir bar, and add tetrahydrofuran (70 mL) under nitrogen protection. Then place the reaction in an ethanol bath and cool it to -78 °C with liquid nitrogen. Slowly add n-butyllithium (7.00 mL, 11.00 mmol, 1.7 eq, 1.60 mol / L n-hexane solution). After reacting for 3 hours, add 3-bromophenyl-2-pyridinecarboxaldehyde (1.80 mg, 6.90 mmol, 1.00 eq), and stir at room temperature for 24 hours. Quench the reaction mixture with saturated ammonium chloride solution, and extract it three times with ethyl acetate. Combine the organic phases, dry over anhydrous sodium sulfate, filter, and remove the solvent under reduced pressure. Purify the obtained crude product by silica gel column chromatography, eluent: petroleum ether / ethyl acetate = 20:1 - 10:1, to obtain 2.60 g of the product C-OH, a colorless transparent oily liquid, with a yield of 90%. 1 H NMR (500 MHz, DMSO): δ 6.71 (s, 1H), 6.88 - 6.86 (m, 3H), 6.95 (t, J = 7.0 Hz, 2H), 7.03 - 6.98 (m, 2H), 7.06 (ddd, J = 1.0, 5.0, 6.0 Hz, 1H), 7.14 (t, J = 8.0 Hz, 1H), 7.25 (td, J = 1.5, 7.5 Hz, 1H), 7.33 - 7.29 (m, 3H), 7.44 - 7.42 (m, 1H), 7.47 (td, J = 1.5, 7.5 Hz, 1H), 7.59 (t, J = 2.0 Hz, 1H), 8.35 (dq, J = 0.5, 4.5 Hz, 1H).

[0111] (2) Synthesis of Intermediate C-Br: Add C-OH (1.00 g, 2.40 mmol, 1.00 eq), acetic acid (25 mL) to a dry three-necked flask equipped with a magnetic stir bar, then add concentrated sulfuric acid (1 mL) and acetic anhydride (1 mL). Place the three-necked flask in an oil bath with magnetic stirring, and stir and react at 130 °C for 12 hours. Monitor the reaction by thin-layer chromatography until the raw materials are completely reacted. After the reaction is cooled to room temperature, remove the solvent under reduced pressure distillation, and then adjust the pH to weakly alkaline with saturated sodium carbonate solution. Then extract it three times with ethyl acetate, extract the aqueous layer twice with ethyl acetate, combine the organic phases, dry over anhydrous sodium sulfate, filter, and remove the solvent from the filtrate under reduced pressure distillation. Purify the obtained crude product by silica gel column chromatography, eluent: petroleum ether / ethyl acetate = 10:1 - 5:1, to obtain 920 mg of a white solid, with a yield of 96%. 11H NMR (500 MHz, DMSO-d6): δ 7.04 - 6.98 (m, 3H), 7.20 (t, J = 7.5 Hz, 1H), 7.28 (ddd, J = 6.0, 5.0, 1.0 Hz, 1H), 7.35 (td, J = 7.5, 1.0 Hz, 2H), 7.40 (ddd, J = 3.0, 2.0, 1.0 Hz, 1H), 7.44 (td, J = 7.5, 1.0 Hz, 2H), 7.57 (d, J = 7.5 Hz, 2H), 7.66 (td, J = 7.5, 2.0 Hz, 1H), 7.95 (d, J = 7.5 Hz, 2H), 8.59 (ddd, J = 2.5, 1.5, 0.5 Hz, 1H).

[0112] (3) Synthesis of intermediate A-Br: Add 3-bromoacridine (5.00 g, 17.35 mmol, 1.00 equiv), copper(I) iodide (331 mg, 1.74 mmol, 10 mol%), 1-methylimidazole (143 mg, 1.74 mmol, 10 mol%), and lithium tert-butoxide (2.08 mg, 26.03 mmol, 1.5 equiv) to a dry three-necked flask equipped with a magnetic stir bar. Then evacuate and refill with nitrogen three times. Under nitrogen protection, add 2-bromopyridine (3.28 g, 20.82 mmol, 1.2 equiv) and toluene (45 mL). The mixture is stirred and reacted in an oil bath at 115 °C for 36 h, and monitored by thin-layer chromatography until the raw materials are completely reacted. Cool to room temperature, and distill off the solvent under reduced pressure. The obtained crude product is separated and purified by silica gel column chromatography, eluent: petroleum ether / ethyl acetate = 15:1 - 10:1, to obtain product A-Br, 5.36 g of pale yellow oily liquid, yield 85%. 1 1H NMR (500 MHz, CDCl3) δ 1.65 (s, 6H), 6.73 (dd, J = 8.0, 1.5 Hz, 1H), 6.79 (d, J = 2.0 Hz, 1H), 7.00 (td, J = 7.5, 1.5 Hz, 1H), 7.03 - 7.07 (m, 1H), 7.08 (dd, J = 8.0, 2.0 Hz, 1H), 7.24 - 7.26 (m, 1H), 7.27 - 7.29 (m, 1H), 7.42 - 7.45 (m, 2H), 7.78 - 7.81 (m, 1H), 8.65 - 8.66 (m, 1H).

[0113] (4) Synthesis of Intermediate A-B: Add A-Br (1.00 g, 2.74 mmol, 1.00 equiv) into a dry sealed tube equipped with a magnetic stir bar, bis(pinacolato)diboron (1.39 g, 5.48 mmol, 2.00 equiv), [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium (100 mg, 0.14 mmol, 5 mol%), quickly add potassium acetate (806 mg, 8.22 mmol, 3.00 equiv), then evacuate and refill with nitrogen three times, and add dimethyl sulfoxide (20 mL) under nitrogen protection. Then place this sealed tube into an oil bath equipped with magnetic stirring, stir and react in an oil bath at 65 °C for 1 day, monitor by thin-layer chromatography, and the raw materials are not completely reacted; raise the temperature to 80 °C and continue to react for 1 day, monitor by thin-layer chromatography, and the raw materials are completely reacted. Cool the reaction mixture to room temperature, dilute with ethyl acetate, wash the organic phase with water twice, and extract the aqueous layer with ethyl acetate twice. Combine the organic phases, dry over anhydrous sodium sulfate, filter, and then distill off the solvent under reduced pressure for the filtrate. The obtained crude product is separated by silica gel column chromatography, eluent: petroleum ether / ethyl acetate = 30:1 - 15:1, to obtain 740 mg of white solid, yield 66%. 1 H NMR (500 MHz, DMSO-d6): δ (ppm) 1.21 (s, 12H), 1.58 (s, 6H), 6.49 (dd, J = 8.0, 1.5 Hz, 1H), 6.84 (d, J = 1.0 Hz, 1H), 6.99 (td, J = 7.5, 1.0 Hz, 1H), 7.04 (td, J = 7.0, 1.5 Hz, 1H), 7.32 (dd, J = 7.5, 1.0 Hz, 1H), 7.41 (dt, J = 8.0, 1.0 Hz, 1H), 7.47 - 7.50 (m, 2H), 7.51 (d, J = 7.5 Hz, 1H), 8.06 (td, J = 7.5, 2.0 Hz, 1H), 8.72 (ddd, J = 5.0, 2.0, 0.5 Hz, 1H).

[0114] (5) Synthesis of ligand L(bp-1): Add A-B (500 mg, 1.21 mmol, 1.00 equiv), C-Br (483 mg, 1.21 mmol, 1.00 equiv), tetrakis(triphenylphosphine)palladium (71 mg, 0.061 mmol, 5 mol%), and potassium carbonate (335 mg, 2.42 mmol, 2.0 equiv) into a dry three-necked flask equipped with a magnetic stir bar. Then evacuate and refill with nitrogen three times, and add 1,4-dioxane (12 mL) and water (3 mL) under nitrogen protection. Next, place the three-necked flask in an oil bath with magnetic stirring and stir the reaction at 90 °C for 24 hours, monitoring by thin-layer chromatography until the raw materials are completely reacted. Cool the reaction to room temperature and remove the solvent by rotary evaporation under reduced pressure. The obtained crude product is separated by silica gel column chromatography, eluent: petroleum ether / ethyl acetate / dichloromethane = 20:1:3 - 10:1:3, to obtain L(bp-1), 672 mg of white foamy solid, with a yield of 92%. 1 H NMR (500 MHz, DMSO-d6): δ (ppm) 1.59 (s, 6H), 6.30 (d, J = 2.0 Hz, 1H), 6.32 (dd, J = 8.0, 1.5 Hz, 1H), 6.84 (t, J = 1.5 Hz, 1H), 6.88 (dt, J = 7.5, 1.0 Hz, 1H), 6.96 (td, J = 7.5, 1.0 Hz, 1H), 7.01 (td, J = 8.0, 2.0 Hz, 1H), 7.05 - 7.08 (m, 2H), 7.22 (t, J = 8.0 Hz, 1H), 7.27 - 7.32 (m, 4H), 7.38 (d, J = 7.5 Hz, 1H), 7.43 (t, J = 7.5 Hz, 2H), 7.47 - 7.52 (m, 4H), 7.59 - 7.61 (m, 1H), 7.65 (td, J = 8.0, 2.0 Hz, 1H), 7.94 (d, J = 8.0 Hz, 2H), 8.05 (td, J = 8.0, 2.0 Hz, 1H), 8.52 (dd, J = 4.5, 1.5 Hz, 1H), 8.68 (dd, J = 5.0, 1.5 Hz, 1H).

[0115] (6) Synthesis of Pt(bp-1): Add L(bp-1) (150 mg, 0.25 mmol, 1.00 equiv) and platinum(II) chloride (69 mg, 0.26 mmol, 1.05 equiv) to a dry three-necked flask equipped with a magnetic stir bar. Then evacuate and refill with nitrogen three times, and add benzonitrile (15 mL) under nitrogen protection. Place the three-necked flask in an oil bath with magnetic stirring and stir the reaction at 180 °C for 3 days. Monitor the reaction by TLC until the raw materials are completely reacted. After the reaction is cooled to room temperature, remove the solvent by rotary evaporation. The crude product is separated by silica gel column chromatography, eluent: petroleum ether / dichloromethane = 2:1 - 1:1, to obtain 141 mg of a yellow solid with a yield of 71%. HRMS(ESI): calcd for C 52 H 50 N3[M+H] + 797.2157, found 797.2174.

[0116] Example 2: The luminescent material Pt(bp-1-m) can be synthesized according to the following route:

[0117]

[0118] (1) Synthesis of intermediate A-m-B: Add A-m-Br (5.00 g, 13.20 mmol, 1.00 equiv), bis(pinacolato)diboron (5.02 g, 19.77 mmol, 1.50 equiv), [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium(II) (388 mg, 0.53 mmol, 4 mol%) to a dry sealed tube equipped with a magnetic stir bar. Quickly add potassium acetate (3.89 g, 39.60 mmol, 3.00 equiv), then evacuate and refill with nitrogen three times, and add dimethyl sulfoxide (80 mL) under nitrogen protection. Then place the sealed tube in an oil bath with magnetic stirring and stir the reaction at 75 °C for 48 hours. Monitor the reaction by TLC, and the raw materials are not completely reacted; raise the temperature to 80 °C and continue the reaction for 24 hours. Monitor the reaction by TLC until the raw materials are completely reacted. Cool the reaction to room temperature, dilute with ethyl acetate, wash the organic phase with water twice, and extract the aqueous layer with ethyl acetate twice. Combine the organic phases, dry over anhydrous sodium sulfate, filter, and remove the solvent from the filtrate by rotary evaporation. The crude product is separated by silica gel column chromatography, eluent: petroleum ether / ethyl acetate = 30:1 - 10:1, to obtain 4.32 g of a white solid with a yield of 77%. 11H NMR (400 MHz, CDCl3): δ (ppm) 1.27 (s, 12H), 1.64 (s, 6H), 2.38 (s, 3H), 6.81 (dd, J = 8.0, 1.2 Hz, 1H), 7.00 (td, J = 7.6, 1.6 Hz, 1H), 7.04 - 7.09 (m, 2H), 7.12 (s, 1H), 7.26 (s, 1H), 7.43 (dd, J = 7.6, 1.2 Hz, 1H), 7.46 - 7.49 (m, 2H), 8.53 (d, J = 5.2 Hz, 1H).

[0119] (2) Synthesis of ligand L(bp - 1 - m): Add A - m - B (469 mg, 1.10 mmol, 1.10 equiv), C - Br (400 mg, 1.00 mmol, 1.00 equiv), tetrakis(triphenylphosphine)palladium(0) (58 mg, 0.05 mmol, 5 mol%), and potassium carbonate (276 mg, 2.00 mmol, 2.0 equiv) to a dry three - necked flask equipped with a magnetic stir bar. Then evacuate and refill with nitrogen three times, and add 1,4 - dioxane (12 mL) and water (3 mL) under nitrogen protection. Then place the three - necked flask in an oil bath with magnetic stirring and stir at 90 °C for 48 h, monitoring by thin - layer chromatography until the raw materials are completely reacted. Cool the reaction to room temperature, remove the solvent by rotary evaporation under reduced pressure, dilute with ethyl acetate, wash the organic phase twice with water, and extract the aqueous layer twice with ethyl acetate. Combine the organic phases, dry over anhydrous sodium sulfate, filter, and remove the solvent from the filtrate by rotary evaporation under reduced pressure. The obtained crude product is separated by silica gel column chromatography, eluent: petroleum ether / ethyl acetate / dichloromethane = 20:1:1 - 15:1:1, to obtain L(bp - 1 - m), 525 mg of white solid, yield 77%. 1 1H NMR (500 MHz, DMSO - d6): δ (ppm) 1.60 (s, 6H), 2.40 (s, 3H), 6.21 (d, J = 2.0 Hz, 1H), 6.24 (dd, J = 10.0, 1.0 Hz, 1H), 6.83 (s, 1H), 6.86 (d, J = 10.0 Hz, 1H), 6.95 (td, J = 9.0, 1.0 Hz, 1H), 6.99 (td, J = 10.0, 2.0 Hz, 1H), 7.04 - 7.07 (m, 2H), 7.22 (t, J = 9.5 Hz, 1H), 7.26 - 7.32 (m, 5H), 7.41 - 7.53 (m, 7H), 7.65 (td, J = 9.5, 2.0 Hz, 1H), 7.95 (d, J = 9.0 Hz, 2H), 8.52 - 8.53 (m, 1H), 8.56 (d, J = 6.5 Hz, 1H). HRMS(ESI): calcd for C 45 1H 36N3[M+H] + 618.2909, found 618.2904。

[0120] (3) Synthesis of Pt(bp-1-m): Add L(bp-1-m) (300 mg, 0.49 mmol, 1.00 equivalent) and platinum dichloride (136 mg, 0.51 mmol, 1.05 equivalent) to a dry three-necked flask equipped with a magnetic stir bar, then evacuate and refill with nitrogen three times, and add benzonitrile (20 mL) under nitrogen protection. Place the three-necked flask in an oil bath with magnetic stirring and stir at 180 °C for 3 days, monitoring by thin-layer chromatography until the raw materials are completely reacted. After the reaction cools to room temperature, add tetrahydrofuran (10 mL) and potassium tert-butoxide (550 mg, 4.90 mmol, 10.0 equivalents) to the mixture under a nitrogen atmosphere, and stir in an oil bath at 76 °C for 12 hours. After the reaction cools to room temperature, remove the solvent by rotary evaporation under reduced pressure. The resulting crude product was separated by silica gel column chromatography, eluent: petroleum ether / dichloromethane = 2:1 - 1:1, to obtain 135 mg of a light brownish-yellow solid, with a yield of 34%. 1 H NMR (500 MHz, DMSO-d6): δ (ppm) 1.36 (s, 3H), 1.87 (s, 3H), 2.27 (s, 3H), 6.03 (dd, J = 8.0, 1.0 Hz, 1H), 6.50 (t, J = 8.0 Hz, 1H), 6.97 (d, J = 7.5 Hz, 1H), 7.06 (t, J = 8.5 Hz, 2H), 7.09 - 7.12 (m, 2H), 7.14 (dd, J = 6.0, 1.0 Hz, 1H), 7.19 (td, J = 7.5, 1.0 Hz, 1H), 7.23 - 7.28 (m, 2H), 7.33 - 7.35 (m, 2H), 7.50 - 7.55 (m, 2H), 7.58 - 7.62 (m, 2H), 7.65 (ddd, J = 7.5, 6.0, 2.5 Hz, 1H), 7.84 - 7.90 (m, 2H), 8.10 (d, J = 7.5 Hz, 1H), 8.43 (d, J = 6.0 Hz, 1H), 9.10 (dd, J = 5.5, 1.5 Hz, 1H), 9.33 (d, J = 7.5 Hz, 1H). HRMS (ESI): calcd for C 45 H 34 N3Pt[M+H] + 811.2400, found 811.2395。

[0121] Example 3: The luminescent material Pt(bp-1-m-t) can be synthesized according to the following route:

[0122]

[0123] (1) Synthesis of intermediate C-t-OH: Add 2-bromo-4,4'-di-tert-butylbiphenyl (1.26 g, 3.63 mmol, 1.0 equiv) to a dry three-necked flask equipped with a magnetic stir bar. Under nitrogen protection, add tetrahydrofuran (40 mL). Place the reaction apparatus in an ethanol bath and cool it to -78 °C with liquid nitrogen. Then slowly add n-butyllithium (2.30 mL, 3.63 mmol, 1.0 equiv, 1.60 mol / L n-hexane solution). After reacting for 3 hours, add 3-bromophenyl-2-pyridinecarboxaldehyde (1.00 mg, 3.80 mmol, 1.05 equiv). Stir at room temperature for 24 hours. Quench the reaction mixture with a saturated solution of ammonium chloride, and then extract it three times with ethyl acetate. Extract the aqueous layer twice with ethyl acetate. Combine the organic phases, dry over anhydrous sodium sulfate, filter, and then remove the solvent by rotary evaporation under reduced pressure. Purify the crude product by silica gel column chromatography with eluent: petroleum ether / ethyl acetate = 40:1 - 20:1 to obtain 1.50 g of the product C-t-OH, an oily colorless transparent liquid, with a yield of 78%. 1 1H NMR (500 MHz, CDCl3): δ 1.21 (s, 9H), 1.25 (s, 9H), 6.89 (d, J = 8.0 Hz, 2H), 7.06 - 7.00 (m, 4H), 7.13 - 7.07 (m, 4H), 7.28 (t, J = 6.5 Hz, 2H), 7.34 (dd, J = 8.0, 1.5 Hz, 1H), 7.50 (t, J = 7.5 Hz, 1H), 7.54 (s, 1H), 8.37 (d, J = 4.5 Hz, 1H).

[0124] (2) Synthesis of intermediate C-t-Br: Add C-t-Br (1.50 g, 2.84 mmol, 1.00 equiv), acetic acid (25 mL) to a dry three-necked flask equipped with a magnetic stir bar. Then add concentrated sulfuric acid (1.2 mL) and acetic anhydride (1 mL). Place the three-necked flask in an oil bath with magnetic stirring and stir at 130 °C for 12 hours. Monitor the reaction by thin-layer chromatography until the raw materials are completely reacted. After cooling the reaction to room temperature, remove the solvent by rotary evaporation under reduced pressure, and then adjust the pH to weakly basic with a saturated solution of sodium carbonate. Then extract it three times with ethyl acetate. Extract the aqueous layer twice with ethyl acetate. Combine the organic phases, dry over anhydrous sodium sulfate, filter, and then remove the solvent by rotary evaporation under reduced pressure. Purify the crude product by silica gel column chromatography with eluent: petroleum ether / ethyl acetate = 20:1 - 10:1 to obtain 1.5 g of an oily colorless transparent liquid, with a yield of 99%. 11H NMR (500 MHz, CDCl3): δ 1.30 (s, 18H), 6.99 (d, J = 6.0 Hz, 1H), 7.16 (s, 1H), 7.25 - 7.21 (m, 2H), 7.40 (dd, J = 8.0, 1.5 Hz, 2H), 7.51 (s, 1H), 7.60 (s, 1H), 7.65 (d, J = 8.0 Hz, 3H), 7.68 - 7.66 (m, 2H), 8.71 (s, 1H).

[0125] (3) Synthesis of ligand L(bp-1-m-t): Add A-m-B (307 mg, 0.72 mmol, 1.05 equiv), C-t-Br (350 mg, 0.69 mmol, 1.00 equiv), tetrakis(triphenylphosphine)palladium(0) (40 mg, 0.034 mmol, 5 mol%), and potassium carbonate (190 mg, 1.37 mmol, 2.0 equiv) into a dry three-necked flask equipped with a magnetic stir bar. Then evacuate and refill with nitrogen three times, and add the solvents 1,4-dioxane (12 mL) and water (3 mL) under nitrogen protection. Next, place the three-necked flask in an oil bath with magnetic stirring and stir at 90 °C for 48 h, monitoring by thin-layer chromatography until the raw materials are completely reacted. Cool the reaction to room temperature, remove the solvent by rotary evaporation under reduced pressure, and dilute with ethyl acetate. Wash the organic phase twice with water, and extract the aqueous layer twice with ethyl acetate. Combine the organic phases, dry over anhydrous sodium sulfate, filter, and remove the solvent from the filtrate by rotary evaporation under reduced pressure. The obtained crude product is separated by silica gel column chromatography, eluent: petroleum ether / ethyl acetate / dichloromethane = 20:1:2 - 15:1:2, to obtain L(bp-1-m-t), 400 mg of white solid, with a yield of 79%. 1 1H NMR (500 MHz, DMSO-d6): δ (ppm) 1.23 (s, 18H), 1.57 (s, 6H), 6.56 (d, J = 9.5 Hz, 1H), 6.62 (d, J = 1.5 Hz, 1H), 6.90 (dt, J = 8.5, 2.5 Hz, 1H), 6.70 - 7.12 (m, 5H), 7.21 - 7.29 (m, 3H), 7.32 (d, J = 10.0 Hz, 1H), 7.42 - 7.46 (m, 3H), 7.48 - 7.52 (m, 2H), 7.56 (d, J = 1.0 Hz, 2H), 7.66 (td, J = 9.5, 2.0 Hz, 1H), 7.78 (d, J = 10.0 Hz, 2H), 7.95 (td, J = 10.0, 2.5 Hz, 1H), 8.56 (t, J = 3.0 Hz, 2H).

[0126] (4) Synthesis of Pt(bp-1-m-t): Add L(bp-1-m-t) (300 mg, 0.42 mmol, 1.00 equivalent) and platinum dichloride (117 mg, 0.44 mmol, 1.05 equivalent) to a dry three-necked flask equipped with a magnetic stir bar. Then evacuate and refill with nitrogen three times, and add benzonitrile (20 mL) under nitrogen protection. Place the three-necked flask in an oil bath with magnetic stirring and stir at 180 °C for 3 days. Monitor the reaction by thin-layer chromatography until the raw materials are completely reacted. After the reaction is cooled to room temperature, remove the solvent by rotary evaporation under reduced pressure. The obtained crude product is separated by silica gel column chromatography, eluent: petroleum ether / dichloromethane = 1:2 - 1:1, to obtain 250 mg of a light yellow solid with a yield of 65%. 1 H NMR (400 MHz, DMSO-d6): δ (ppm) 1.03 (s, 9H), 1.37 (s, 12H), 1.87 (s, 3H), 2.25 (s, 3H), 6.04 (dd, J = 8.0, 0.4 Hz, 1H), 6.50 (t, J = 7.6 Hz, 1H), 6.96 (d, J = 7.6 Hz, 1H), 7.00 (d, J = 8.0 Hz, 1H), 7.10 (d, J = 7.6 Hz, 3H), 7.18 (td, J = 7.6, 1.6 Hz, 1H), 7.23 (td, J = 8.0, 1.2 Hz, 1H), 7.28 - 7.32 (m, 3H), 7.48 - 7.54 (m, 3H), 7.65 (dd, J = 8.0, 1.6 Hz, 1H), 7.69 (d, J = 8.0 Hz, 1H), 7.85 - 7.89 (m, 1H), 7.94 (d, J = 8.0 Hz, 1H), 8.46 (d, J = 6.0 Hz, 1H), 9.10 (dd, J = 5.6, 1.2 Hz, 1H), 9.38 (d, J = 1.6 Hz, 1H).

[0127] The above are only the embodiments of the present invention. It should be noted here that for those of ordinary skill in the art, without departing from the inventive concept of the present invention, improvements can still be made, but these all fall within the protection scope of the present invention.

[0128] Performance Evaluation

[0129] The following performs photophysical analysis on the complexes prepared in the above embodiments of the present invention.

[0130] Photophysical analysis: The test conditions for the emission spectrum of the complex luminescent material: Test at room temperature, and all samples are dilute solutions (10 -5 -10 -6M), and the full width at half maximum (FWHM) of the spectrum is the peak width at half of the peak height, that is, a straight line parallel to the peak base is drawn through the midpoint of the peak height, and the distance between the two intersection points of this straight line and both sides of the peak. In addition, the emission spectrum, quantum efficiency, excited state lifetime, etc. were all measured on a HORIBA Fluorolog-3 steady-state time-resolved fluorescence spectrometer. Meanwhile, the emission spectrum in dichloromethane at room temperature was measured on a HITACHI F-7000 spectrometer to study the effects of different spectrometers on the wavelength, FWHM, and shoulder peak height of the emission spectrum. The emission spectra of the luminescent materials described in Examples 1, 2, and 3 are as Figures 1 to 3 .

[0131] For the series of tetradentate fused-ring 6 / 5 / 6 platinum(II) metal complexes based on spirofluorene-biphenyl-acridine phosphorescent luminescent materials, the test conditions for the emission spectrum: the emission spectra in dichloromethane solution at room temperature and in 2-methyltetrahydrofuran solution at 77 K ( Figure 1 , Figure 2 and Figure 3 ), and other relevant photophysical data are recorded in Table (Table 1). For all Pt(II) complexes in this series, there are stable emission peaks ( Figure 1 , Figure 2 and Figure 3 , Table 1). At room temperature, the emission peak value in dichloromethane solution is at 505 - 506 nm, the excited state lifetime is 8.5 - 11.4 μs, and the quantum efficiency is 50% - 85%. In addition, the excited state lifetime τ of the bp Pt(II) complex in 2-methyltetrahydrofuran solution at 77 K is between 13.9 - 16.9 μs (Table 1).

[0132] Table 1. Photophysical properties of phosphorescent luminescent materials in different solutions at room temperature

[0133]

[0134] Figures 1 to 3 are the emission spectra of the three luminescent materials in Table 1 in dichloromethane solution at room temperature and in 2-methyltetrahydrofuran solution at 77 K respectively. From the above data, it can be seen that the maximum emission peaks of such tetradentate fused-ring 6 / 5 / 6 platinum(II) metal complexes based on spirofluorene-biphenyl-acridine phosphorescent luminescent materials are all at 505 - 506 nm in dichloromethane solution at room temperature. Figure 4 and Figure 5 are the combined diagrams of the emission spectra of the three luminescent materials synthesized in Examples 1, 2, and 3 at room temperature and in different solutions.

[0135] The phosphorescent material molecules in the examples all have good thermal stability and are easy to sublimate and purify due to the introduction of spirofluorene.

[0136] Table 2 shows the DFT calculations of a series of designed tetradentate platinum(II) complexes using Spartan software and the B3LYP / 6-31G / LANL2DZ basis set based on the optimized S0. The spatial configurations, dihedral angles, HOMO, and LUMO energy level data are listed in the table. The results show that the spatial configurations, HOMO, and LUMO energy levels of these complexes are not the same, indicating that the HOMO and LUMO energy levels and the excited state properties of the platinum(II) complexes can be effectively regulated through the rational design of the ligand structure. In addition, the spirofluorene group in them can form an orthogonal structure with the azaacridine in the molecule, effectively inhibiting molecular packing, reducing intermolecular interactions, and decreasing the rate of non-radiative transitions, thus facilitating the improvement of quantum efficiency.

[0137] Table 2. DFT Calculations Based on the B3LYP / 6-31G / LANL2DZ Basis Set of Optimized S0

[0138]

[0139]

[0140]

[0141]

[0142]

[0143] In an organic light-emitting device, carriers are injected from the positive and negative electrodes into the light-emitting material, generating an excited state of the light-emitting material and causing it to emit light. The phosphorescent light-emitting material based on the spirofluorene-biphenyl-azaacridine tetradentate fused-ring 6 / 5 / 6 metal platinum(II) complex of the present invention is applied to excellent organic light-emitting devices such as organic photoluminescent devices or organic electroluminescent devices. The organic photoluminescent device has a structure with at least a light-emitting layer formed on a substrate. In addition, the organic electroluminescent element has a structure with at least an anode, a cathode, and an organic layer between the anode and the cathode. The organic layer at least includes a light-emitting layer, and can be composed only of the light-emitting layer, or can have one or more organic layers in addition to the light-emitting layer. As such other organic layers, a hole transport layer, a hole injection layer, an electron blocking layer, a hole blocking layer, an electron injection layer, an electron transport layer, an exciton blocking layer, etc. can be cited. The hole transport layer can also be a hole injection and transport layer with a hole injection function, and the electron transport layer can also be an electron injection and transport layer with an electron injection function. The specific structure of the organic light-emitting element has a total of 7 layers from bottom to top, which are successively a substrate, an anode, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and a cathode, where the light-emitting layer is a mixed layer of a guest material doped into a host material.

[0144] Each layer of the organic light-emitting device of the present invention can be formed by methods such as vacuum evaporation, sputtering, ion plating, or wet film formation methods such as spin coating, printing, and printing. The solvents used are not particularly limited.

[0145] In a preferred embodiment of the present invention, the OLED device of the present invention contains a hole transport layer. The hole transport material can preferably be selected from known or unknown materials, and particularly preferably selected from the following structures, but this does not mean that the present invention is limited to the following structures:

[0146]

[0147] In a preferred embodiment of the present invention, the hole transport layer contained in the OLED device of the present invention contains one or more p-type dopants. The preferred p-type dopants of the present invention are the following structures, but this does not mean that the present invention is limited to the following structures:

[0148]

[0149]

[0150] In a preferred embodiment of the present invention, the electron transport layer can be selected from at least one of compounds ET-1 to ET-13, but this does not mean that the present invention is limited to the following structures:

[0151]

[0152] The electron transport layer can be formed by an organic material and one or more n-type dopants (such as LiQ).

[0153] The compound represented in Example 1 was used as a light-emitting material in an OLED device, and the structure is represented as follows: on glass containing ITO, the hole injection layer (HIL) is HT-1:P-3 (95:5 v / v%), with a thickness of 10 nm; the hole transport layer (HTL) is HT-1, with a thickness of 90 nm; the electron blocking layer (EBL) is HT-10, with a thickness of 10 nm, the light-emitting layer (EML) is the host material (H-1 or H-2 or H-3 or H-4 or H-5 or H-6): the platinum metal complex of the present invention (95:5 v / v%), with a thickness of 35 nm, the electron transport layer (ETL) is ET-13:LiQ (50:50 v / v%), with a thickness of 35 nm, and then the cathode Al is evaporated to 70 nm.

[0154]

[0155] The fabricated organic light-emitting device was tested under standard conditions well-known in the art. Among them, the maximum external quantum efficiency (EQE) of a device using Pt(bp-1-m-t) as the light-emitting material reached 19.5%.

[0156] It should be noted that the described structure is an example of an application of the present invention's tetradentate fused-ring 6 / 5 / 6 platinum(II) complex phosphorescent material based on spirofluorene-biphenyl-acridine, and does not constitute a limitation on the specific OLED device structure of the luminescent material shown in the present invention. The luminescent material is also not limited to the compounds shown in the examples.

[0157] Those of ordinary skill in the art can understand that the above-described embodiments are specific examples for implementing the present invention, and in actual applications, various changes can be made to them in form and details without departing from the spirit and scope of the present invention. For example, many of the substituent structures described here can be replaced with other structures without departing from the spirit of the present invention.

Claims

1. A tetradentate fused-ring 6 / 5 / 6 platinum(II) complex phosphorescent material based on spirofluorene-biphenyl-acridine, wherein, The tetradentate fused-ring 6 / 5 / 6 platinum(II) complex phosphorescent material has one of the following structures:

2. Application of the tetradentate fused-ring 6 / 5 / 6 platinum(II) complex phosphorescent material based on spirofluorene-biphenyl-acridine described in claim 1 in a light-emitting device.

3. The application according to claim 2, wherein Wherein the light-emitting device is a light-emitting diode or a light-emitting electrochemical cell.

4. The application according to claim 2 or 3, characterized in that The light-emitting device includes a first electrode, a second electrode, and at least one organic layer disposed between the first electrode and the second electrode, and at least one of the organic layers includes the tetradentate fused-ring 6 / 5 / 6 platinum(II) complex phosphorescent material based on spirofluorene-biphenyl-acridine described in claim 1.

5. A light-emitting display device, characterized in that, Comprising an organic light-emitting device, the organic light-emitting device comprising a light-emitting layer made of the tetradentate fused-ring 6 / 5 / 6 platinum(II) complex phosphorescent material based on spirofluorene-biphenyl-acridine described in claim 1.

6. A display device, characterized in that, Including an organic light-emitting device, wherein the organic light-emitting device includes a first electrode, a second electrode, and at least one organic layer disposed between the first electrode and the second electrode, and at least one of the organic layers includes the tetradentate fused-ring 6 / 5 / 6 platinum(II) complex phosphorescent material based on spirofluorene-biphenyl-acridine described in claim 1.

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