Organic metal complex luminescent material and organic electroluminescent device comprising same

Abstract

The invention belongs to the field of organic photoelectric materials, and discloses an organic metal complex luminescent material and an organic electroluminescent device containing the organic metal complex luminescent material. The organometallic complex luminescent material has a composition of formula M (LA) m (LB) n, wherein LB is a bidentate ligand; and m is 1, 2 or 3; n is 0, 1 or 2; m + n is the oxidation state of the metal M; the structures of the first ligand LA and the second ligand LB are shown in the specification. The organic electroluminescent device prepared by taking the organic metal complex luminescent material provided by the invention as a luminescent layer doping material has relatively low driving voltage, relatively good luminous efficiency and longer service life.

Description

Technical Field

[0001] This invention belongs to the field of organic optoelectronic materials, and relates to organic synthesis and related applications of organic electroluminescent materials. More specifically, it relates to the preparation and devices of organometallic complex doped materials in organic light-emitting diodes, related electronic devices, and consumer products. Background Technology

[0002] Organic light-emitting diodes (OLEDs), as a next-generation display and lighting technology, have become a core development direction in the display field due to their self-emissive, high-contrast, wide color gamut, and flexible characteristics. Currently, performance improvements in OLED devices heavily rely on innovation in luminescent materials. Organometallic compounds, with their advantages of high luminous efficiency and easily tunable emission colors, have become a key research focus for red, green, and blue primary color materials. Especially in the field of full-color displays, the development of high-performance green and red light-emitting materials is a crucial step in achieving high color gamut and long-life OLED devices, and their performance directly affects the display effect and market competitiveness of end products.

[0003] The luminescence properties of organometallic complexes are closely related to their molecular structure. Metal ions (such as iridium and platinum) bind to organic ligands through coordination bonds, forming a unique charge-transfer structure. In this structure, the d orbitals of the metal ion and the π orbitals of the ligand undergo energy level coupling, significantly enhancing spin-orbit interactions. This interaction breaks the ratio limitation of singlet excitons (25%) to triplet excitons (75%) in electroluminescence, allowing triplet excitons to release energy through radiative transitions, thereby greatly improving luminescence efficiency (theoretically up to 100%). By controlling the conjugation length of the ligands and the type of substituents, precise control of the material's emission wavelength can be achieved, thus obtaining luminescence in specific wavelength bands such as green and red light.

[0004] While organometallic complexes for green and red light emission, as core materials for the three primary colors of OLEDs, have achieved industrial application, performance shortcomings remain. Green light materials suffer from rapid efficiency degradation after long-term operation in large-size devices, insufficient stability at high temperatures, and some novel green light materials are difficult to mass-produce due to complex synthesis processes and high costs. Red light materials generally face a trade-off between efficiency and color purity, poor stability, and susceptibility to exciton quenching in devices. Therefore, there is still significant room for development in green and red light emission materials. Summary of the Invention

[0005] In view of this, the present invention provides an organometallic complex luminescent material and an organic electroluminescent device comprising the same. Organic electroluminescent devices prepared using the organometallic complex luminescent material provided by the present invention as the dopant material for the luminescent layer exhibit relatively low driving voltage, good luminous efficiency, and longer service life.

[0006] To achieve the above objectives, the following technical solution is adopted:

[0007] The first technical objective of this invention is to provide an organometallic complex luminescent material having the formula M(L A ) m (L B ) n The composition of L B It is a bidentate ligand; and m is 1, 2, or 3; n is 0, 1, or 2; m+n is the oxidation state of metal M; the first ligand L A It has the structure shown in Equation I:

[0008]

[0009] First ligand L A It can coordinate with metal M, and metal M can coordinate with other ligands, wherein metal M can be Ir, Cu, Pt, Ag or Au.

[0010] Furthermore, the metal M is Ir.

[0011] In Formula I, ring H1 and ring H2 are independently selected from monocyclic or polycyclic systems, wherein the monocyclic ring is a five- to ten-membered carbon ring or heterocyclic ring; wherein the heteroatom in the heterocyclic ring is one or more combinations of O, S, N, P, B, Si, and Ge;

[0012] X1 to X4 are each independently selected from C or N;

[0013] K1 is selected from the following structures: single bond, BR, BRR', NR, PR, P(O)R, O, S, Se, C=O, C=S, C=Se, C=NR, C=CRR', S=O, SO2, CRR', SiRR', and GeRR';

[0014] K2 and K3 are independently selected from the following structures: single bond, O, S, N(S) a ), P(S a ), B(S a ), C(S a (S) b ) and Si(S) a (S) b );

[0015] R a and R b Substituents on ring H1 and ring H2 can be represented as 0 to the maximum allowable substitution on the ring;

[0016] In R a and R b In this context, at least one of the following structures (Formula II) must be selected:

[0017]

[0018] In Formula II, X is either Si or Ge;

[0019] R, R', S a S b R a R b R1, R2, R3, R4, and R5 are each independently selected from hydrogen, deuterium, cyano, halogen, carboxyl, and substituted or unsubstituted C1-C6 groups. 60 Alkyl, substituted or unsubstituted C3-C 60 Cycloalkyl, substituted or unsubstituted C1-C 60 Heteroalkyl, substituted or unsubstituted C3-C 60 Heterocyclic alkyl, substituted or unsubstituted C1-C 60 Alkoxy, amino, substituted or unsubstituted C3-C 60 Silyl, substituted or unsubstituted C3-C 60 germanyl, boronyl, substituted or unsubstituted C2-C 60 Alkenyl, substituted or unsubstituted C3-C 60 Cycloalkenyl, substituted or unsubstituted C2-C 60 Heterene, substituted or unsubstituted C2-C 60 Alkyne group, substituted or unsubstituted C6-C 60 Aryl, substituted or unsubstituted C4-C 60 Heteroaryl, acyl, ester, isonitrile, thio, sulfinyl, sulfonyl, phosphinyl, selenyl.

[0020] Furthermore, R, R', S a S b R a R b R1, R2, R3, R4, and R5 can be partially or completely replaced by deuterium, cyano, carboxyl, halogen, or substituted or unsubstituted C1-C6 groups. 30 Alkyl, substituted or unsubstituted C3-C 30 Cycloalkyl, substituted or unsubstituted C1-C 30 Heteroalkyl, substituted or unsubstituted C3-C 30 Heterocyclic alkyl, substituted or unsubstituted C1-C 30 Alkoxy, amino, substituted or unsubstituted C3-C 30 Silyl, substituted or unsubstituted C3-C 30 germanyl, boronyl, substituted or unsubstituted C2-C 30 alkenyl, substituted or unsubstituted C3-C 30 Cycloalkenyl, substituted or unsubstituted C2-C 30Heterene, substituted or unsubstituted C2-C 30 Alkyne group, substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C4-C 30 Heteroaryl, acyl, ester, isonitrile, thio, sulfinyl, sulfonyl, phosphinyl, selenyl.

[0021] Furthermore, R, R', S a S b R a R b The heteroatoms in R1, R2, R3, R4, and R5 can be one or more combinations of O, S, Se, N, P, B, Si, and Ge; in R, R', and S a S b R a R b In this context, two adjacent substituents can connect to form a ring, which can be a carbocyclic or heterocyclic ring. The heteroatom can be one or more combinations of O, S, N, P, B, Si, and Ge. Boroalkyl refers to a group formed when at least one hydrogen atom in a borane is substituted, and this substituent can be related to R, R', or S. a S b R a R b The ranges defined by R1, R2, R3, R4, and R5 are the same.

[0022] Furthermore, R, R', S a S b R a R b When R1, R2, R3, R4, and R5 are alkyl groups, they are preferably C1-C6. 10 Alkyl groups, including methyl, ethyl, propyl, butyl, tert-butyl, 2-methylpropyl, pentyl, 1-methylpropyl, and 2,2-dimethylpropyl; R, R', S a S b R a R b When R1, R2, R3, R4, and R5 are cycloalkyl groups, C3-C4 is preferred. 12 Cycloalkyl groups, including monocyclic and spirocyclic groups, specifically cyclopropane, cyclopentane, cyclohexane, cycloheptane, spiro[4.5]decyl, spiro[5.5]undecyl; R, R', S a S b R a R b When R1, R2, R3, R4, and R5 are heteroalkyl groups, they are preferably C1-C1. 10Heteroalkyl, which refers to an alkyl group in which at least one carbon atom is replaced by a heteroatom, preferably O, S, and N; R, R', S a S b R a R b When R1, R2, R3, R4, and R5 are heterocyclic alkyl groups, the heteroatom can be one or more combinations of O, S, N, P, B, Si, Ge, and Se, wherein the heterocyclic alkyl group is preferably C3-C4. 10 Heterocyclic alkyl groups, including cycloamino, morpholino, piperidinyl, pyrrolyl, cyclohexyl ether, thioether, tetrahydrofuran, tetrahydropyran, and tetrahydrothiophene; R, R', S a S b R a R b When R1, R2, R3, R4, and R5 are alkoxy groups, C1-C4 alkoxy groups are preferred, including methoxy, ethoxy, propoxy, butoxy, and tert-butyloxy groups; R, R', and S a S b R a R b When R1, R2, R3, R4, and R5 are silane-based, C3-C is preferred. 18 Silyl groups, including trimethylsilyl, triethylsilyl, tri-tert-butylsilyl, tert-butyldimethylsilyl, tert-butyldiethylsilyl, triphenylsilyl, phenyldimethylsilyl, and diphenylmethylsilyl, with trimethylsilyl and tert-butyldimethylsilyl being more preferred; R, R', S a S b R a R b When R1, R2, R3, R4, and R5 are germanyl groups, C3-C is preferred. 18 Silyl groups, including trimethylgermanium, triethylgermanium, tri-tert-butylgermanium, tert-butyldimethylgermanium, tert-butyldiethylgermanium, triphenylgermanium, phenyldimethylgermanium, and diphenylmethylgermanium, with trimethylgermanium and tert-butyldimethylgermanium being more preferred; R, R', S a S b R a R b When R1, R2, R3, R4, and R5 are alkenyl, cycloalkenyl, and heteroalkenyl groups, they refer to groups whose alkyl, cycloalkyl, and heteroalkyl structures contain at least one carbon-carbon double bond, wherein the heteroatom is one or more combinations of O, S, N, P, B, Si, Ge, and Se; R, R', and S a S b R a R bWhen R1, R2, R3, R4, and R5 are alkynyl groups, they refer to groups whose alkyl structure contains at least one carbon-carbon triple bond; R, R', and S a S b R a R b When R1, R2, R3, R4, and R5 are aryl groups, C6-C is preferred. 24 Aryl groups, including phenyl, naphthyl, anthracene, diphenyl, terphenyl, fluorene, and triphenylene; R, R', R a R b R a R b When R1, R2, R3, R4, and R5 are heteroaryl groups, C4-C is preferred. 30 Heteroaryl groups include furan, thiophene, benzofuran, benzothiophene, dibenzofuran, dibenzothiophene, carbazole, selenophene, benzoselenophene, dibenzoselenophene, pyridine, imidazole, oxazole, thiazole, oxadiazole, dioxazole, pyridazine, pyrimidine, pyrazine, triazine, indole, benzimidazole, benzoxazole, benzothiazole, quinoline, isoquinoline, benzofuran-pyridine, furan-dipyridine, benzothiophene-pyridine, thiophene-dipyridine, azirone, cycloborane; more preferably benzofuran, benzothiophene, dibenzofuran, dibenzothiophene, carbazole, imidazole, pyridine, indole-carbazole, triazine, benzimidazole.

[0023] Furthermore, ring H1 and ring H2 are each independently selected from the following structures: benzene, pyridine, pyrimidine, pyridazine, pyrazine, triazine, imidazole, imidazole-derived carbenes, pyrazole, pyrrole, oxazole, furan, thiophene, thiazole, triazole, naphthalene, quinoline, isoquinoline, quinazoline, benzofuran, aza-benzofuran, benzoxazole, aza-benzoxazole, benzothiophene, aza-benzothiophene, benzothiazole, aza-benzothiazole, benzoselenene, aza-benzoselenene. Indene, aza-indene, indole, aza-indole, benzimidazole, benzimidazole-derived carbenes, aza-benzimidazole, aza-benzimidazole-derived carbenes, naphtho-imidazolium, aza-naphtho-imidazolium, carbazole, aza-carbazole, dibenzofuran, aza-dibenzofuran, phenanthrene[3,2-b]benzofuran, dibenzothiophene, aza-dibenzothiophene, quinoxaline, phthalazine, phenanthrene, aza-phenanthrene, anthracene, aza-anthracene, phenanthridine, fluorene, and aza-fluorene.

[0024] Furthermore, Equation II can be selected from the following structures:

[0025]

[0026] Furthermore, Formula II can preferably have the following structure:

[0027]

[0028] Furthermore, the first ligand L A The following structures can be selected:

[0029]

[0030]

[0031]

[0032]

[0033]

[0034] Where, formula L A -1 to formula L A -123 The alphanumeric codes in each structure are independent of other structures and only meaningful within that structure; the alphanumeric codes refer to Y1, Y2, P1~P 19 P a P b R c R d R e R f R j R h R i r1, r2, r3, r4, Q1;

[0035] Where Q1 is B;

[0036] Y1, Y2, P a P b They are one of B, N, P, O, S, Se, Si, and Ge, respectively.

[0037] P1~P 19 They are selected independently from C and N respectively;

[0038] R c R d R e R f R j R h R i The range of substituents defined by r1, r2, r3, and r4 is related to R. a R b The defined range of substituents is consistent;

[0039] K 3' It is selected from one of the following: single bond, O, S, N, P, B, C, and Si.

[0040] Furthermore, the first ligand L A The following structures can be preferred:

[0041]

[0042]

[0043]

[0044]

[0045]

[0046] The scope defined by the substituents mentioned above is the same as that described above, and will not be repeated here.

[0047] The structural formula of the organometallic complex luminescent material may include the following: M(L A )1(L B1 )2、M(L A )2(L B2 1. When the structural formula is M(L) A )1(L B1 At 2, the second ligand L B1 It has the following general formula structure:

[0048]

[0049] R m and R n The substituent-defined range is the same as that of the aforementioned L. A The ranges defined by R1 and R2 in the ligands are the same;

[0050] Furthermore, the second ligand L B1 The following structures are preferred:

[0051]

[0052]

[0053] When the structural formula is M(L) A )2(L B2 At 1, the second ligand L B2 It has the following general formula structure:

[0054]

[0055] R o R p R q The substituent-defined range is the same as that of the aforementioned L. A The ranges defined by R1 and R2 in the ligands are the same;

[0056] Furthermore, the second ligand L B2 The following structures are preferred:

[0057]

[0058]

[0059] Furthermore, the organometallic complex luminescent material has the following structure:

[0060]

[0061]

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068]

[0069]

[0070]

[0071]

[0072]

[0073]

[0074]

[0075]

[0076]

[0077]

[0078]

[0079]

[0080]

[0081]

[0082]

[0083]

[0084]

[0085]

[0086]

[0087]

[0088]

[0089]

[0090]

[0091]

[0092]

[0093]

[0094]

[0095]

[0096]

[0097]

[0098]

[0099]

[0100]

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107]

[0108]

[0109]

[0110]

[0111]

[0112]

[0113] This invention also claims protection for a method for preparing an organometallic complex luminescent material as described above, the synthesis steps and general formula of which are as follows:

[0114] 1. In a three-necked flask, solvent and formula I-a and formula I-b are added, nitrogen is purged, a catalyst is added under a nitrogen atmosphere, and the reaction is carried out under certain conditions. After the reaction is completed, the compound with the formula I structure is obtained by column chromatography.

[0115] 2. Add ethylene glycol ethyl ether and water to a three-necked flask, and then add formula L. B1 The ligand was added to the reaction system, nitrogen gas was purged, and then iridium trichloride was added. The reaction was refluxed under nitrogen protection, and then cooled to room temperature. A precipitate formed, which was filtered, washed sequentially with water, anhydrous ethanol, and petroleum ether, and dried to obtain formula L. B1 Ligand 1;

[0116] 3. Weigh L B1 Ligand 1 was added to the system, followed by dichloromethane and silver trifluoromethanesulfonate dissolved in methanol. After purging with nitrogen, the reaction was carried out at room temperature. Finally, the mixture was subjected to column chromatography (short column), and the filtrate was concentrated to a solid to obtain the iridium complex L. B1 Ligand 2;

[0117] 4. Weighing formula L B1 Ligand 2 was added to the compound with the structure shown in Formula I, and then anhydrous ethanol was added to the system. After replacing the nitrogen gas, the reaction was carried out at a certain temperature, then filtered, washed with alcohol, and dried to obtain the crude product. Finally, dichloromethane and petroleum ether were used as eluents, and silica gel column chromatography was used to obtain the final product compound with the structure shown in Formula 1.

[0118] The synthesis route is as follows:

[0119]

[0120] In this invention, another method for preparing organometallic complex luminescent materials includes the following synthesis steps:

[0121] 1. The preparation method of Formula I is the same as the preparation method described above, and will not be repeated here;

[0122] 2. Add ethylene glycol ethyl ether and water to a three-necked flask, add Formula I to the reaction system, replace with nitrogen, then add iridium trichloride, and reflux at 120°C for 48 h under nitrogen protection; after the reaction is completed, cool to room temperature, then filter by suction, wash with anhydrous ethanol and petroleum ether in sequence, and finally dry to obtain Formula I-1;

[0123] 3. Add ethylene glycol ethyl ether to a three-necked flask, add Formula I-1 to the reaction system, displace the nitrogen gas, and then add L. B2 The ligand was refluxed at 120°C for 48 h under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature, and the precipitate was filtered, washed with anhydrous ethanol and dried to obtain the compound with the structure shown in product 2.

[0124] Synthesis route:

[0125]

[0126] According to the present invention, an organic electroluminescent device is also provided, the organic electroluminescent device comprising an anode, a cathode, and an organic functional layer disposed between the anode and the cathode, the organic functional layer comprising a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer; the light-emitting layer comprises a host material and a dopant material, the dopant material comprising the organometallic complex light-emitting material as described above.

[0127] The anode materials can be divided into two main categories. The first category is traditional anode materials, such as indium tin oxide (ITO), indium zinc oxide (IZO), gold (Au), silver (Ag), etc. The second category is novel anode materials, such as poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid (PEDOT:PSS), polyaniline (PANI), graphene composite electrodes, etc.

[0128] The materials used for the hole injection layer and the hole transport layer are not limited and can be phthalocyanine derivatives, indolocarbazole derivatives, polymers containing fluorinated hydrocarbons, conductive polymers, or polymers containing conductive dopants, such as polyphenylene ethylene, polyaniline / dodecylbenzenesulfonic acid, poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate), polyaniline / camphor sulfonic acid, polyaniline / poly(4-styrenesulfonate), aromatic amine derivatives, etc.

[0129] The electron blocking layer can be used to reduce the number of electrons and / or excitons leaving the emission layer. The materials used can be organic small molecule materials, metal oxides, inorganic salts, polymers, silicon-based and novel materials, as well as quantum dot materials, such as NPB, TCTA, MoO3, WO3, CsF, CsCO3, poly(3,4-ethylenedioxythiophene):polystyrene sulfonate, etc.

[0130] The light-emitting layer comprises a host material and a dopant material. The host material provides a carrier transport channel, while the dopant material improves luminescence efficiency. Generally, these are red, green, or blue phosphorescent materials; for example, in this application, the metal complex luminescent material is the dopant material. The host material can be a single type, an excimer compound, a polymer, or a TADF material. Single-type materials include CBP, mCP, TCTA, and Alq3; excimer compound materials include mCP:PO-T2T; and polymeric materials include polyfluorene and poly(p-styrene) derivatives.

[0131] The hole blocking layer can be used to reduce the number of holes and / or excitons leaving the emitter layer. The materials used can be organic small molecule materials, n-type polymer materials, metal oxides and composite material systems, such as TPBi, BCP, 1,10-phenanthroline, n-type polythiophene derivatives, titanium dioxide, etc.

[0132] The materials used in the electron transport layer and electron injection layer are unrestricted and can be of the same type. The materials can be a single compound or a combination of multiple compounds, such as Alq3 (tris(8-hydroxyquinoline)aluminum), Znq (tris(8-hydroxyquinoline)zinc), Bebq2 (bis(10-hydroxybenzo[h]quinoline)beryllium), TPBi (1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene), Bphen (4,7-diphenyl-1,10-phenanthroline), TAZ (1,2,4-triazole derivative), or polyfluorene derivatives and poly(p-styrene).

[0133] In one embodiment of the present invention, the cathode material includes metals or alloys such as magnesium (Mg), silver (Ag), aluminum (Al), lithium aluminum (Al-Li), calcium (Ca), magnesium-indium (Mg-In), and magnesium-silver (Mg-Ag), as well as any combination thereof.

[0134] Compared with the prior art, the present invention has the following beneficial effects:

[0135] This invention provides an organometallic complex luminescent material, prepared by introducing a special structure containing silicon or germanium atoms into the structure, followed by reaction with a metal and other monomers. The introduction of silicon or germanium modifying groups in this material optimizes electron mobility, thin-film conductivity, and interfacial properties, while silicon or germanium exhibits good stability. Therefore, the organometallic complex luminescent material provided by this invention possesses good luminous efficiency, optimal driving voltage, and long lifespan. Attached Figure Description

[0136] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0137] Figure 1 This is the hydrogen nuclear magnetic resonance spectrum of compound formula 20-184 in Example 1 of the present invention.

[0138] Figure 2 This is the hydrogen nuclear magnetic resonance spectrum of compound formula 87-721 in Example 2 of the present invention. Detailed Implementation

[0139] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments and related drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0140] Additionally, it should be noted that the values ​​given in the following embodiments are as accurate as possible. However, those skilled in the art will understand that due to unavoidable measurement errors and experimental issues, each number should be understood as an approximation rather than an absolutely accurate value.

[0141] Example 1

[0142] The specific synthesis steps for synthesizing the metal complex luminescent material, formula 20-184, are as follows:

[0143] 1. Synthesis of Intermediate 1

[0144] In a three-necked flask, reactant 1 (1 eq) (CAS No.: 2458817-55-3), pinacol diborate (2 eq), and potassium acetate (2.5 eq) were added. Then, 1,4-dioxane was added as a solvent. After purging with nitrogen twice, DBA palladium (0.02 eq) and X-phos (0.08 eq) were added, followed by purging with nitrogen once more. The mixture was reacted at 80 °C for 24 h. After cooling to room temperature, reactant 2 (yield: 85.6%) was obtained by rotary evaporation, passing the solution through a silica gel funnel, and then rotary evaporation again.

[0145] In a three-necked flask, reactant 2 (1.2 eq), reactant 3 (CAS No.: 1093241-27-0) (1 eq), and anhydrous potassium carbonate (3 eq) were added. Then, toluene, ethanol, and water in a volume ratio of 2:1:1 were added as solvents. After purging with nitrogen twice, Pd(pph3)4 (0.03 eq) was added, and nitrogen was purged once more. The reaction was carried out at 100 °C for 24 h. After cooling to room temperature, the mixture was purified by column chromatography (eluent: dichloromethane and petroleum ether) to obtain intermediate 1 (yield: 68.4%).

[0146]

[0147] 2. Synthesis of intermediate 2

[0148]

[0149] Reactant 4 (CAS: 92646-00-9) (2.5 eq) and IrCl3·3H2O (1 eq) were placed in a three-necked flask, and then 15 times the mass of reactant 4 in ethylene glycol ethyl ether and 3 times the mass of purified water were added. After purging with nitrogen twice, the mixture was refluxed at 120°C for 48 hours. After cooling to room temperature, a precipitate was formed. The precipitate was filtered, washed with anhydrous ethanol and petroleum ether in sequence, and dried to obtain the bridged ligand reactant 5 shown, with a yield of 59.1%.

[0150] The reactant 5 (1 eq) and silver trifluoromethanesulfonate (2.2 eq) were weighed and added to a three-necked flask. Then, 20 times the mass of reactant 5 in dichloromethane and 3 times the mass of methanol were added to the system. The reaction was carried out at room temperature for 48 hours under nitrogen protection. The iridium complex intermediate 2 was then purified and concentrated through a silica gel funnel, with a yield of 62.5%.

[0151] 3. Synthesis of Equation 20-184

[0152]

[0153] Weigh intermediate 2 (1 eq) and intermediate 1 (2.5 eq) into a three-necked flask, then add anhydrous ethanol as solvent to the system, replace with nitrogen twice, reflux at 80 °C for 48 hours, cool to room temperature, filter, wash with alcohol, dry, and obtain formula 20-184 by column chromatography (eluent: dichloromethane and petroleum ether) (yield: 32.3%, HPLC: greater than 99%).

[0154] Mass spectrometry test value: 996.85.

[0155] Elemental analysis results: C: 64.83, H: 5.67, N: 5.69, O: 1.72, Si: 2.89.

[0156] NMR data such as Figure 1 As shown.

[0157] Example 2

[0158] The synthetic metal complex luminescent material, formula 87-721, is synthesized using the following steps:

[0159] 1. Synthesis of intermediate 3

[0160] In a three-necked flask, 15 times the mass of reactant 6 in tetrahydrofuran was added, followed by reactant 6 (1 eq) (CAS No.: 1235872-86-2). After purging with nitrogen twice, the mixture was cooled to -78°C using liquid nitrogen, and then n-BuLi (1.1 eq) was slowly added dropwise. After the addition was complete, the mixture was stirred for 0.5 h. Under a nitrogen atmosphere, a tetrahydrofuran solution of tert-butyldimethylchlorosilane (1.3 eq) (CAS No.: 18162-48-6) was added dropwise, and the mixture was slowly heated to room temperature and reacted for 1.5 h. After the reaction was complete, a saturated sodium bicarbonate solution was added to remove acid, and then reactant 7 was obtained by separation, rotary evaporation, and column chromatography, with a yield of 86.2%.

[0161]

[0162] Reactant 7 (1 eq), pinacol diborate (2 eq), and potassium acetate (2.5 eq) were added to a three-necked flask. Then, 1,4-dioxane (20 times the mass of reactant 7) was added as a solvent. After purging with nitrogen twice, DBA palladium (0.02 eq) and X-phos (0.08 eq) were added, followed by another purging with nitrogen. The mixture was reacted at 80 °C for 24 h. After cooling to room temperature, reactant 8 was obtained by rotary evaporation, passing the solution through a silica gel funnel, and then rotary evaporation again. The yield was 87.8%.

[0163] In a three-necked flask, reactant 8 (1.2 eq), reactant 1-tert-butyl-6-chloronaphthalene (source: US12030853B2) (1 eq) and anhydrous potassium carbonate (3 eq) were added. Then, toluene (20 times the mass of 1-tert-butyl-6-chloronaphthalene), ethanol (10 times the mass of ethanol), and water were added as solvents. After purging with nitrogen twice, Pd(pph3)4 (0.03 eq) was added, and nitrogen was purged once more. The reaction was carried out at 100 °C for 24 h. After cooling to room temperature, the mixture was purified by column chromatography (eluent: dichloromethane and petroleum ether) to obtain intermediate 3 (yield: 63%).

[0164] 2. Synthesis of intermediate 4

[0165]

[0166] In a three-necked flask, 15 times the mass of intermediate 3 (ethylene glycol ethyl ether) and 3 times the mass of water were added, followed by intermediate 3. After purging with nitrogen twice, iridium trichloride was added, and the mixture was refluxed at 120°C for 48 hours under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature, filtered, and washed successively with anhydrous ethanol and petroleum ether. Finally, it was dried to obtain intermediate 4, with a yield of 53.5%.

[0167] 3. Synthesis of Equation 87-721

[0168]

[0169] Add 10 times the mass of intermediate 4 to a three-necked flask containing ethylene glycol ethyl ether, then add intermediate 4, purge twice with nitrogen, and then add formula L. B2 -6, and then reacted at 120°C for 48 h under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature, the precipitate was filtered, washed with anhydrous ethanol and dried to give the compound with the structure shown in Formula 87-721. (Yield: 31.7%, HPLC: greater than 99%).

[0170] Mass spectrometry value: 1396.94.

[0171] Elemental analysis

[0172] Test values: C: 65.89, H: 7.16, N: 2.09, O: 2.37, S: 4.72, Si: 4.11.

[0173] NMR data such as Figure 2 As shown.

[0174] The synthesis methods for other compounds are the same as those described above, and will not be repeated here.

[0175] Device fabrication example 1

[0176] The compound with the structure shown in Formula 20-184 prepared in Example 1 was used as a dopant in an organic electroluminescent device. The preparation method is as follows:

[0177] 1. On the anode, the ITO patterned glass substrate is cut into a size of 50mm×50mm×0.5mm, cleaned three times with detergent for 5 minutes each time, then ultrasonically treated with isopropanol and acetone for 10 minutes in sequence, dried with nitrogen, and finally exposed to ultraviolet light and ozone for 30 minutes.

[0178] 2. The obtained glass substrate is loaded onto a vacuum deposition apparatus. First, Formula A is deposited on the anode as a hole injection layer with a thickness of 100 angstroms. Then, the first hole layer, Formula C, is deposited with a thickness of 600 angstroms. Next, the electron blocking layer, Formula D, is deposited with a thickness of 50 nm. The structural formulas of Formulas A, C, D, and E are as follows:

[0179]

[0180] 3. Using the host material 4,4'-bis(N-carbazolyl)1,1'-biphenyl (CBP) and the compound with the structure shown in Formula 20-184 prepared in Example 1 as dopants, a light-emitting layer was prepared at a mass ratio of 95:5, with a deposition thickness of 400 Å. Then, a TPBI (Formula E) electron transport layer with a thickness of 400 Å was deposited on the light-emitting layer, a LiF electron injection layer with a thickness of 10 Å was deposited on the electron transport layer, and finally, a cathode material Al with a thickness of 1500 Å was deposited on the electron injection layer to obtain the organic electroluminescent device.

[0181] Referring to Device Fabrication Example 1, the compound with the structure shown in Formula 20-184 was replaced with compounds of formulas 20-186, 20-190, 20-192, 20-196, 20-201, 25-205, 24-211, 24-215, 26-238, 26-248, 87-721, 51-472, 51-474, 51-476, 51-481, 52-488, 87-722, 87-723, and 88-724, and these were used as dopants in organic electroluminescent devices, respectively. This is referred to as Device Fabrication Example 2-20, and details are shown in Tables 1 and 2.

[0182] Device Comparison Examples 1-10

[0183] Organic electroluminescent devices were prepared using the same method as in Device Preparation Example 1, except that the doping material in the light-emitting layer, Formula 20-184, was replaced with Compound 1 to Compound 10, to obtain Device Comparative Examples 1-10.

[0184] The structures of compounds 1 through 10 are shown below:

[0185]

[0186] To further illustrate the luminescent properties of the organometallic complex luminescent materials prepared in this invention, the luminescent characteristics of the organic light-emitting devices prepared in Device Preparation Examples 1-20 and the devices obtained in Device Comparative Examples 1-10 were tested. The measurements were performed using a KEITHLEY 2400 source measurement unit and a CS-2000 spectroradiometer to evaluate the driving voltage, luminescent efficiency, and lifetime. The results were based on the results of Device Comparative Examples 1 and 6, and are shown in Tables 1 and 2.

[0187] Table 1. Luminescence detection data of organic electroluminescent devices

[0188]

[0189]

[0190] Table 2. Luminescence detection data of organic electroluminescent devices

[0191]

[0192] As shown in Tables 1 and 2, when the luminous intensity is 8000, compared with Comparative Examples 1-5 and 12-20, the luminous efficiency and lifetime of Device Examples 1-11 are longer, while the driving voltage is lower. This may be because the direct silicon-silicon or silicon-germanium bonding modification substituents affect carrier transport, leading to interface energy level mismatch and interface defects, thus affecting device efficiency. On the other hand, the direct silicon-silicon or silicon-germanium bonding modification substituents can increase the interface barrier and cause chemical degradation, thereby affecting the driving voltage and lifetime.

[0193] Therefore, organic electroluminescent devices prepared using the compounds provided in this invention as doping materials for the light-emitting layer have relatively low driving voltage, good luminous efficiency, and longer service life.

[0194] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An organometallic complex luminescent material, characterized in that, The organometallic complex luminescent material has the formula M(L) A ) m (L B ) n The composition of L B It is a bidentate ligand; and m is 1, 2, or 3; n is 0, 1, or 2; m+n is the oxidation state of metal M; the first ligand L A It has the structure shown in Equation I: First ligand L A It can coordinate with metal M, and metal M can coordinate with other ligands, wherein metal M can be Ir, Cu, Pt, Ag or Au; In Formula I, ring H1 and ring H2 are independently selected from monocyclic or polycyclic systems, wherein the monocyclic ring is a five- to ten-membered carbon ring or heterocyclic ring; wherein the heteroatom in the heterocyclic ring is one or more combinations of O, S, N, P, B, Si, and Ge; X1 to X4 are each independently selected from C or N; K1 is selected from the following structures: single bond, BR, BRR', NR, PR, P(O)R, O, S, Se, C=O, C=S, C=Se, C=NR, C=CRR', S=O, SO2, CRR', SiRR', and GeRR'; K2 and K3 are independently selected from the following structures: single bond, O, S, N(S) a ), P(S a ), B(S a ), C(S a (S) b ) and Si(S) a (S) b ); R a and R b Substituents on ring H1 and ring H2 can be represented as 0 to the maximum allowable substitution on the ring; In R a and R b In this context, at least one of the following structures (Formula II) must be selected: In Formula II, X is either Si or Ge; R, R', S a S b R a R b R1, R2, R3, R4, and R5 are each independently selected from hydrogen, deuterium, cyano, halogen, carboxyl, and substituted or unsubstituted C1-C6 groups. 60 Alkyl, substituted or unsubstituted C3-C 60 Cycloalkyl, substituted or unsubstituted C1-C 60 Heteroalkyl, substituted or unsubstituted C3-C 60 Heterocyclic alkyl, substituted or unsubstituted C1-C 60 Alkoxy, amino, substituted or unsubstituted C3-C 60 Silyl, substituted or unsubstituted C3-C 60 germanyl, boronyl, substituted or unsubstituted C2-C 60 Alkenyl, substituted or unsubstituted C3-C 60 Cycloalkenyl, substituted or unsubstituted C2-C 60 Heterene, substituted or unsubstituted C2-C 60 Alkyne group, substituted or unsubstituted C6-C 60 Aryl, substituted or unsubstituted C4-C 60 The heteroatom can be one or more combinations of O, S, Se, N, P, B, Si, and Ge.

2. The organometallic complex luminescent material according to claim 1, characterized in that, R, R', S a S b R a R b R1, R2, R3, R4, and R5 can be partially or completely replaced by deuterium, cyano, carboxyl, halogen, or unsubstituted C1-C6 groups. 30 Alkyl, substituted or unsubstituted C3-C 30 Cycloalkyl, substituted or unsubstituted C1-C 30 Heteroalkyl, substituted or unsubstituted C3-C 30 Heterocyclic alkyl, substituted or unsubstituted C1-C 30 Alkoxy, amino, substituted or unsubstituted C3-C 30 Silyl, substituted or unsubstituted C3-C 30 germanyl, boronyl, substituted or unsubstituted C2-C 30 alkenyl, substituted or unsubstituted C3-C 30 Cycloalkenyl, substituted or unsubstituted C2-C 30 Heterene, substituted or unsubstituted C2-C 30 Alkyne group, substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C4-C 30 Heteroaryl, acyl, ester, isonitrile, thio, sulfinyl, sulfonyl, phosphin, selenyl.

3. The organometallic complex luminescent material according to claim 1 or 2, characterized in that, R, R', S a S b R a R b When R1, R2, R3, R4, and R5 are alkyl groups, they are preferably C1-C6. 10 Alkyl groups, including methyl, ethyl, propyl, butyl, tert-butyl, 2-methylpropyl, pentyl, 1-methylpropyl, and 2,2-dimethylpropyl; R, R', S a S b R a R b When R1, R2, R3, R4, and R5 are cycloalkyl groups, they are preferably C3-C4. 12 Cycloalkyl groups, including monocyclic and spirocyclic groups, specifically cyclopropane, cyclopentane, cyclohexane, cycloheptane, spiro[4.5]decyl, spiro[5.5]undecyl; R, R', S a S b R a R b When R1, R2, R3, R4, and R5 are heteroalkyl groups, they are preferably C1-C1. 10 Heteroalkyl, which refers to an alkyl group in which at least one carbon atom is replaced by a heteroatom, preferably O, S, and N; R, R', S a S b R a R b When R1, R2, R3, R4, and R5 are heterocyclic alkyl groups, the heteroatom can be one or more combinations of O, S, N, P, B, Si, Ge, and Se, wherein the heterocyclic alkyl group is preferably C3-C4. 10 Heterocyclic alkyl groups, including cycloamino, morpholino, piperidinyl, pyrrolyl, cyclohexyl ether, thioether, tetrahydrofuran, tetrahydropyran, and tetrahydrothiophene; R, R', S a S b R a R b When R1, R2, R3, R4, and R5 are alkoxy groups, C1-C4 alkoxy groups are preferred, including methoxy, ethoxy, propoxy, butoxy, and tert-butyloxy groups; R, R', and S a S b R a R b When R1, R2, R3, R4, and R5 are silane-based, C3-C is preferred. 18 Silyl groups, including trimethylsilyl, triethylsilyl, tri-tert-butylsilyl, tert-butyldimethylsilyl, tert-butyldiethylsilyl, triphenylsilyl, phenyldimethylsilyl, and diphenylmethylsilyl, with trimethylsilyl and tert-butyldimethylsilyl being more preferred; R, R', S a S b R a R b When R1, R2, R3, R4, and R5 are germanyl groups, they are preferably C3-C6. 18 Silyl groups, including trimethylgermanium, triethylgermanium, tri-tert-butylgermanium, tert-butyldimethylgermanium, tert-butyldiethylgermanium, triphenylgermanium, phenyldimethylgermanium, and diphenylmethylgermanium, with trimethylgermanium and tert-butyldimethylgermanium being more preferred; R, R', S a S b R a R b When R1, R2, R3, R4, and R5 are alkenyl, cycloalkenyl, and heteroalkenyl groups, they refer to groups whose alkyl, cycloalkyl, and heteroalkyl structures contain at least one carbon-carbon double bond, wherein the heteroatom is one or more combinations of O, S, N, P, B, Si, Ge, and Se; R, R', and S a S b R a R b When R1, R2, R3, R4, and R5 are alkynyl groups, they refer to groups whose alkyl structure contains at least one carbon-carbon triple bond; R, R', and S a S b R a R b When R1, R2, R3, R4, and R5 are aryl groups, C6-C is preferred. 24 Aryl groups, including phenyl, naphthyl, anthracene, diphenyl, terphenyl, fluorene, and triphenylene; R, R', R a R b R a R b When R1, R2, R3, R4, and R5 are heteroaryl groups, C4-C is preferred. 30 Heteroaryl groups include furan, thiophene, benzofuran, benzothiophene, dibenzofuran, dibenzothiophene, carbazole, selenophene, benzoselenophene, dibenzoselenophene, pyridine, imidazole, oxazole, thiazole, oxadiazole, dioxazole, pyridazine, pyrimidine, pyrazine, triazine, indole, benzimidazole, benzoxazole, benzothiazole, quinoline, isoquinoline, benzofuran-pyridine, furan-dipyridine, benzothiophene-pyridine, thiophene-dipyridine, azirone, cycloborane; more preferably benzofuran, benzothiophene, dibenzofuran, dibenzothiophene, carbazole, imidazole, pyridine, indole-carbazole, triazine, benzimidazole.

4. The organometallic complex luminescent material according to claim 1, characterized in that, Ring H1 and ring H2 are each independently selected from the following structures: benzene, pyridine, pyrimidine, pyridazine, pyrazine, triazine, imidazole, imidazole-derived carbenes, pyrazole, pyrrole, oxazole, furan, thiophene, thiazole, triazole, naphthalene, quinoline, isoquinoline, quinazoline, benzofuran, aza-benzofuran, benzoxazole, aza-benzoxazole, benzothiophene, aza-benzothiophene, benzothiazole, aza-benzothiazole, benzoselenene, aza-benzoselenene, indene, Aza-indole, indole, aza-indole, benzimidazole, benzimidazole-derived carbenes, aza-benzimidazole, aza-benzimidazole-derived carbenes, naphtho-imidazolium, aza-naphtho-imidazolium, carbazole, aza-carbazole, dibenzofuran, aza-dibenzofuran, phenanthrene[3,2-b]benzofuran, dibenzothiophene, aza-dibenzothiophene, quinoxaline, phthalazine, phenanthrene, aza-phenanthrene, anthracene, aza-anthracene, phenanthridine, fluorene, and aza-fluorene; Formula II is selected from the following structure:

5. The organometallic complex luminescent material according to claim 4, characterized in that, Formula II is selected from the following structure:

6. The organometallic complex luminescent material according to claim 1, characterized in that, First ligand L A Selected from the following structures: Q1 is B; Y1, Y2, P a P b Each of the following is one of B, N, P, O, S, Se, Si, and Ge; P1 to P 19 They are selected independently from C and N respectively; R c R d R e R f R j R h R i The range of substituents defined by r1, r2, r3, and r4 is related to R. a R b The defined range of substituents is consistent; K 3' It is selected from one of the following: single bond, O, S, N, P, B, C, and Si.

7. The organometallic complex luminescent material according to claim 6, characterized in that, First ligand L A Selected from the following structures:

8. The organometallic complex luminescent material according to claim 1, characterized in that, The structural formulas of the organometallic complex luminescent materials include the following: M(L A )1(L B1 )2、M(L A )2(L B2 )1; When the structural formula is M(L) A )1(L B1 At 2, the second ligand L B1 It has the following general formula structure: R m and R n Substituents define the range and L A The R1 and R2 substituents in the ligand have the same range; Specifically, the second ligand L B1 It has the following structure: When the structural formula is M(L) A )2(L B2 At 1, the second ligand L B2 It has the following general formula structure: R o R p R q Substituents define the range and L A The ranges defined by R1 and R2 in the ligands are the same; specifically, the second ligand L... B2 It has the following structure:

9. The organometallic complex luminescent material according to claim 1, characterized in that, The organometallic complex luminescent material has the following structure:

10. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes an anode, a cathode, and an organic functional layer disposed between the anode and the cathode. The organic functional layer includes a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer. The light-emitting layer includes a host material and a dopant material, and the dopant material includes the organometallic complex light-emitting material as described in claim 1.

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