A red-light iridium complex and its applications

Abstract

The present invention discloses an iridium complex, a preparation method thereof, and an organic light-emitting device. The chemical structural formula of the iridium complex is as follows: wherein, ring A is selected from a C 12 -C 30 polycyclic group formed by the fusion of three or more monocyclic groups, provided that ring A contains at least the general formula II: R1-R5 are the same or different, and each independently is H, deuterium, halogen, -CF3, CN, amino group, substituted or unsubstituted C1-C 10 alkoxy group or substituted or unsubstituted C1-C 30 alkyl group. In the alkyl chain of the C1-C 10 alkoxy group and the C1-C 30 alkyl group, the hydrogen can be independently substituted by deuterium, halogen, -CF3 or CN. Among them, the halogen is selected from fluorine, chlorine, bromine or iodine; R x and R y are the same or different, and each independently contains a saturated alicyclic structure. The iridium complex has excellent red light saturation, luminous efficiency and thermal stability, and can improve the stability and service life of the organic light-emitting device.

Description

Technical Field

[0001] The present invention relates to the technical field of organic electroluminescence, and particularly to a fused-ring and cycloalkyl-based iridium complex for red light and its application in organic electroluminescent devices. Background Art

[0002] An organic electroluminescent device (OLEDs) is a device prepared by depositing an organic material between two metal electrodes by spin coating or vacuum evaporation. As early as 1963, Pope et al. published an article on electroluminescence of anthracene single crystals. However, due to the need for a very high driving voltage (>300V), the research on anthracene single crystals was still at the basic research level and could not be used in commercial electronic devices. In 1987, Tang and Van Slyke of Eastman Kodak Company in the United States developed a sandwich-structured organic electroluminescent device, using aluminum tris(8-hydroxyquinoline) (Alq3) as the electron transport layer and the light-emitting layer, and an aromatic diamine as the hole transport layer. The operating voltage of the device was less than 10V, and the brightness exceeded 1000 cd m -2 (Tang, C.W., VanSlyke, S.A. (1989). Organic Electroluminescent Diodes. In: Shionoya, S., Kobayashi, H. (eds) Electroluminescence. Springer Proceedings in Physics, vol 38. Springer, Berlin, Heidelberg.). This breakthrough research triggered a milestone development of OLEDs. Since then, due to the advantages of simple structure, fast response speed, power saving, wide color gamut, high contrast, etc., organic light-emitting devices have been widely used in flat panel displays such as mobile phones and computers.

[0003] A classic three-layer organic electroluminescent device includes a hole transport layer, a light-emitting layer, and an electron transport layer. The holes generated from the anode pass through the hole transport layer and combine with the electrons generated from the cathode passing through the electron transport layer to form excitons in the light-emitting layer, and then emit light. Organic electroluminescent devices can emit various required lights by changing the material of the light-emitting layer as needed.

[0004] Since the injected carriers are half-spin particles, the spin multiplicity of the excited state generated by recombination is determined by spin statistics, that is, 25% of the excitons are singlet excited states, and 75% of the excitons are triplet excited states. The radiative transition paths corresponding to these two types of excitons are fluorescence of singlet states and phosphorescence of triplet states, respectively. The earliest fluorescent OLEDs only rely on 25% singlet excitons, and 75% of the triplet excitons are wasted.

[0005] In 1998, S. Forrest, M. Baldo, etc. first applied metal complexes as luminescent materials in OLEDs, breaking through the limit that the internal quantum efficiency of fluorescent materials is lower than 25%, attempting to achieve 100% internal quantum efficiency to improve the efficiency of the device. Therefore, the research on highly efficient phosphorescent organic light-emitting devices provides an important impetus for the development of the flat panel and portable display industries.

[0006] Iridium has a relatively large atomic number, which can enable the complex to generate strong spin-orbit coupling, facilitating phosphorescence emission; the d-orbital energy levels in iridium metal ions are split relatively large, avoiding interaction with the MLCT state of the complex and reducing the phosphorescence emission efficiency; trivalent iridium ions can form very stable neutral molecules with ligands, facilitating the preparation of devices by vacuum evaporation or solution processing. In addition, the emission light color of the complex can cover the entire visible spectrum and has good stability, etc., meeting the requirements of electroluminescent luminescent materials, making iridium complexes the focus of research on organic electroluminescent phosphorescent materials.

[0007] However, due to the relatively narrow energy gap of red iridium complexes, it is difficult to match the energy levels between the red light material and the charge transport layer, and concentration quenching is likely to occur, resulting in unsatisfactory comprehensive performance of red light devices and affecting the color saturation of the entire device. Therefore, the research on red iridium complexes and devices is particularly important for device performance (such as in terms of efficiency, voltage, lifespan, etc.). Iridium complex auxiliary ligands can be used to finely tune the emission wavelength, improve sublimation properties, thermal stability, and increase the efficiency of the material. Existing acetylacetone ligands, especially those with branched alkyl side chains, have achieved some effects in the above properties, but there are still certain deficiencies in terms of luminescence efficiency and lifespan.

[0008] Therefore, there is a need in this field to further improve the color saturation, luminescence efficiency, and device lifespan of the device. Summary of the Invention

[0009] The object of the present invention is to provide an iridium complex, which can further enhance the color saturation (red saturation), luminescence efficiency, and device lifespan of the device by adjusting the structural combination of the main ligand and the auxiliary ligand.

[0010] Another object of the present invention is to provide a synthesis method for synthesizing the above iridium complex.

[0011] Another object of the present invention is to provide a device using the above iridium complex as a red light doping material.

[0012] Technical Solution:

[0013] To achieve the above invention objects, the present invention provides an iridium complex represented by General Formula I:

[0014]

[0015] Among them,

[0016] ring A is selected from C of three or more single-ring groups fused to each other 12 -C 30 polycyclic group, provided that: the C represented by ring A 12 -C 30 The polycyclic group contains at least the structure of general formula II:

[0017]

[0018] Among them, * represents the binding site of general formula II to Ir(I), and *' represents the binding site of general formula II to the benzene ring in general formula I;

[0019] a is selected from integers from 0 to 20. When a represents an integer ≥ 2, R1 can be the same or different from each other, and the positions of R1 can be the same or different;

[0020] R1, R2, R3, R4 and R5 are the same or different, and are each independently H, deuterium, halogen, -CF3, CN, amino, substituted or unsubstituted C1-C 10 alkoxy or substituted or unsubstituted C1-C 30 alkyl, the hydrogen in the alkyl chain of C1-C 10 alkoxy and C1-C 30 alkyl can each independently be substituted by deuterium, halogen, -CF3 or CN, where halogen is selected from fluorine, chlorine, bromine or iodine; and

[0021] R x and R y are the same or different and each independently contain a saturated alicyclic structure.

[0022] In some embodiments of the present invention, ring A is a group in which general formula II is fused with 1-3 five-membered or six-membered rings.

[0023] In some embodiments of the present invention, ring A is a group in which general formula II is fused with 1-3 aromatic rings.

[0024] Specifically, the more aromatic ring structures fused with the general formula II structure of the present invention, the higher the energy difference between the ground state and the excited state, which further improves the luminescence efficiency and can also enhance the color saturation of the red light of the device. However, the number of fused rings should not be too many. When the number of fused rings exceeds 3, the stability of the compound will decrease, resulting in a reduction in the device lifetime and possibly causing the emission wavelength of the device to exceed the visible light range and emit infrared light.

[0025] In some embodiments of the present invention, the aromatic ring is a benzene ring.

[0026] In some embodiments of the present invention, ring A is a group fused with one aromatic ring of general formula II.

[0027] In some embodiments of the present invention, ring A is fused with one benzene ring of general formula II.

[0028] In some embodiments of the present invention, the structure of ring A is selected from any one of general formulas RD-1 to RD-3:

[0029]

[0030] Specifically, fusing a benzene ring on the basis of general formula II helps to improve the color saturation of the device and at the same time provides high luminous efficiency; and the structure has better thermal stability, which helps to improve the device life.

[0031] In some embodiments of the present invention, in any of the structures of RD-1 to RD-3, a represents any integer from 0 to 8, specifically it can be 0, 1, 2, 3, 4, 5, 6, 7 or 8; when a represents an integer ≥2, R1 can be the same or different and are each independently selected from H, deuterium, halogen, -CF3, CN, amino, substituted or unsubstituted C1-C 10 alkoxy or substituted or unsubstituted C1-C 30 alkyl.

[0032] In some embodiments of the present invention, the hydrogen in the alkyl can be independently substituted by deuterium, halogen, -CF3 or CN.

[0033] In some embodiments of the present invention, the halogen includes fluorine, chlorine, bromine or iodine.

[0034] In some embodiments of the present invention, the alkyl includes straight-chain alkyl or branched-chain alkyl.

[0035] In some preferred embodiments of the present invention, when a represents an integer ≥2, R1 can be the same or different and are each independently selected from H, deuterium, halogen, -CF3, CN or amino.

[0036] In some preferred embodiments of the present invention, when a represents an integer ≥2, R1 can be the same or different and are each independently selected from substituted or unsubstituted C1-C 10 alkoxy.

[0037] In some preferred embodiments of the present invention, when a represents an integer ≥2, R1 can be the same or different and are each independently selected from substituted or unsubstituted C1-C4 alkoxy.

[0038] In some preferred embodiments of the present invention, the alkoxy group is selected from methoxy, ethoxy, or propoxy.

[0039] In some preferred embodiments of the present invention, when a represents an integer ≥ 2, R1 may be the same or different and each independently selected from substituted or unsubstituted C1-C 20 alkyl.

[0040] In some preferred embodiments of the present invention, when a represents an integer ≥ 2, R1 may be the same or different and each independently selected from substituted or unsubstituted C1-C 10 alkyl.

[0041] In some preferred embodiments of the present invention, when a represents an integer ≥ 2, R1 may be the same or different and each is independently selected from a substituted or unsubstituted C1-C4 alkyl group.

[0042] In some preferred embodiments of the present invention, the alkyl group is selected from methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, neopentyl, 1-methylpentyl, 2-methylpentyl, 1-pentylhexyl, 1-butylpentyl, 1-heptyloctyl or 3-methylpentyl.

[0043] In some preferred embodiments of the present invention, the alkyl group is selected from the group consisting of methyl, ethyl, propyl, isopropyl, butyl, and isobutyl.

[0044] In some embodiments of the present invention, the general formula RD-1 contains 8 substitutable positions (i.e., a can be any integer from 0 to 8), and the substituents on the 8 substitutable positions are labeled T. 11 、T 12 、T 13 、T 14 、T 15 、T 16 、T 17 and T 18 :

[0045]

[0046] In some preferred embodiments of the present invention, T in the general formula RD-1 11 -T 18 At least one of them is not hydrogen, and at most three of them are not hydrogen.

[0047] In some preferred embodiments of the present invention, T in the general formula RD-1 11 -T 18 One of them is not hydrogen.

[0048] In some preferred embodiments of the present invention, in the general formula RD-1, any one of T 14 , T 15 , T 17 and T 18 is not hydrogen. Substitution at the corresponding positions of T 14 , T 15 , T 17 , T 18 in the general formula RD-1 can enable the prepared iridium complex to provide higher luminous efficiency and stability for the device.

[0049] In some preferred embodiments of the present invention, any substituent in T 11 -T 18 that is not hydrogen is selected from deuterium, halogen, -CF3, CN, amino group, substituted or unsubstituted C1-C 10 alkoxy group or substituted or unsubstituted C1-C4 alkyl group. The hydrogen in the alkyl chain of the C1-C 10 alkoxy group and the C1-C4 alkyl group can be independently substituted by deuterium, halogen, -CF3 or CN respectively.

[0050] In some preferred embodiments of the present invention, any substituent in T 11 -T 18 that is not hydrogen is selected from deuterium, fluorine, -CF3, amino group, CN or C1-C4 alkyl group.

[0051] In some preferred embodiments of the present invention, any substituent in T 13 -T 16 that is not hydrogen is selected from deuterium, fluorine, -CF3, amino group, CN or C1-C4 alkyl group.

[0052] In some preferred embodiments of the present invention, the C1-C4 alkyl group is selected from any one of methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl and tert-butyl.

[0053] In some preferred embodiments of the present invention, any two of T 11 -T 18 in the general formula RD-1 are not hydrogen.

[0054] In some preferred embodiments of the present invention, any two of T 13 -T 16 in the general formula RD-1 are not hydrogen.

[0055] In some preferred embodiments of the present invention, the two substituents that are not hydrogen in the general formula RD-1 include T 14 and / or T 16 .

[0056] In some preferred embodiments of the present invention, in the general formula RD-1, T 13 , T 14 , T 16 Any two of them are not hydrogen.

[0057] In some preferred embodiments of the present invention, in the general formula RD-1, T 11 -T 18 Any two substituents that are not hydrogen are each independently selected from deuterium, halogen, -CF3, amino, CN, or substituted or unsubstituted C1-C4 alkyl, and the hydrogen in the alkyl chain of the C1-C4 alkyl can be independently substituted by deuterium, halogen, -CF3, or CN.

[0058] In some preferred embodiments of the present invention, the C1-C4 alkyl is selected from methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, or tert-butyl.

[0059] In some preferred embodiments of the present invention, in the general formula RD-1, T 11 -T 18 At least one of them is selected from F, amino, or -CF3.

[0060] In some preferred embodiments of the present invention, in the general formula RD-1, T 13 , T 14 , T 16 At least one of them is selected from F, amino, or -CF3.

[0061] Specifically, when the substituent includes F or -CF3, the luminous efficiency of the device can be further improved.

[0062] In some preferred embodiments of the present invention, in the general formula RD-1, T 11 -T 18 Any three of them are not hydrogen.

[0063] In some preferred embodiments of the present invention, in the general formula RD-1, T 13 -T 18 Any three of them are not hydrogen.

[0064] In some preferred embodiments of the present invention, in the general formula RD-1, T 11 -T 18 Any three substituents that are not hydrogen are each independently selected from deuterium, halogen, -CF3, amino, CN, or substituted or unsubstituted C1-C4 alkyl, and the hydrogen in the alkyl chain of the C1-C4 alkyl can be independently substituted by deuterium, halogen, -CF3, or CN.

[0065] In some preferred embodiments of the present invention, in the general formula RD-1, T 11 -T18 At least one is selected from F, amino group or -CF3.

[0066] In some preferred embodiments of the present invention, in the general formula RD-1, T 11 -T 18 At least one is selected from F or -CF3.

[0067] In some preferred embodiments of the present invention, in the general formula RD-1, T 13 -T 18 At least one is selected from F, amino group or -CF3.

[0068] In some preferred embodiments of the present invention, in the general formula RD-1, T 13 -T 16 At least one is selected from F, amino group or -CF3.

[0069] In some preferred embodiments of the present invention, in the general formula RD-1, T 13 -T 18 At least one is selected from F or -CF3.

[0070] In some preferred embodiments of the present invention, when the number of substituents other than hydrogen in T 11 -T 18 in the general formula RD-1 ≥ 2, any two or more of the substituent groups can be connected to each other to form a carbocyclic group.

[0071] In some preferred embodiments of the present invention, the carbocyclic group can be a C5-C 20 carbocyclic group.

[0072] Wherein, the hydrogen on the C5-C 20 carbocyclic group can be independently substituted by a substituent selected from deuterium, halogen, -CF3, CN or a substituted or unsubstituted C1-C4 alkyl group.

[0073] In some embodiments of the present invention, the general formula RD-2 contains 8 substitutable positions (i.e., a can be any integer from 0 to 8), and the substituents at the 8 substitutable positions are labeled as T 21 , T 22 , T 23 , T 24 , T 25 , T 26 , T 27 and T 28 :

[0074]

[0075] In some preferred embodiments of the present invention, in the general formula RD-2, T 21 -T28 At least one of them is not hydrogen, and at most three of them are not hydrogen.

[0076] In some preferred embodiments of the present invention, in the general formula RD-2, T 21 -T 28 One of them is not hydrogen.

[0077] In some preferred embodiments of the present invention, in the general formula RD-2, T 23 or T 28 Any one of them is not hydrogen. In the general formula RD-2, T 23 or T 28 Substitution at the corresponding position can make the prepared iridium compound provide higher luminescence efficiency and stability for the device.

[0078] In some preferred embodiments of the present invention, any substituent in T 21 -T 28 that is not hydrogen is selected from deuterium, halogen, -CF3, CN, amino group, substituted or unsubstituted C1-C 10 alkoxy group or substituted or unsubstituted C1-C4 alkyl group. The hydrogen in the alkyl chain of the C1-C 10 alkoxy group or C1-C4 alkyl group can be independently substituted by deuterium, halogen, -CF3 or CN.

[0079] In some preferred embodiments of the present invention, any substituent in T 21 -T 28 that is not hydrogen is selected from deuterium, fluorine, -CF3, CN, C1-C4 alkyl group or C1-C4 alkoxy group.

[0080] In some preferred embodiments of the present invention, the C1-C4 alkyl group is selected from any one of methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl or tert-butyl.

[0081] In some preferred embodiments of the present invention, in the general formula RD-2, T 21 -T 28 Any two of them are not hydrogen.

[0082] In some preferred embodiments of the present invention, in the general formula RD-2, T 23 -T 28 Any two of them are not hydrogen.

[0083] In some preferred embodiments of the present invention, the two substituents in the general formula RD-2 that are not hydrogen include T 23 and / or T 28 .

[0084] In some preferred embodiments of the present invention, in the general formula RD-2, T 21 -T28 Any two substituents other than hydrogen are each independently selected from deuterium, halogen, -CF3, CN, or substituted or unsubstituted C1-C4 alkyl or alkoxy, and the hydrogen in the alkyl chain of the C1-C4 alkyl can be independently substituted by deuterium, halogen, -CF3, or CN.

[0085] In some preferred embodiments of the present invention, the C1-C4 alkyl is selected from methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, or tert-butyl.

[0086] In some preferred embodiments of the present invention, in the general formula RD-2, T 21 -T 28 at least one is selected from F, C1-C4 alkoxy, or -CF3.

[0087] In some preferred embodiments of the present invention, in the general formula RD-2, T 21 -T 28 at least one is selected from F or -CF3.

[0088] In some preferred embodiments of the present invention, in the general formula RD-2, T 23 -T 28 at least one is selected from F, C1-C4 alkoxy, or -CF3, thereby further improving the light emission efficiency of the device.

[0089] In some preferred embodiments of the present invention, in the general formula RD-2, T 23 -T 28 at least one is selected from F or -CF3, thereby further improving the light emission efficiency of the device.

[0090] In some preferred embodiments of the present invention, in the general formula RD-2, T 21 -T 28 any three are not hydrogen.

[0091] In some preferred embodiments of the present invention, in the general formula RD-2, T 23 -T 28 any three are not hydrogen.

[0092] In some preferred embodiments of the present invention, in the general formula RD-2, T 21 -T 28 any three substituents that are not hydrogen are each independently selected from deuterium, halogen, -CF3, CN, or substituted or unsubstituted C1-C4 alkyl, and the hydrogen in the alkyl chain of the C1-C4 alkyl can be independently substituted by deuterium, halogen, -CF3, or CN.

[0093] In some preferred embodiments of the present invention, in the general formula RD-2, T 21 -T28 At least one is selected from F, -OCH3 or -CF3.

[0094] In some preferred embodiments of the present invention, in the general formula RD-2, T 21 -T 28 At least one is selected from F or -CF3.

[0095] In some preferred embodiments of the present invention, in the general formula RD-2, T 23 -T 28 At least one is selected from F, -OCH3 or -CF3.

[0096] In some preferred embodiments of the present invention, in the general formula RD-2, T 23 -T 28 At least one is selected from F or -CF3.

[0097] In some preferred embodiments of the present invention, when the number of substituents other than hydrogen in T 21 -T 28 in the general formula RD-2 ≥ 2, any two or more of the substituent groups may be connected to each other to form a carbocyclic group.

[0098] In some preferred embodiments of the present invention, the carbocyclic group may be a C5-C 20 carbocyclic group.

[0099] Among them, the hydrogen on the C5-C 20 carbocyclic group may be independently substituted by a substituent selected from deuterium, halogen, -CF3, CN or a substituted or unsubstituted C1-C4 alkyl group.

[0100] In some embodiments of the present invention, the general formula RD-3 contains 8 substitutable positions (i.e., a can be any integer from 0 to 8), and the substituents at the 8 substitutable positions are labeled as T 31 、T 32 、T 33 、T 34 、T 35 、T 36 、T 37 and T 38 :

[0101]

[0102] In some preferred embodiments of the present invention, in the general formula RD-3, at least one of T 31 -T 38 is not hydrogen, and at most three are not hydrogen.

[0103] In some preferred embodiments of the present invention, in the general formula RD-3, T 31-T 38 One of them is not hydrogen.

[0104] In some preferred embodiments of the present invention, in the general formula RD-3, T 33 -T 38 Any one of them is not hydrogen. In the general formula RD-2, T 33 -T 38 Substituting at the corresponding position can make the prepared iridium complex provide higher luminescence efficiency and stability for the device.

[0105] In some preferred embodiments of the present invention, T 31 -T 38 Any substituent that is not hydrogen is selected from deuterium, halogen, -CF3, CN, amino group, substituted or unsubstituted C1-C 10 alkoxy or substituted or unsubstituted C1-C4 alkyl, and the hydrogen in the alkyl chain of C1-C 10 alkoxy and C1-C4 alkyl can be independently substituted by deuterium, halogen, -CF3 or CN.

[0106] In some preferred embodiments of the present invention, T 21 -T 28 Any substituent that is not hydrogen is selected from deuterium, fluorine, -CF3, CN, C1-C4 alkyl or C1-C4 alkoxy.

[0107] In some preferred embodiments of the present invention, C1-C4 alkyl is selected from any one of methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl or tert-butyl.

[0108] In some preferred embodiments of the present invention, in the general formula RD-3, T 31 -T 38 Any two of them are not hydrogen.

[0109] In some preferred embodiments of the present invention, in the general formula RD-3, T 34 -T 37 Any two of them are not hydrogen.

[0110] In some preferred embodiments of the present invention, in the general formula RD-3, T 35 、T 37 and T 38 Any two of them are not hydrogen.

[0111] In some preferred embodiments of the present invention, the two substituents that are not hydrogen in the general formula RD-3 include T 35 and / or T 37 .

[0112] In some preferred embodiments of the present invention, in the general formula RD-3, T31 -T 38 Any two substituents other than hydrogen in it are each independently selected from deuterium, halogen, -CF3, CN, or substituted or unsubstituted C1-C4 alkyl or alkoxy groups, and the hydrogen in the alkyl chain of the C1-C4 alkyl group can each independently be substituted by deuterium, halogen, -CF3, or CN.

[0113] In some preferred embodiments of the present invention, the C1-C4 alkyl group is selected from methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, or tert-butyl.

[0114] In some preferred embodiments of the present invention, T in the general formula RD-3 31 -T 38 At least one of them is selected from F, C1-C4 alkyl or alkoxy group, or -CF3.

[0115] In some preferred embodiments of the present invention, T in the general formula RD-3 35 、T 37 or T 38 At least one of them is selected from F, C1-C4 alkyl or alkoxy group, or -CF3, thereby further improving the light-emitting efficiency of the device.

[0116] In some preferred embodiments of the present invention, T in the general formula RD-3 31 -T 38 Any three of them are not hydrogen.

[0117] In some preferred embodiments of the present invention, T in the general formula RD-3 32 、T 34 and T 35 -T 38 Any three of them are not hydrogen.

[0118] In some preferred embodiments of the present invention, T in the general formula RD-3 31 -T 38 Any three substituents other than hydrogen in it are each independently selected from deuterium, halogen, -CF3, CN, or substituted or unsubstituted C1-C4 alkyl or alkoxy groups, and the hydrogen in the alkyl chain of the C1-C4 alkyl group can each independently be substituted by deuterium, halogen, -CF3, C1-C4 alkyl or alkoxy group, or CN.

[0119] In some preferred embodiments of the present invention, T in the general formula RD-3 31 -T 38 At least one of them is selected from F, C1-C4 alkyl or alkoxy group, or -CF3.

[0120] In some preferred embodiments of the present invention, T in the general formula RD-3 34 -T 37At least one of them is selected from F, C1-C4 alkyl or alkoxy, or -CF3.

[0121] In some preferred embodiments of the present invention, in the general formula RD-3, T 32 , T 34 and T 35 -T 38 At least one of them is selected from F, C1-C4 alkyl or alkoxy, or -CF3.

[0122] In some preferred embodiments of the present invention, when the number of substituents other than hydrogen in T 31 -T 38 in the general formula RD-3 is ≥2, any two or more of the substituent groups can be connected to each other to form a carbocyclic group.

[0123] In some preferred embodiments of the present invention, the carbocyclic group can be a C5-C 20 carbocyclic group.

[0124] Among them, the hydrogen on the C5-C 20 carbocyclic group can be independently substituted by a substituent selected from deuterium, halogen, -CF3, CN, or substituted or unsubstituted C1-C4 alkyl.

[0125] In some embodiments of the present invention, ring A is a group formed by fusing the general formula II with 2 aromatic rings.

[0126] In some embodiments of the present invention, the structure formed by fusing the general formula II with 2 benzene rings is selected from any one of RD-4 to RD-12:

[0127] In some embodiments of the present invention, ring A can be a group formed by fusing the general formula II with 3 aromatic rings.

[0128] In some embodiments of the present invention, the structure formed by fusing the general formula II with 3 benzene rings is preferably RD-13:

[0129]

[0130] In some embodiments of the present invention, ring A can be a group formed by fusing the general formula II with a saturated or unsaturated five-membered ring.

[0131] In some embodiments of the present invention, the group formed by fusing the general formula II with a saturated or unsaturated five-membered ring can be any one of RD-14 to RD-18.

[0132]

[0133]

[0134] In some embodiments of the present invention, Ring A can be a group in which Formula II is fused with a five- or six-membered heterocyclic ring containing N, O, or S.

[0135] In some embodiments of the present invention, the group in which Formula II is fused with a five- or six-membered heterocyclic ring containing N, O, or S can be any one of RD-19 to RD-27:

[0136]

[0137] In some embodiments of the present invention, Ring A can be a group in which Formula II is fused with a benzene ring through a five-membered ring, and the carbon atoms in the five-membered ring that are not involved in the fusion can be substituted by N, O, or S.

[0138] In some embodiments of the present invention, the group in which Formula II is fused with a benzene ring through a five-membered ring can be any one of RD-28 to RD-42:

[0139]

[0140] In some embodiments of the present invention, the substituents at the substitutable positions in Formulas RD-4 to RD-42 are labeled as P n , where n is an integer greater than 0, and the number of substituents that can be contained at the same substitutable position is denoted as m, m = 0, 1, or 2; Ring A can be any one of the following formulas:

[0141]

[0142]

[0143]

[0144]

[0145]

[0146]

[0147] where P1-P 124 are each independently selected from the group consisting of H, deuterium, halogen, -CF3, CN, amino, substituted or unsubstituted C1-C 10 alkoxy, or substituted or unsubstituted C1-C 30 alkyl, and the hydrogen atoms in the alkyl chains of C1-C 10 alkoxy and C1-C 30 alkyl can each independently be substituted by deuterium, halogen, -CF3, or CN, where the halogen is selected from fluorine, chlorine, bromine, or iodine.

[0148] In some embodiments of the present invention, when m is 2, P 49 , P 53 , P 54 and P 88 -P 92 may be the same or different.

[0149] In some embodiments of the present invention, P1-P 124 are each independently deuterium, a halogen, -CF3, CN, or a C1-C 10 alkyl group which is substituted or unsubstituted by deuterium, a halogen, -CF3, or CN; m is an integer from 0 to 2; the halogen includes fluorine, chlorine, bromine, or iodine.

[0150] In some preferred embodiments of the present invention, P1-P 124 are each independently selected from substituted or unsubstituted C1-C 20 alkyl groups.

[0151] In some preferred embodiments of the present invention, P1-P 124 are each independently selected from substituted or unsubstituted C1-C 10 alkyl groups.

[0152] In some preferred embodiments of the present invention, P1-P 124 are each independently selected from substituted or unsubstituted C1-C4 alkyl groups.

[0153] In some preferred embodiments of the present invention, the alkyl group is selected from methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, neopentyl, 1-methylpentyl, 2-methylpentyl, 1-pentylhexyl, 1-butylpentyl, 1-heptyloctyl, or 3-methylpentyl.

[0154] In some preferred embodiments of the present invention, the alkyl group is selected from methyl, ethyl, propyl, isopropyl, butyl, or isobutyl.

[0155] In some embodiments of the present invention, in general formula I, R2, R3, R4, and R5 are the same or different and are each independently selected from H or C1-C 10 alkyl groups.

[0156] In some preferred embodiments of the present invention, in general formula I, R2, R3, R4, and R5 are the same or different and are each independently selected from H or C1-C4 alkyl groups.

[0157] Specifically, C1-C10 The alkyl group is selected from methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl or n-decyl. The C1-C4 alkyl group is selected from methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl or tert-butyl.

[0158] In some preferred embodiments of the present invention, one or more of R2, R3, R4 and R5 are not hydrogen.

[0159] In some preferred embodiments of the present invention, any one of R2, R3, R4 and R5 is not hydrogen.

[0160] In some preferred embodiments of the present invention, any two of R2, R3, R4 and R5 are not hydrogen.

[0161] In some preferred embodiments of the present invention, R2 and R3 are not hydrogen.

[0162] In some preferred embodiments of the present invention, R3 and R4 are not hydrogen.

[0163] In some preferred embodiments of the present invention, R4 and R5 are not hydrogen.

[0164] In some preferred embodiments of the present invention, R3 and R5 are not hydrogen.

[0165] In some preferred embodiments of the present invention, any three of R2, R3, R4 and R5 are not hydrogen.

[0166] In some preferred embodiments of the present invention, R2, R3 and R4 are not hydrogen.

[0167] In some preferred embodiments of the present invention, R2, R3 and R5 are not hydrogen.

[0168] In some preferred embodiments of the present invention, R3, R4 and R5 are not hydrogen.

[0169] In some embodiments of the present invention, in the auxiliary ligand moiety of Formula I, R x and R y may be the same or different and each independently contains a saturated alicyclic structure. The saturated alicyclic structure has relatively high thermal stability, thereby improving the thermal stability of the iridium complex of Formula I.

[0170] In some preferred embodiments of the present invention, R x and R y each independently contains a saturated C3-C8 monocyclic ring.

[0171] In some preferred embodiments of the present invention, R xand R y each independently includes a saturated C3-C8 monocyclic structure selected from any one of the following ring structures:

[0172]

[0173] In some preferred embodiments of the present invention, R x and R y each independently includes a saturated C5-C6 monocyclic ring.

[0174] Specifically, specific examples of the C5-C6 monocyclic ring are as follows: When the number of carbon atoms in the monocyclic ring is 5-6, the ring strain is small, so that the thermal stability of the iridium complex of general formula I can be further improved, and the service life of the device can be further improved.

[0175] In some preferred embodiments of the present invention, R x and R y each independently includes a C7-C 15 spiro ring or bridged ring.

[0176] In some preferred embodiments of the present invention, R x and R y each independently includes a saturated C7-C 15 spiro ring or bridged ring structure selected from any one of the following ring structures:

[0177]

[0178] Specifically, the above C7-C 15 spiro ring or bridged ring structure has appropriate ring strain, so that the thermal stability of the iridium complex of general formula I can be further improved, and the service life of the device can be further improved.

[0179] In some preferred embodiments of the present invention, R x and R y each independently is a ring structure formed by connecting two or more saturated alicyclic rings (for example, saturated C3-C8 monocyclic rings, saturated C7-C 15 spiro rings and saturated C7-C 15 bridged rings) through single bonds.

[0180] In some preferred embodiments of the present invention, R x and R y can each independently be a ring structure formed by connecting two or more C3-C8 monocyclic rings through single bonds.

[0181] In some preferred embodiments of the present invention, R x and R yEach may independently be two or more C7-C 15 a ring structure formed by connecting spiro rings through single bonds.

[0182] In some preferred embodiments of the present invention, R x and R y Each may independently be two or more C7-C 15 a ring structure formed by connecting bridged rings through single bonds.

[0183] In some preferred embodiments of the present invention, R x and R y Each may independently be one or more C7-C 15 a ring structure formed by connecting one or more spiro rings and one or more C3-C8 monocyclic rings through single bonds.

[0184] In some preferred embodiments of the present invention, R x and R y Each may independently be one or more C7-C 15 a ring structure formed by connecting one or more bridged rings and one or more C3-C8 monocyclic rings through single bonds.

[0185] In some preferred embodiments of the present invention, one or more hydrogens in the ring structures independently included in R x and R y may each independently be substituted by a substituent selected from deuterium, halogen, -CF3, -CN or C1-C4 alkyl. The substitution may be monosubstitution or polysubstitution, and one hydrogen or two hydrogens on the same carbon atom may be substituted. The number of substitutions does not exceed the number of substitutable positions of the ring where it is located, and the substituents may be the same or different. Each substituent is independently selected from deuterium, halogen, -CF3, -CN or C1-C4 alkyl.

[0186] Specifically, the halogen is selected from fluorine, chlorine, bromine or iodine; the C1-C4 alkyl is selected from methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl or tert-butyl.

[0187] In some preferred embodiments of the present invention, the auxiliary ligand structure in Formula I is selected from any one of RP-1 to RP-21:

[0188]

[0189] In some preferred embodiments of the present invention, the main ligand of Formula I includes any one of Formulae RD-1 to RD-42.

[0190] In some preferred embodiments of the present invention, the main ligand of Formula I includes any one of Formulae RD-1 to RD-18.

[0191] In some preferred embodiments of the present invention, the main ligand of general formula I comprises any one of general formulas RD-1 to RD-13.

[0192] In some preferred embodiments of the present invention, the main ligand of general formula I comprises any one of general formulas RD-1 to RD-3.

[0193] In a further preferred embodiment of the present invention, the main ligand of general formula I is selected from any one of the following:

[0194]

[0195]

[0196] In some preferred embodiments of the present invention, the auxiliary ligand of general formula I is selected from any one of RP-1 to RP-21.

[0197] In some preferred embodiments of the present invention, the auxiliary ligand of general formula I is selected from any one of RP-9 to RP-21.

[0198] In some preferred embodiments of the present invention, the auxiliary ligand of general formula I is selected from any one of RP-9, RP-12, and RP-13 to RP-19.

[0199] In a further preferred embodiment of the present invention, the auxiliary ligand of general formula I is selected from any one of RP-13 to RP-19.

[0200] In a further preferred embodiment of the present invention, the auxiliary ligand of general formula I is selected from any one of RP-13 and RP-19.

[0201] In some preferred embodiments of the present invention, the combination of the main ligand and the auxiliary ligand of general formula I is selected from any one of the following: RD-1 and RP-13, RD-2 and RP-13, RD-3 and RP-13, RD-1 and RP-14, RD-2 and RP-14, RD-3 and RP-14, RD-1 and RP-16, RD-2 and RP-16, RD-3 and RP-16, RD-1 and RP-17, RD-2 and RP-17, RD-3 and RP-17, RD-1 and RP-18, RD-2 and RP-18, RD-3 and RP-18, RD-1 and RP-19, RD-2 and RP-19, or RD-3 and RP-19.

[0202] In some preferred embodiments of the present invention, general formula I is selected from any one of the structures represented by RDP-1 to RDP-52.

[0203]

[0204]

[0205]

[0206]

[0207]

[0208] When the compound of general formula I in the present invention contains the structure of general formula RD-1, the compound of general formula I is preferably the compounds represented by RDP-1 to RDP-24 and RDP-52; when the compound of general formula I in the present invention contains the structure of general formula RD-2, the compound of general formula I is preferably the compounds represented by RDP-50 and RDP-51; when the compound of general formula I in the present invention contains the structure of RD-3, the compound of general formula I is preferably the compounds represented by RDP-25 to RDP-49; when the above compounds are used as the red light doping material of the organic light emitting device, it can have higher luminous efficiency, better thermal stability at the same time, and can further improve the life of the organic light emitting display device.

[0209] The present invention also provides a method for preparing the iridium complex of general formula I, which specifically comprises the following steps:

[0210] (1) Reacting a precursor substance with trivalent iridium to prepare a dimer;

[0211] (2) Stirring and reacting the dimer with an auxiliary ligand molecule and potassium carbonate or sodium carbonate in a solvent to obtain the compound of general formula I;

[0212] Wherein the structural formula of the precursor substance is as follows:

[0213]

[0214] Wherein the structural formula of the dimer is as follows:

[0215]

[0216] Wherein the structural formula of the auxiliary ligand molecule is as follows:

[0217]

[0218] The present invention also provides an organic electroluminescent device containing the iridium complex of general formula I. The organic electroluminescent device includes an anode, a cathode and an organic layer; the organic layer at least includes a light emitting layer, and the light emitting layer contains any one of the iridium complexes of general formula I in the present invention. The iridium complex of general formula I is added to the light emitting layer material as a red light doping material.

[0219] In some embodiments of the present invention, the organic electroluminescent device emits visible red light.

[0220] In some embodiments of the present invention, the organic layer further includes at least one of a hole injection layer, a hole transport layer, a hole blocking layer, an electron injection layer, or an electron transport layer.

[0221] In some embodiments of the present invention, the organic layer is prepared by any one of vacuum evaporation, molecular beam evaporation, dip coating in a solvent, spin coating, bar coating, or inkjet printing.

[0222] In some embodiments of the present invention, the anode and the cathode are prepared by evaporation or sputtering.

[0223] In some embodiments of the present invention, the organic electroluminescent device can be used to prepare a display or a light-emitting illumination source.

[0224] Advantageous effects: The iridium complex having the structure shown in General Formula I provided by the present invention contains a relatively large number of conjugated structures in the ring A structure, which can improve the color saturation and the light-emitting efficiency of the device. The auxiliary ligand is further combined with the structure of a saturated aliphatic ring, which can further improve the thermal stability of the iridium complex, thereby improving the stability of the device and further improving the service life of the device. Detailed implementation manners

[0225] The technical features of the following-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0226] The following-described embodiments only represent several implementation manners of the present invention, which are convenient for understanding the technical solutions of the present invention specifically and in detail, but should not be construed as limiting the protection scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can be made, and these all belong to the protection scope of the present invention. It should be understood that the technical solutions obtained by those skilled in the art through logical analysis, reasoning, or limited experiments based on the technical solutions provided by the present invention are all within the protection scope of the appended claims of the present invention.

[0227] Preparation of the Complex

[0228] 1. Compound 1: RDP-1

[0229] Step 1: Synthesis of the auxiliary ligand RP-13

[0230] Take a single-necked flask, add DMF (650 mL), then add potassium tert-butoxide (222.29 g) portionwise with stirring, heat to 60 °C, then add IP-1 (100.00 g) dropwise under nitrogen protection. After the addition is complete, continue stirring for 20 min, then add IP-2 (169.02 g) dropwise. After the addition of IP-2 is complete, continue stirring at 60 °C for 30 min and stop heating. Add water and n-hexane for extraction and washing multiple times, collect the organic phase, rotary evaporate the organic phase to remove the solvent, and separate by column chromatography to obtain 169.38 g of a white solid with a yield of 90.44%.

[0231]

[0232] Step 2: Synthesis of intermediate IP-3

[0233] Add 2-chloro-4-iodopyridine-3-carbaldehyde (13.00 g), 2-fluorobenzeneboronic acid (7.48 g) and sodium bicarbonate (8.17 g) to a flask, add toluene (100 mL), ethanol (50 mL) and water (50 mL), replace the air with nitrogen, then add tetrakis(triphenylphosphine)palladium(0) (50 mg), and then heat under reflux with stirring for 4 h. After the reaction is completed, add water and ethyl acetate for extraction, collect the organic phase, and separate by column chromatography to obtain 10.92 g of a white solid with a yield of 95.34%.

[0234] Step 3: Synthesis of intermediate IP-4

[0235] Take a flask, add methoxymethyl(triphenyl)phosphonium chloride (17.46 g) and toluene (150 mL) to it, add potassium tert-butoxide (6.67 g) portionwise under an ice-water bath. After the addition is complete, continue stirring under the ice-water bath for 1 h, then add intermediate IP-3 (10.00 g) dissolved in 50 mL of toluene dropwise. After the addition is complete, remove the ice-water bath and continue stirring for 2 h. After the reaction is completed, quench the reaction with water, then use water and ethyl acetate for extraction and washing multiple times, collect the organic phase, and separate by column chromatography to obtain 8.41 g of a white solid with a yield of 75.15%.

[0236] Step 4: Synthesis of intermediate IP-5

[0237] Take a flask, add intermediate IP-4 (8.00 g) and dichloromethane (80 mL) to it, replace the air with nitrogen, then add methanesulfonic acid (23.32 g) dropwise with stirring. After the addition is complete, continue stirring at room temperature for 2 h. After the reaction is completed, quench with water. Use dichloromethane and water for extraction, collect the organic phase, and separate by column chromatography to obtain 6.30 g of a white solid with a yield of 89.64%.

[0238] Step 5: Synthesis of ligand RD-1-1

[0239] Take a flask, add intermediate IP-5 (6.00 g) and 3,5-dimethylphenylboronic acid (4.66 g) thereto, add toluene (50 mL), ethanol (25 mL) and water (25 mL), displace with nitrogen and stir, then add X-PHOS (200 mg) and palladium acetate (50 mg), heat under reflux for 2 h, detect the end of the reaction, and stop heating. Add water and ethyl acetate for extraction, collect the organic phase, separate by column chromatography, and then recrystallize with ethanol to obtain 6.91 g of white solid, with a yield of 88.53%.

[0240]

[0241] Step 6: Synthesis of complex RDP-1

[0242] Take a flask, add ligand RD-1-1 (2.05 g) and iridium(III) chloride trihydrate (1.00 g) thereto, add 30 mL of ethylene glycol monoethyl ether and 10 mL of water, displace with nitrogen, then stir and heat to reflux, stop heating after reacting for 24 h. After the reaction solution is cooled to room temperature, filter it, wash the filter cake with water, ethanol, and methyl tert-butyl ether three times respectively, collect the filter cake, and the filter cake is RD-1-1a. Add the collected filter cake to the flask, then add potassium carbonate (1.96 g) and ligand RP-13 (5.36 g) thereto, dissolve with 30 mL of dichloromethane, stir under nitrogen protection for 18 h, detect the completion of the reaction, stop the reaction, separate by column chromatography, and then slurry with ethanol and n-hexane to obtain 2.55 g of red solid.

[0243]

[0244] of Compound 1 1 1H NMR:

[0245] 1 1H NMR (400 MHz, chloroform-d) δ 8.81 (d, J = 9.8 Hz, 2H), 8.66–8.58 (m, 2H), 7.90 (d, J = 8.9 Hz, 2H), 7.80–7.72 (m, 5H), 7.54–7.42 (m, 5H), 7.26 (dd, J = 7.8, 1.1 Hz, 2H), 6.91–6.81 (m, 5H), 5.94 (s, 1H), 2.72 (p, J = 8.3 Hz, 1H), 2.57–2.36 (m, 15H), 1.85–1.58 (m, 7H), 1.62–1.47 (m, 6H), 1.45 (dddd, J = 9.8, 8.4, 4.7, 2.7 Hz, 1H).

[0246] 2. Compound 2: Synthesis of RDP-7

[0247] Step 1: Synthesis of auxiliary ligand RP-13

[0248] Synthesize RP-13 according to the same method as in Step 1 of the synthesis of Compound 1.

[0249]

[0250] Synthesize RD-1-2 according to the same method as in Steps 2-5 of the synthesis of Compound 1 (except replacing 2-fluorophenylboronic acid in Step 2 with 4-fluorophenylboronic acid), and obtain 5.28 g of white solid.

[0251]

[0252] Step 6: Synthesis of complex RDP-7

[0253] Synthesize RDP-7 according to the same method as in Step 6 of the synthesis of Compound 1 (except replacing ligand RD-1-1 with ligand RD-1-2), and obtain 2.31 g of red solid.

[0254]

[0255] For Compound 2 1 1H NMR:

[0256] 1 1H NMR (400 MHz, chloroform-d) δ 8.81 (d, J = 9.8 Hz, 2H), 8.61 (d, J = 9.6 Hz, 2H), 8.36 (dd, J = 9.2, 0.7 Hz, 2H), 7.99–7.88 (m, 5H), 7.50 (d, J = 8.9 Hz, 2H), 7.26 (dd, J = 9.1, 2.8 Hz, 2H), 6.87 (dd, J = 2.2, 1.0 Hz, 2H), 6.83 (d, J = 2.2 Hz, 2H), 5.94 (s, 1H), 2.72 (p, J = 8.3 Hz, 1H), 2.51 (p, J = 7.6 Hz, 1H), 2.42–2.35 (m, 15H), 1.85–1.40 (m, 14H).

[0257] 3. Synthesis of Compound 3: RDP-19

[0258] Step 1: Synthesis of auxiliary ligand RP-13

[0259] Synthesize RP-13 according to the same method as in Step 1 of the synthesis of Compound 1.

[0260]

[0261] Step 2: Synthesis of intermediate IP-10

[0262] 2-Chloro-4-iodopyridine-3-carbaldehyde (13.00 g), 3,4-difluorophenylboronic acid (8.44 g) and sodium bicarbonate (8.17 g) were added to a flask. Toluene (100 mL), ethanol (50 mL) and water (50 mL) were added. After purging with nitrogen, tetrakis(triphenylphosphine)palladium(0) (50 mg) was added, and then the mixture was heated under reflux with stirring for 4 h. After the reaction was completed, water and ethyl acetate were added for extraction. The organic phase was collected and separated by column chromatography to obtain 11.17 g of a white solid with a yield of 90.60%.

[0263] Step 3: Synthesis of intermediate IP-11

[0264] A flask was taken and methoxymethyl(triphenyl)phosphonium chloride (17.03 g) and toluene (150 mL) were added thereto. Potassium tert-butoxide (6.50 g) was added portionwise under an ice-water bath. After addition, stirring was continued under the ice-water bath for 1 h, and then intermediate IP-10 (10.50 g) dissolved in 50 mL of toluene was added dropwise. After the addition was completed, the ice-water bath was removed and stirring was continued for 2 h. After the reaction was completed, the reaction was quenched with water, and then extracted and washed with water and ethyl acetate for several times. The organic phase was collected and separated by column chromatography on the organic phase to obtain 9.34 g of a white solid with a yield of 80.09%.

[0265] Step 4: Synthesis of intermediate IP-12

[0266] A flask was taken and intermediate IP-11 (9.00 g) and dichloromethane (80 mL) were added thereto. After purging with nitrogen, methanesulfonic acid (24.56 g) was added dropwise thereto with stirring. After the addition was completed, stirring was continued at room temperature for 2 h. After the reaction was completed, the reaction was quenched with water. Extraction was carried out with dichloromethane and water, and the organic phase was collected and separated by column chromatography to obtain 7.21 g of a white solid with a yield of 90.27%.

[0267] Step 5: Synthesis of ligand RD-1-3

[0268] A flask was taken and intermediate IP-12 (7.00 g) and 3,5-dimethylphenylboronic acid (5.05 g) were added thereto. Toluene (50 mL), ethanol (25 mL) and water (25 mL) were added. After purging with nitrogen and stirring, X-PHOS (200 mg) and palladium(II) acetate (50 mg) were added, and the mixture was heated under reflux for 2 h. After detecting the completion of the reaction, heating was stopped. Water and ethyl acetate were added for extraction. The organic phase was collected and separated by column chromatography, and then recrystallized from ethanol to obtain 7.99 g of a white solid with a yield of 89.23%.

[0269]

[0270] Step 6: Synthesis of complex RDP-19

[0271] Take a flask, add ligand RD-1-3 (2.17 g) and iridium(III) chloride trihydrate (1.00 g) to it, add 30 mL of ethylene glycol monoethyl ether and 10 mL of water, displace with nitrogen, then stir and heat to reflux. Stop heating after reacting for 24 h. After the reaction solution is cooled to room temperature, filter it. Wash the filter cake with water, ethanol, and methyl tert-butyl ether three times respectively, and collect the filter cake. Add the collected filter cake to the flask, then add potassium carbonate (1.96 g) and ligand RP-13 (5.36 g) to it, dissolve with 30 mL of dichloromethane, stir for 18 h under nitrogen protection. Stop the reaction when the reaction is detected to be complete, separate by column chromatography, and then slurry with ethanol and n-hexane to obtain 2.21 g of a red solid.

[0272]

[0273] For compound 2 1 H NMR:

[0274] 1 H NMR (400 MHz, chloroform-d) δ 8.84 (d, J = 9.7 Hz, 2H), 8.69–8.60 (m, 2H), 8.01 (d, J = 0.7 Hz, 2H), 7.93 (dd, J = 8.9, 2.2 Hz, 2H), 7.90 (s, 2H), 7.75 (d, J = 2.2 Hz, 2H), 7.54–7.46 (m, 2H), 6.87 (dd, J = 2.1, 1.0 Hz, 2H), 6.83 (d, J = 2.2 Hz, 2H), 5.94 (s, 1H), 2.72 (p, J = 8.3 Hz, 1H), 2.57–2.36 (m, 14H), 1.85–1.39 (m, 15H).

[0275] 4. Synthesis of compound 4: RDP-28

[0276] Step 1: Synthesis of auxiliary ligand RP-13

[0277] Synthesize RP-13 according to the same method as step 1 in the synthesis of compound 1.

[0278]

[0279] Step 2: Synthesis of intermediate IP-13

[0280] Take a flask, add magnesium chips (11.34 g) and a grain of iodine into it. After purging with nitrogen, while stirring in an ice-water bath, slowly add a solution of 1-bromo-4-fluoronaphthalene (100.00 g) in tetrahydrofuran (500 mL). After the addition is complete, continue to stir in the ice-water bath for 30 min, then quickly add HPLC-grade DMF (35.73 g), controlling the temperature not to exceed 30 °C. After the addition is complete, remove the ice-water bath and continue to stir at room temperature for 1 h. Quench the reaction with water. Extract with saturated sodium bicarbonate solution and ethyl acetate, collect the organic phase, and separate by column chromatography to obtain 70.23 g of white solid with a yield of 90.75%.

[0281] Step 3: Synthesis of Intermediate IP-14

[0282] Take a flask, add Intermediate IP-13 (70.00 g) and aminoacetal (64.23 g) into it, then add 5 mL of concentrated hydrochloric acid dropwise, heat to 100 °C, stir for 2 h, then add toluene and perform rotary evaporation at least 3 times. After drying the solvent, obtain a brown solid, which is directly used in the next step without any treatment.

[0283] Step 4: Synthesis of Intermediate IP-15

[0284] Add trifluoroacetic anhydride (675.29 g) to the solid (IP-14) obtained in Step 3, then stir and heat to reflux. After 12 h, stop heating. Add n-hexane to the resulting mixture and separate by column chromatography to obtain 53.81 g of white solid with a yield of 67.89%.

[0285] Step 5: Synthesis of Intermediate IP-16

[0286] Take a flask, add Intermediate IP-15 (52.00 g) and dichloromethane (400 mL) into it. After purging with nitrogen, stir in an ice-water bath and gradually add 161.71 g of 30% phosphorus oxychloride dropwise. Then slowly add DMF (11.49 g) dropwise. After the addition is complete, remove the ice-water bath and continue to stir at room temperature for 18 h. After the reaction is complete, extract with saturated sodium bicarbonate solution and ethyl acetate, collect the organic phase, and separate by column chromatography to obtain 16.80 g of white solid with a yield of 27.50%.

[0287] Step 6: Synthesis of Ligand RD-3-1

[0288] Take a flask, add intermediate IP-16 (10.00 g) and 3,5-dimethylphenylboronic acid (7.12 g) to it, add toluene (50 mL), ethanol (25 mL) and water (25 mL), displace with nitrogen and stir, then add X-PHOS (200 mg) and palladium acetate (50 mg), heat under reflux for 2 h, detect the end of the reaction and stop heating. Add water and ethyl acetate for extraction, collect the organic phase, separate by column chromatography, and then recrystallize with ethanol to obtain 11.93 g of white solid, with a yield of 91.70%.

[0289]

[0290] Step 7: Synthesis of complex RDP-28

[0291] Take a flask, add ligand RD-1-3 (2.17 g) and iridium(III) chloride trihydrate (1.00 g) to it, add 30 mL of ethylene glycol monoethyl ether and 10 mL of water, displace with nitrogen, then stir and heat to reflux, stop heating after reacting for 24 h. After the reaction solution cools to room temperature, filter it, wash the filter cake with water, ethanol, and methyl tert-butyl ether 3 times respectively, and collect the filter cake. Add the collected filter cake to the flask, then add potassium carbonate (1.96 g) and ligand RP-13 (5.36 g) to it, dissolve with 30 mL of dichloromethane, stir under nitrogen protection for 18 h, detect the completion of the reaction, stop the reaction, separate by column chromatography, and then slurry with ethanol and n-hexane to obtain 2.23 g of red solid.

[0292]

[0293] For compound 4 1 1H NMR:

[0294] 1 1H NMR (400 MHz, chloroform-d) δ 8.75 (d, J = 10.1 Hz, 2H), 8.35 (dd, J = 7.2, 1.8 Hz, 2H), 7.95 (dd, J = 7.6, 1.6 Hz, 2H), 7.87 (dd, J = 10.2, 1.9 Hz, 2H), 7.70 (q, J = 1.0 Hz, 2H), 7.59–7.44 (m, 5H), 6.89 (dd, J = 2.2, 1.1 Hz, 2H), 6.83 (d, J = 2.2 Hz, 2H), 5.94 (s, 1H), 2.72 (p, J = 8.3 Hz, 1H), 2.51 (p, J = 7.6 Hz, 1H), 2.39 (d, J = 4.7 Hz, 13H), 1.85–1.38 (m, 16H).

[0295] 5. Synthesis of compound 5. RDP-42

[0296] Step 1: Synthesis of Auxiliary Ligand RP-13

[0297] Synthesize RP-13 according to the same method as in Step 1 of the synthesis of Compound 1.

[0298]

[0299] Step 2: Synthesis of Intermediate IP-17

[0300] Take a flask, add magnesium chips (9.55 g) and a grain of iodine into it. After purging with nitrogen, while stirring in an ice-water bath, slowly add a solution of 1-bromo-4-fluoro-6-isopropylnaphthalene (100.00 g) in tetrahydrofuran (500 mL). After the addition is complete, continue to stir in the ice-water bath for 30 min, then quickly add HPLC-grade DMF (30.10 g), controlling the temperature not to exceed 30 °C. After the addition is complete, remove the ice-water bath and continue to stir at room temperature for 1 h. Quench the reaction with water. Extract with saturated sodium bicarbonate solution and ethyl acetate, collect the organic phase, and separate by column chromatography to obtain 68.54 g of white solid, with a yield of 84.67%.

[0301] Step 3: Synthesis of Intermediate IP-18

[0302] Take a flask, add intermediate IP-17 (65.00 g) and aminoacetal (48.04 g) into it, then dropwise add 5 mL of concentrated hydrochloric acid, heat to 100 °C, stir for 2 h, then add toluene and evaporate it by rotary evaporation, repeat at least 3 times. After drying the solvent, obtain a brown solid, which is directly used in the next step without any treatment.

[0303] Step 4: Synthesis of Intermediate IP-19

[0304] Add trifluoroacetic anhydride (505.04 g) to the solid obtained in Step 3 (IP-18), then stir and heat to reflux. Stop heating after 12 h. Add n-hexane to the resulting mixture, and separate by column chromatography to obtain 42.99 g of white solid, with a yield of 72.52%.

[0305] Step 5: Synthesis of Intermediate IP-20

[0306] Take a flask, add intermediate IP-19 (40.00 g) and dichloromethane (400 mL) into it, purge with nitrogen, stir in an ice-water bath and dropwise add 161.71 g of 30% phosphorus oxychloride. Then slowly add DMF (7.28 g) dropwise. After the addition is complete, remove the ice-water bath and continue to stir at room temperature for 18 h. After the reaction is complete, extract with saturated sodium bicarbonate solution and ethyl acetate, collect the organic phase, and separate by column chromatography to obtain 12.12 g of white solid, with a yield of 26.49%.

[0307] Step 6: Synthesis of Ligand RD-3-2

[0308] Take a flask, add intermediate IP-20 (10.00 g) and 3,5-dimethylphenylboronic acid (6.03 g) into it, add toluene (50 mL), ethanol (25 mL) and water (25 mL), displace with nitrogen and stir, then add X-PHOS (200 mg) and palladium acetate (50 mg), heat under reflux for 2 h, detect the end of the reaction, and stop heating. Add water and ethyl acetate for extraction, collect the organic phase, separate by column chromatography, and then recrystallize with ethanol to obtain 10.87 g of white solid, with a yield of 86.64%.

[0309]

[0310] Step 7: Synthesis of Complex RDP-42

[0311] Take a flask, add ligand RD-3-2 (2.34 g) and iridium(III) chloride trihydrate (1.00 g) into it, add 30 mL of ethylene glycol monoethyl ether and 10 mL of water, displace with nitrogen, then stir and heat to reflux. After reacting for 24 h, stop heating. After the reaction solution cools to room temperature, filter it. Wash the filter cake with water, ethanol, and methyl tert-butyl ether three times respectively, and collect the filter cake. Add the collected filter cake into the flask, then add potassium carbonate (1.96 g) and ligand RP-13 (5.36 g) into it, dissolve with 30 mL of dichloromethane, stir under nitrogen protection for 18 h, detect the completion of the reaction, stop the reaction, separate by column chromatography, and then slurry with ethanol and n-hexane to obtain 2.06 g of red solid.

[0312]

[0313] For Compound 5 1 H NMR:

[0314] 11H NMR (400 MHz, chloroform-d) δ 8.75 (d, J = 10.1 Hz, 2H), 8.06 (d, J = 8.3 Hz, 2H), 7.88 (dd, J = 10.1, 2.0 Hz, 2H), 7.71 (q, J = 1.0 Hz, 2H), 7.49–7.43 (m, 2H), 7.31 (dd, J = 8.4, 2.1 Hz, 2H), 6.89 (dd, J = 2.2, 1.1 Hz, 2H), 6.83 (d, J = 2.1 Hz, 2H), 5.94 (s, 1H), 3.01–2.89 (m, 2H), 2.72 (p, J = 8.3 Hz, 1H), 2.51 (p, J = 7.6 Hz, 1H), 2.39 (d, J = 4.7 Hz, 13H), 1.85–1.39 (m, 17H), 1.27 (d, J = 4.6 Hz, 14H).

[0315] Compound 6: Synthesis of RDP-21

[0316] Step 1: Synthesis of auxiliary ligand RP-13

[0317] RP-13 was synthesized according to the same method as Step 1 in the synthesis of Compound 1.

[0318]

[0319] RD-1-4 was synthesized according to the same method as Steps 2-5 in the synthesis of Compound 3 (except that 3,4-difluorophenylboronic acid in Step 2 was replaced by 2,4-difluorophenylboronic acid), and 6.32 g of white solid was obtained.

[0320]

[0321] RDP-21 was synthesized according to the same method as Step 6 in the synthesis of Compound 1, and 2.38 g of red solid was obtained.

[0322]

[0323] For Compound 6 1 1H NMR:

[0324] 11H NMR (400 MHz, chloroform-d) δ 8.83 (d, J = 10.0 Hz, 2H), 8.60–8.52 (m, 2H), 7.69 (dd, J = 9.1, 2.2 Hz, 2H), 7.57 (t, J = 2.2 Hz, 2H), 7.50 (dd, J = 9.1, 0.7 Hz, 2H), 7.14 (d, J = 2.2 Hz, 2H), 6.91–6.81 (m, 5H), 5.94 (s, 1H), 2.72 (p, J = 8.2 Hz, 1H), 2.51 (p, J = 7.6 Hz, 1H), 2.42–2.35 (m, 15H), 1.85–1.36 (m, 14H).

[0325] 7. Compound 7: Synthesis of RDP-46

[0326] Step 1: Synthesis of auxiliary ligand RP-13

[0327] RP-13 was synthesized according to the same method as Step 1 in the synthesis of Compound 1.

[0328]

[0329] RD-1-5 was synthesized according to the same method as Steps 2 - 5 in the synthesis of Compound 1 (except that 2-fluorophenylboronic acid in Step 2 was replaced by 4-aminophenylboronic acid), and 3.28 g of a pale yellow solid was obtained.

[0330]

[0331] RDP-46 was synthesized according to the method of Step 6 in the synthesis of Compound 1, and 0.83 g of a red solid was obtained.

[0332]

[0333]

[0334] For Compound 7 1 1H NMR:

[0335] 11H NMR (400 MHz, chloroform-d) δ 8.81 (d, J = 9.7 Hz, 2H), 8.53 (d, J = 9.6 Hz, 2H), 8.00 (d, J = 8.2 Hz, 2H), 7.68 (dd, J = 8.9, 2.2 Hz, 2H), 7.43 (dd, J = 8.9, 0.7 Hz, 2H), 7.11 (t, J = 2.1 Hz, 2H), 7.00 (dd, J = 8.2, 2.2 Hz, 2H), 6.87 (dd, J = 2.2, 1.0 Hz, 2H), 6.83 (d, J = 2.2 Hz, 2H), 5.94 (s, 1H), 4.83 (d, J = 5.4 Hz, 2H), 4.72 (d, J = 5.4 Hz, 2H), 2.72 (p, J = 8.3 Hz, 1H), 2.51 (p, J = 7.6 Hz, 1H), 2.42–2.35 (m, 14H), 1.85–1.71 (m, 2H), 1.76–1.54 (m, 4H), 1.53 (ddddd, J = 8.7, 7.7, 5.9, 3.2, 1.5 Hz, 5H), 1.53–1.39 (m, 1H).

[0336] Compound 8: Synthesis of RDP-32

[0337] Step 1: Synthesis of auxiliary ligand RP-13

[0338] RP-13 was synthesized according to the same method as Step 1 in the synthesis of Compound 1.

[0339]

[0340] RD-3-3 was synthesized according to the same method as Steps 2 - 6 in the synthesis of Compound 4 (except that 1-bromo-4-fluoronaphthalene in Step 2 was replaced by 1-bromo-5-trifluoromethylnaphthalene), and 10.90 g of white solid was obtained.

[0341]

[0342] The iridium complex RDP-32 was synthesized according to the same method as Step 6 in the synthesis of Compound 1, and 2.71 g of red solid was obtained.

[0343]

[0344] For Compound 8 1 1H NMR:

[0345] 11H NMR (400 MHz, chloroform-d) δ 8.81–8.73 (m, 2H), 8.26–8.16 (m, 5H), 8.13–8.05 (m, 2H), 7.94–7.86 (m, 2H), 7.70 (dd, J = 9.0, 1.5 Hz, 2H), 7.63 (dd, J = 9.1, 6.9 Hz, 2H), 6.92–6.86 (m, 2H), 6.83 (d, J = 2.2 Hz, 2H), 5.94 (s, 1H), 2.72 (p, J = 8.2 Hz, 1H), 2.51 (p, J = 7.6 Hz, 1H), 2.42–2.35 (m, 14H), 1.85–1.70 (m, 3H), 1.75–1.55 (m, 4H), 1.60–1.45 (m, 7H), 1.50–1.36 (m, 1H).

[0346] Compound 9: Synthesis of RDP-47

[0347] Step 1: Synthesis of auxiliary ligand RP-13

[0348] RP-13 was synthesized according to the same method as Step 1 in the synthesis of Compound 1.

[0349]

[0350] RD-3-4 was synthesized according to the same method as Steps 2-6 in the synthesis of Compound 4 (except that 1-bromo-4-fluoronaphthalene in Step 2 was replaced by 1-bromo-5-methoxynaphthalene), and 11.05 g of white solid was obtained.

[0351]

[0352] The iridium complex RDP-47 was synthesized according to the same method as Step 6 in the synthesis of Compound 1, and 2.04 g of red solid was obtained.

[0353]

[0354] For Compound 9 1 1H NMR:

[0355] 11H NMR (400 MHz, chloroform-d) δ 8.77 (dd, J = 10.0, 0.6 Hz, 2H), 8.21 (dd, J = 8.0, 1.2 Hz, 2H), 8.16–8.08 (m, 2H), 8.08–8.00 (m, 2H), 7.83–7.76 (m, 2H), 7.40 (t, J = 7.8 Hz, 2H), 7.02–6.95 (m, 2H), 6.92–6.85 (m, 2H), 6.83 (d, J = 2.2 Hz, 2H), 5.94 (s, 1H), 3.90 (s, 6H), 2.71 (q, J = 8.3 Hz, 1H), 2.50 (q, J = 7.6 Hz, 1H), 2.42–2.35 (m, 14H), 1.85–1.64 (m, 5H), 1.66 (s, 0H), 1.68–1.60 (m, 1H), 1.64–1.55 (m, 1H), 1.60–1.49 (m, 6H), 1.54–1.48 (m, 1H), 1.53–1.36 (m, 1H).

[0356] Compound 10: Synthesis of RDP-48

[0357] Step 1: Synthesis of auxiliary ligand RP-13

[0358] RP-13 was synthesized according to the same method as in Step 1 of the synthesis of Compound 1.

[0359]

[0360] RD-3-5 was synthesized according to the same method as in Steps 2-6 of the synthesis of Compound 5 (except that 1-bromo-4-fluoro-6-isopropylnaphthalene in Step 2 was replaced with 1-bromo-6-isopropyl-7-fluoronaphthalene), and 11.74 g of white solid was obtained.

[0361]

[0362] The iridium complex RDP-48 was synthesized according to the same method as in Step 6 of the synthesis of Compound 1, and 2.82 g of red solid was obtained.

[0363]

[0364] For Compound 10 1 1H NMR:

[0365] 11H NMR (400 MHz, chloroform-d) δ 8.77 (d, J = 10.0 Hz, 2H), 8.28–8.20 (m, 2H), 8.09 (s, 2H), 7.88–7.76 (m, 5H), 7.42–7.35 (m, 2H), 6.92–6.85 (m, 2H), 6.83 (d, J = 2.3 Hz, 2H), 5.94 (s, 1H), 3.40 (heptd, J = 4.5, 0.7 Hz, 2H), 2.71 (q, J = 8.3 Hz, 1H), 2.50 (q, J = 7.6 Hz, 1H), 2.42–2.35 (m, 13H), 1.85–1.40 (m, 15H), 1.33 (d, J = 4.5 Hz, 14H).

[0366] 11. Compound 11: Synthesis of RDP-49

[0367] Step 1: Synthesis of auxiliary ligand RP-13

[0368] RP-13 was synthesized according to the same method as Step 1 in the synthesis of Compound 1.

[0369]

[0370] RD-3-6 was synthesized according to the same method as Steps 2-6 in the synthesis of Compound 10 (except that 1-bromo-6-isopropyl-7-fluoronaphthalene in Step 2 was replaced with 1-bromo-6-isopropyl-7-methylnaphthalene), and 10.36 g of white solid was obtained.

[0371]

[0372] The iridium complex RDP-49 was synthesized according to the same method as Step 6 in the synthesis of Compound 1, and 2.67 g of red solid was obtained.

[0373]

[0374] For Compound 11 1 1H NMR:

[0375] 11H NMR (400 MHz, chloroform-d) δ 8.81–8.73 (m, 2H), 8.17 (d, J = 1.0 Hz, 2H), 8.14–8.06 (m, 2H), 7.81–7.72 (m, 2H), 7.70–7.62 (m, 2H), 7.27 (dd, J = 2.2, 0.7 Hz, 2H), 6.88 (dt, J = 1.9, 1.0 Hz, 2H), 6.83 (d, J = 2.2 Hz, 2H), 5.94 (s, 1H), 3.36 (heptd, J = 4.2, 0.7 Hz, 2H), 2.71 (q, J = 8.3 Hz, 1H), 2.51 (p, J = 7.6 Hz, 1H), 2.43–2.35 (m, 19H), 1.85–1.40 (m, 13H), 1.51 (s, 4H), 1.29 (d, J = 4.1 Hz, 13H).

[0376] Compound 12: Synthesis of RDP-50

[0377] Step 1: Synthesis of auxiliary ligand RP-13

[0378] RP-13 was synthesized according to the same method as in Step 1 of the synthesis of Compound 1.

[0379]

[0380] RD-2-1 was synthesized according to the same method as in Steps 2-6 of the synthesis of Compound 4 (except that 1-bromo-4-fluoronaphthalene in Step 2 was replaced by 2-bromo-4-trifluoromethylnaphthalene), and 5.91 g of a pale yellow solid was obtained.

[0381]

[0382] The iridium complex RDP-50 was synthesized according to the same method as in Step 6 of the synthesis of Compound 1, and 2.07 g of a red solid was obtained.

[0383]

[0384]

[0385] For Compound 12 1 1H NMR:

[0386] 11H NMR (400 MHz, chloroform-d) δ 8.74 (s, 5H), 8.70–8.62 (m, 2H), 7.91 (dt, J = 7.7, 1.6 Hz, 2H), 7.75 (d, J = 1.9 Hz, 2H), 7.47–7.31 (m, 5H), 6.94 (d, J = 2.2 Hz, 2H), 6.90–6.84 (m, 2H), 5.94 (s, 1H), 2.72 (p, J = 8.2 Hz, 1H), 2.51 (p, J = 7.6 Hz, 1H), 2.42–2.35 (m, 14H), 1.85 –1.36 (m, 14H).

[0387] Compound 13: Synthesis of RDP-51

[0388] Step 1: Synthesis of auxiliary ligand RP-13

[0389] RP-13 was synthesized according to the same method as Step 1 in the synthesis of Compound 1.

[0390]

[0391] RD-2-2 was synthesized according to the same method as Steps 2-6 in the synthesis of Compound 4 (except that 1-bromo-4-fluoronaphthalene in Step 2 was replaced by 1-bromo-4-methoxynaphthalene), and 4.56 g of a pale yellow solid was obtained.

[0392]

[0393] The iridium complex RDP-51 was synthesized according to the same method as Step 6 in the synthesis of Compound 1, and 2.54 g of a red solid was obtained.

[0394]

[0395] For Compound 13 1 1H NMR:

[0396] 11H NMR (400 MHz, chloroform-d) δ 8.61 (d, J = 9.8 Hz, 2H), 8.40–8.32 (m, 2H), 7.96–7.85 (m, 2H), 7.69–7.59 (m, 2H), 7.59–7.53 (m, 2H), 7.48–7.37 (m, 5H), 6.91–6.84 (m, 2H), 6.76–6.70 (m, 2H), 5.94 (s, 1H), 4.13 (s, 6H), 2.71 (q, J = 8.3 Hz, 1H), 2.50 (q, J = 7.6 Hz, 1H), 2.42–2.35 (m, 14H), 1.85–1.74 (m, 1H), 1.79–1.60 (m, 5H), 1.64–1.55 (m, 1H), 1.54 (ddddd, J = 10.6, 8.8, 5.0, 2.0, 1.0 Hz, 7H), 1.53–1.36 (m, 1H).

[0397] Compound 14: Synthesis of RDP-52

[0398] Step 1: Synthesis of intermediate IP-52

[0399] Dissolve intermediate IP-51 (20.00 g) in tetrahydrofuran (50 mL). After purging with nitrogen, add methyllithium (1.60 mol / L, 178.30 mL) dropwise under an ice-water bath. After the addition, warm the reaction mixture to 30 °C and continue stirring for 12 h. Then stop the reaction. Extract with water and n-hexane, and evaporate the solvent to obtain 15.20 g of a pale yellow oily liquid with a yield of 82.26%.

[0400]

[0401] Step 2: Synthesis of auxiliary ligand RP-19

[0402] Take a single-necked flask, add DMF (100 mL), and then add potassium tert-butoxide (21.66 g) portionwise with stirring. Heat the mixture to 60 °C, and then add IP-52 (15.00 g) dropwise under nitrogen protection. After the addition, continue stirring for 20 min, and then add IP-51 (24.35 g) dropwise. After the addition of IP-51, continue stirring at 60 °C for 30 min, and then stop heating. Extract with water and n-hexane and wash several times. Collect the organic phase, evaporate the solvent by rotary evaporation, and separate by column chromatography to obtain 25.43 g of a white solid with a yield of 88.42%.

[0403]

[0404] Synthesize RD-1-1 according to the method of Steps 2-5 in the synthesis of Compound 1 to obtain 10.92 g of a white solid.

[0405]

[0406] According to the same method as in Step 6 of the synthesis of Compound 1, the iridium complex RDP-52 was synthesized to obtain 3.02 g of a red solid.

[0407]

[0408] 1H NMR of Compound 14:

[0409] 1 H NMR (400 MHz, chloroform-d) δ 8.81 (d, J = 10.0 Hz, 2H), 8.62–8.54 (m, 2H), 7.90 (d, J = 8.9 Hz, 2H), 7.80–7.72 (m, 2H), 7.54–7.43 (m, 4H), 7.26 (dd, J = 7.8, 1.1 Hz, 2H), 6.91–6.81 (m, 4H), 5.93 (s, 1H), 2.80–2.66 (m, 1H), 2.56–2.44 (m, 1H), 2.42–2.35 (m, 12H), 1.86–1.37 (m, 37H).

[0410]

[0411] Examples: OLED devices were respectively prepared using Compounds 1 - 14, denoted as Examples 1 - 14 accordingly. The device preparation steps are as follows:

[0412] (1) The transparent conductive ITO glass substrate 110 (with the anode 120 on it) (China Southern Glass Group Co., Ltd.) was ultrasonically treated in a commercial cleaning agent, rinsed in deionized water, then successively washed with ethanol, acetone, and deionized water, baked in a clean environment until all moisture was removed, cleaned with ultraviolet light and ozone, and then treated with oxygen plasma for 30 seconds;

[0413] (2) The glass substrate with the anode was placed in a vacuum chamber, evacuated, and HIL (10 nm) was evaporated on the ITO glass substrate as the hole injection layer 130 at a deposition rate of 0.1 nm / s;

[0414] (3) Compound HT was evaporated on the hole injection layer to form a 100 - nm - thick hole transport layer 140 at a deposition rate of 0.1 nm / s, and EB was evaporated to form a 50 - nm - thick electron blocking layer 150 at a deposition rate of 0.1 nm / s.

[0415] (4) A 35 - nm - thick light - emitting layer 160 was evaporated on the electron blocking layer, where RH was the host light - emitting material, and an iridium complex was used as the phosphorescent doping guest material at a weight ratio of 5%, and the deposition rate was 0.1 nm / s;

[0416] (5) Evaporate a 35-nm-thick compound ET:LiQ (weight ratio: 50:50) as the electron transport layer 170 on the light-emitting layer. The evaporation rate is 0.1 nm / s. Evaporate 1 nm of LiQ as the electron injection layer 180 and 100 nm of Al as the device cathode 190.

[0417]

[0418] Comparative Example 1: The only difference from Example 1 is that when preparing the device, Compound 1 is replaced with Ir-1.

[0419] Comparative Example 2: The only difference from Example 1 is that when preparing the device, Compound 1 is replaced with Ir-2.

[0420] Measure the operating voltage, current efficiency, CIE coordinates of the prepared device at a current density of 10 mA / cm 2 and the decay ratio of the brightness to the initial brightness, i.e., the LT(150) value, when operating at a current density of 50 mA / cm for 150 hours, to characterize the stability of the device. 2 Current density for 150 hours to characterize the stability of the device.

[0421] Table 1

[0422]

[0423] From the data comparison of the operating voltage, current efficiency, CIE coordinates, emission wavelength, and LT(150) values of Examples 1-14 and Comparative Examples 1-2, it can be seen that isoquinoline is further fused with aromatic rings and combined with an auxiliary ligand containing cycloalkanes. At a current density of 10 mA / cm 2 the operating voltage can be reduced to below 3.5 V, the luminous efficiency can be increased to above 20 cd / A, the emission wavelength has a certain red shift, and the LT(150) value can reach 88 or above, improving the stability of the device and extending the device life.

Claims

1. An iridium complex, characterized in that, The iridium complex has a structure represented by General Formula I: Wherein, The structure of Ring A is selected from any one of General Formulas RD-1 to RD-3: represents any integer from 0 to 8, and when a represents an integer ≥ 2, R1s are the same as or different from each other; R1, R2 and R5 are the same or different and each independently is H, deuterium, halogen, -CF3, CN, amino, substituted or unsubstituted C1-C 10 alkoxy or substituted or unsubstituted C1-C 30 alkyl, and the hydrogen in the alkyl chain of the C1-C 10 alkoxy and the C1-C 30 alkyl can each independently be substituted by deuterium, halogen, -CF3 or CN, where the halogen is selected from fluorine, chlorine, bromine or iodine; The R3 represents a C1-C 10 alkyl group; R4 represents H; and Auxiliary ligand Selected from any one of the following structures:

2. The iridium complex according to claim 1, wherein The general formula RD-1 contains 8 substitutable positions, and the substituent labels on the 8 substitutable positions are T 11 , T 12 , T 13 , T 14 , T 15 , T 16 , T 17 , and T 18 : wherein at least one of the T 11 -T 18 is not hydrogen, and at most three are not hydrogen The said T 11 -T 18 Any substituent other than hydrogen among them is selected from deuterium, halogen, -CF3, CN, amino group, substituted or unsubstituted C1-C 10 alkoxy group or substituted or unsubstituted C1-C4 alkyl group, and the hydrogen in the alkyl chain of the said C1-C 10 alkoxy group and the said C1-C4 alkyl group can each independently be substituted by deuterium, halogen, -CF3 or CN; The general formula RD-2 contains 8 substitutable positions, and the substituent labels on the 8 substitutable positions are T 21 , T 22 , T 23 , T 24 , T 25 , T 26 , T 27 , and T 28 , wherein at least one of the T 21 -T 28 is not hydrogen, and at most three are not hydrogen The T 21 -T 28 Any substituent other than hydrogen in the group is selected from deuterium, halogen, -CF3, CN, amino group, substituted or unsubstituted C1-C 10 alkoxy group or substituted or unsubstituted C1-C4 alkyl group, and the hydrogen in the alkyl chain of the C1-C 10 alkoxy group and the C1-C4 alkyl group can each independently be substituted by deuterium, halogen, -CF3 or CN; and The general formula RD-3 contains 8 replaceable positions, and the substituent labels on the 8 replaceable positions are T 31 、T 32 、T 33 、T 34 、T 35 、T 36 、T 37 、and T 38 , wherein at least one of the T 31 -T 38 is not hydrogen, and at most three are not hydrogen The T 31 -T 38 Any substituent other than hydrogen in the group is selected from deuterium, halogen, -CF3, CN, amino, substituted or unsubstituted C1-C 10 alkoxy or substituted or unsubstituted C1-C4 alkyl, and the hydrogen in the alkyl chain of the C1-C 10 alkoxy and the C1-C4 alkyl can each independently be substituted by deuterium, halogen, -CF3 or CN.

3. The iridium complex according to claim 1, wherein said R2 and R5 are the same or different and are each independently selected from H or C1-C 10 alkyl; said C1-C 10 alkyl is selected from methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl or n-decyl.

4. A method for preparing the iridium complex according to any one of claims 1-3, the method comprising the following steps: 1) Reacting a precursor substance with trivalent iridium to prepare a dimer; 2) Stirring and reacting the dimer with an auxiliary ligand compound and potassium carbonate or sodium carbonate in a solvent to obtain a compound of General Formula I; Wherein the structural formula of the precursor substance is as follows: Wherein the structural formula of the dimer is as follows: And Wherein the structural formula of the auxiliary ligand compound is as follows: Wherein: The structure of Ring A is selected from any one of General Formulas RD-1 to RD-3: a represents any integer from 0 to 8. When a represents an integer ≥ 2, R1s are the same or different from each other; R1, R2, and R5 are the same or different and each independently is H, deuterium, halogen, -CF3, CN, amino, substituted or unsubstituted C1-C 10 alkoxy, or substituted or unsubstituted C1-C 30 alkyl, wherein the hydrogen in the alkyl chain of the C1-C 10 alkoxy and the C1-C 30 alkyl can each independently be substituted by deuterium, halogen, -CF3, or CN, and wherein the halogen is selected from fluorine, chlorine, bromine, or iodine; R3 represents C1-C 10 alkyl; R4 represents H; and Auxiliary ligand in General Formula I Selected from any one of the following structures:

5. An organic electroluminescent device comprising the iridium complex according to any one of claims 1-3, the organic electroluminescent device comprising an anode, a cathode and an organic layer; the organic layer at least comprises a light-emitting layer, and the light-emitting layer comprises the iridium complex, and the iridium complex is doped in the light-emitting layer material as a light-emitting material.

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