Sulfur-containing boron-nitrogen compound and application thereof

Abstract

The invention provides a sulfur-containing boron-nitrogen compound and application thereof, the sulfur-containing boron-nitrogen compound has a structure as shown in a formula I or a formula II, the boron-nitrogen compound has a narrow spectrum, and is used as a luminescent material for preparing a luminescent layer of an organic electroluminescent device, and the prepared organic electroluminescent device shows high efficiency and high stability, and can be used as a luminescent material for preparing a luminescent layer of the organic electroluminescent device. Meanwhile, the emission spectrum of the device is narrow, the electroluminescence belongs to emission from orange red light to near infrared light, and the highest external quantum efficiency of electroluminescence of the device is as high as 20% or above.

Description

[0001] This application claims the priority of the patent application with the application number 202410066245.8. The filing date of the prior application is January 17, 2024, and the invention title is A Sulfur-Containing Boron-Nitrogen Compound and Its Application - Application to Priority. Technical Field

[0002] The present invention belongs to the technical field of organic electroluminescence, and relates to a sulfur-containing boron-nitrogen compound and its application. Background Art

[0003] Organic optoelectronic materials are a class of organic materials with properties such as the generation, conversion, and transmission of photons and electrons. Currently, the controllable optoelectronic properties of organic optoelectronic materials have been applied to organic light-emitting diodes (OLEDs), organic solar cells (OPVs), organic field effect transistors (OFETs), and even organic lasers. In recent years, OLEDs have become a very popular new type of flat panel display product at home and abroad. OLED displays have the characteristics of self-luminescence, wide viewing angles, short response times, high luminous efficiency, wide color gamuts, low operating voltages, thin panels, the ability to produce large-sized flexible panels, and low costs.

[0004] Regarding the history of organic electroluminescence, it can be traced back to the report by Bernanose et al. in 1953 (Holst G A, Kster T, Voges E, et al. FLOX—an oxygen-flux-measuring system using a phase-modulation method to evaluate the oxygen-dependent fluorescence lifetime, ScienceDirect. Sensors and Actuators B: Chemical, 1995, 29, 213.). Approximately 10 years later, in 1963, Pope et al. at New York University applied a voltage to a crystal of anthracene and observed the fluorescence emission of anthracene (M. Pope, H. Kallmann and P. Magnante, Electroluminescence in Organic Crystals, J. Chem. Phys., 1963, 38, 2042). In 1987, C.W. Tang et al. at Kodak Company in the United States used ultra-thin film technology, with an aromatic amine with good hole transport effect as the hole transport layer, an aluminum complex of 8-hydroxyquinoline as the light-emitting layer, indium tin oxide (ITO) film and metal alloy as the anode and cathode respectively, to fabricate a light-emitting device. This device achieved a brightness of up to 1000 cd / m at a driving voltage of 10V. 2For the green light emission, the efficiency of the device was 1.5 lm / W (C.W. Tang and S.A. Van Slyke, Organic electroluminescent diodes, Appl. Phys. Lett., 1987, 51, 913). This breakthrough progress enabled the rapid and in-depth development of organic electroluminescence research worldwide. In 1990, Burroughes et al. at the University of Cambridge proposed the first polymer (PPV)-based light-emitting diode, indicating that in a single-layer device, PPV can be used as a highly fluorescent emission material with a relatively high luminous efficiency (Burroughes J.H. et al., Light-emitting diodes based on conjugated polymers, Nature, 1990, 347, 539.). In 1998, Baldo and Forrest et al. at Princeton University reported the first phosphorescent device based on electroluminescence, which could in principle have an internal quantum yield of 100% (M.A. Baldo, D.F. O'Brien et al., Highly efficient phosphorescent emission from organic electroluminescent devices, Nature, 1998, 395, 151). However, on the one hand, phosphorescent materials generally use precious metals such as iridium and platinum, which are expensive. On the other hand, for deep blue phosphorescent materials, there are still problems such as chemical instability and significant efficiency roll-off at high current densities. Therefore, it is extremely important to develop an OLED device that uses inexpensive and stable organic small molecule materials and can achieve high-efficiency light emission.

[0005] In 2012, the research group of Adachi at Kyushu University reported a highly efficient all-fluorescent OLED device based on the thermally activated delayed fluorescence (TADF) mechanism (Uoyama H, Goushi K, Shizu K, et al. Highly efficient organic light-emitting diodes from delayed fluorescence, Nature, 2012, 492(7428):234 - 238.). When the energy level difference between the S1 and T1 of the molecule is small enough, triplet excitons can absorb thermal energy, return to the singlet state through the RISC process, and then emit fluorescence. The internal quantum efficiency (IQE) of its device can theoretically reach 100%, and the external quantum efficiency (EQE) is even as high as 30%, comparable to the level of phosphorescent devices. As the next-generation light-emitting materials, TADF materials have attracted wide attention in the industrial community due to their advantages of high efficiency and low cost, and the related research has broad prospects.

[0006] TADF molecules are mainly doped as guest materials in wide-bandgap host materials to achieve high-efficiency thermally activated delayed fluorescence (Q. Zhang, J. Li, K. Shizu, et al. Design of Efficient Thermally Activated Delayed Fluorescence Materials for Pure Blue Organic Light Emitting Diodes, J. Am. Chem. Soc. 2012, 134, 14706; H. Uoyama, K. Goushi, K. Shizu, H. Nomura, C. Adachi, Highly efficient organic light-emitting diodes from delayed fluorescence, Nature, 2012, 492, 234; T. Nishimoto, T. Yasuda, et al., A six-carbazole-decorated cyclophosphazene as a host with high triplet energy to realize efficient delayed-fluorescence OLEDs, Mater. Horiz., 2014, 1, 264). Different from the luminescence of traditional fluorescent molecule local (LE) states, TADF emission mainly originates from the transition of the ICT state. Therefore, it is easily affected by the vibration and rotation motion between the donor and acceptor, resulting in low electroluminescence efficiency, poor stability, and often a relatively wide emission spectrum, especially in the orange to near-infrared region (580 - 1000 nm), where the full width at half maximum of the emission spectrum is often greater than 80 nm. The above disadvantages lead to the inability of TADF-type orange to near-infrared light-emitting materials to meet the technical requirements of practical applications. Summary of the Invention

[0007] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a sulfur-containing boron nitride compound and its application. The compound provided by the present invention aims to solve the defects of TADF luminescent molecules in the long-wavelength region (above 580 nm), provide a luminescent material with high luminescence efficiency, good stability, and low cost (without precious metals), and be used to prepare the luminescent layer of an organic electroluminescent device to obtain a high-performance organic electroluminescent device.

[0008] To achieve the purpose of this invention, the following technical solutions are adopted by the present invention:

[0009] On the one hand, the present invention provides a sulfur-containing boron nitride compound, and the sulfur-containing boron nitride compound has a structure shown in the following formula I or formula II:

[0010]

[0011] R 1 、R 2 、R 3 、R 4 、R 5 、R 5 、R 7 and R 8 are independently selected from H, deuterium, C1-C20 alkyl, C1-C20 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, C6-C18 aryl substituted by one or more R a , 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted by one or more R a , diphenylamino, or diphenylamino substituted by one or more R a ;

[0012] R a is independently deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C12 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted by one or more R b , 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted by one or more R b , diphenylamino, or diphenylamino substituted by one or more R b ;

[0013] R b is independently deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted by one or more R c , 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted by one or more R c , diphenylamino, or diphenylamino substituted by one or more R c ;

[0014] R c is independently deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted by one or more R d , 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted by one or more R d , diphenylamino, or diphenylamino substituted by one or more R dSubstituted diphenylamino;

[0015] R d Each occurrence is independently deuterium, fluorine, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, or C6-C14 aryl substituted with one or more R e substituents;

[0016] R e Each occurrence is independently deuterium, fluorine, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, or C6-C14 aryl;

[0017] R 1 , R 2 , R 3 and R 4 exist independently or at least one of R 1 , R 2 , R 3 and R 4 forms a ring with the adjacent aromatic ring;

[0018] R 5 , R 5 , R 7 and R 8 exist independently or at least one of R 5 , R 5 , R 7 and R 8 forms a ring with the adjacent aromatic ring;

[0019] R 31 and R 32 are independently selected from H, deuterium, C1-C20 alkyl, C1-C20 alkoxy, C3-C10 cycloalkyl, C6-C18 aryl, C6-C18 aryl substituted with one or more R f substituents, 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted with one or more R f substituents, diphenylamino, or diphenylamino substituted with one or more R f substituents;

[0020] R f Each occurrence is independently deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C12 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted with one or more R g substituents, 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted with one or more R b substituents, diphenylamino, or diphenylamino substituted with one or more R g substituents;

[0021] R g Each occurrence is independently deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted with one or more R c substituted C6-C14 aryl, 5- to 18-membered heteroaryl;

[0022] R 31 can exist independently or form a ring with R;

[0023] R is C6-C18 aryl, C6-C18 aryl substituted with one or more R h substituted C6-C18 aryl, 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted with one or more R h substituted 5- to 18-membered heteroaryl, diphenylamino, or diphenylamino substituted with one or more R h substituted diphenylamino;

[0024] R h Each occurrence is independently deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C12 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted with one or more R i substituted C6-C14 aryl, 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted with one or more R i substituted 5- to 18-membered heteroaryl, diphenylamino, or diphenylamino substituted with one or more R i substituted diphenylamino;

[0025] R i Each occurrence is independently deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted with one or more R c substituted C6-C14 aryl, 5- to 18-membered heteroaryl;

[0026] E is S, When E is then R 6 is the same as R 7 and R 5 is the same as R 8 where the wavy line represents the attachment site of the group;

[0027] R 21 , R 22 , R 23 , R 24 , R 25 and R 26 are independently H, D (deuterium), F, CN, C1-C20 alkyl, C1-C20 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted with one or more R mSubstituted C6-C18 aryl, 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted with one or more R m 5- to 18-membered heteroaryl substituted with one or more R m diphenylamino, or diphenylamino substituted with one or more R

[0028] R m is independently, each occurrence, deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C12 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted with one or more R n 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted with one or more R n diphenylamino, or diphenylamino substituted with one or more R n ;

[0029] R n is independently, each occurrence, deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted with one or more R c 5- to 18-membered heteroaryl;

[0030] R 21 R 22 R 23 R 24 exist independently or at least two of them adjacent to each other form a ring (for example, R 21 and R 22 form a ring with each other, or R 22 and R 23 form a ring with each other, or R 23 and R 24 form a ring with each other), R 25 and R 26 exist independently or form a ring with each other;

[0031] The alkyl, alkoxy, cycloalkyl, aryl, heteroaryl are optionally substituted with one or more substituents selected from the following: halogen, -CN, C1-C12 alkyl, C1-C12 alkoxy, C1-C12 haloalkyl, C3-C10 cycloalkyl, C6-C14 aryl and 5- to 18-membered heteroaryl.

[0032] In some embodiments of the present invention, the luminescent compound is characterized in that the R 1 R 2 R 3 R 4 R 5 R 5 R 7 and R 8Independently H, D (deuterium), C1-C12 alkyl, C1-C 12 alkoxy, C3-C 10 cycloalkyl, phenyl, aryl substituted by at least one C1-C 12 alkyl, aryl substituted by at least one C1-C 12 alkoxy, phenyl-C1-C 12 alkyl, diphenylamino, diphenylamino substituted by at least one C1-C 12 alkyl, carbazolyl, carbazolyl substituted by at least one C1-C 12 alkyl;

[0033] Preferably, each occurrence of said R a is independently deuterium, fluorine, C1-C 12 alkyl, C1-C 12 alkoxy, C3-C 10 cycloalkyl, phenyl substituted by at least one C1-C 12 alkyl, phenyl substituted by at least one C1-C 12 alkoxy, phenyl-C1-C 12 alkyl, diphenylamino, diphenylamino substituted by at least one C1-C 12 alkyl, carbazolyl, carbazolyl substituted by at least one C1-C 12 alkyl;

[0034] Preferably, each occurrence of said R b is independently deuterium, fluorine, C1-C 12 alkyl, C1-C 12 alkoxy, C3-C 10 cycloalkyl, phenyl substituted by at least one C1-C 12 alkyl, phenyl substituted by at least one C1-C 12 alkoxy, phenyl-C1-C 12 alkyl, diphenylamino, diphenylamino substituted by at least one C1-C 12 alkyl, carbazolyl, carbazolyl substituted by at least one C1-C 12 alkyl;

[0035] Preferably, each occurrence of said R c is independently deuterium, fluorine, C1-C 12 alkyl, C1-C 12 alkoxy, C3-C 10 cycloalkyl, phenyl substituted by at least one C1-C 12 alkyl, phenyl substituted by at least one C1-C 12 alkoxy, phenyl-C1-C 12 alkyl, diphenylamino, diphenylamino substituted by at least one C1-C12 An alkyl-substituted diphenylamino group, a carbazolyl group, a C1-C 12 carbazolyl group substituted with an alkyl group;

[0036] Preferably, each occurrence of said R d is independently deuterium, fluorine, C1-C 12 alkyl group, C1-C 12 alkoxy group, C3-C 10 cycloalkyl group, a phenyl group substituted with at least one C1-C 12 alkyl group, a phenyl group substituted with at least one C1-C 12 alkoxy group, a carbazolyl group, a carbazolyl group substituted with at least one C1-C 12 alkyl group;

[0037] Preferably, said R 1 , R 2 , R 3 , R 4 , R 5 , R 5 , R 7 and R 8 are independently H, deuterium, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, hexyl, octyl, decyl, methoxy, ethoxy, butoxy, hexyloxy, cyclohexyl, adamantyl, phenyl, 2-methyl-phenyl, 4-methyl-phenyl, 4-ethyl-phenyl, 4-propyl-phenyl, 4-isopropylphenyl, 4-n-butylphenyl,

[0038] wherein the wavy line represents the attachment site of the group;

[0039] Preferably, said R 1 , R 2 , R 3 , R 4 , R 5 , R 5 , R 7 and R 8 are independently H, methyl, phenyl, 2-methyl-phenyl,

[0040] wherein the wavy line represents the attachment site of the group. Preferably, said R 1 , R 2 , R 3 , R 4 , R 5 , R5 , R 7 and R 8 is the same and is selected from any one of H, methyl, phenyl, 2-methyl-phenyl, ; wherein R j is H, methyl, isopropyl, tert-butyl or

[0041] Preferably, R 1 , R 2 , R 3 and R 4 at least one of them forms any one of the following ring structures with the connected aromatic ring:

[0042] wherein the bond where the * sign is located is the bond shared with the aromatic ring.

[0043] Preferably, R 5 , R 5 , R 7 and R 8 at least one of them forms any one of the following ring structures with the connected aromatic ring:

[0044] wherein the bond where the * sign is located is the bond shared with the aromatic ring.

[0045] Preferably, the said R 31 and R 32 are independently selected from H, deuterium, C1-C6 alkyl, C6-C18 aryl or C5-C18 heteroaryl;

[0046] Preferably, the said R is selected from C6-C18 aryl or 5- to 24-membered heteroaryl.

[0047] Preferably, the said R is selected from phenyl, biphenyl, phenyl-substituted biphenyl, wherein the wavy line represents the connection site of the group.

[0048] Preferably, E is S, wherein the wavy line represents the connection site of the group.

[0049] In some embodiments of the present invention, the sulfur-containing boron nitride compound is any one of the following compounds:

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068]

[0069] On the other hand, the present invention provides an organic electroluminescent material, and the organic electroluminescent material includes the boron nitride compound as described above.

[0070] On the other hand, the present invention provides an organic electroluminescent device, and the organic electroluminescent device includes an anode and a cathode, and an organic thin film layer disposed between the anode and the cathode, and the organic thin film layer includes the boron nitride compound as described above.

[0071] Preferably, the organic thin film layer includes a light-emitting layer, an optional hole injection layer, an optional hole transport layer, an optional electron transport layer, and an optional electron injection layer, and at least one of the light-emitting layer, the electron injection layer, the electron transport layer, the hole transport layer, and the hole injection layer includes the boron nitride compound as described above.

[0072] In the present invention, the boron nitride compound having the structures shown in Formula I and Formula II can be used as a functional material in at least one of a light-emitting layer, an electron injection layer, an electron transport layer, a hole transport layer, and a hole injection layer of an organic electroluminescent device.

[0073] In one embodiment, the organic electroluminescent device of the present invention may further include an optional hole blocking layer, an optional electron blocking layer, an optional capping layer, and the like.

[0074] In one embodiment, the organic electroluminescent device has a structure as shown in Figure 1 , wherein 1 is an ITO anode, 2 is a first hole transport layer, 3 is a second hole transport layer, 4 is a light-emitting layer, 5 is a second electron transport layer, 6 is a first electron transport layer, 7 is an electron injection layer, and 8 is a metal cathode.

[0075] In a certain embodiment, the boron nitride compound having the structure shown in Formula I is used to prepare the light-emitting layer in an organic electroluminescent device.

[0076] In a certain embodiment, the organic electroluminescent device further includes a substrate, and an anode layer, an organic light-emitting functional layer, and a cathode layer formed in sequence on the substrate; in the organic light-emitting functional layer, a light-emitting layer containing the boron nitride compound as described above is included, and may further include any one or a combination of a hole injection layer, a hole transport layer, an electron blocking layer, a hole blocking layer, an electron transport layer, and an electron injection layer.

[0077] On the other hand, the present invention provides an organic electroluminescent composition, which includes the above-mentioned boron nitride compound as a doping material and a host material;

[0078] Preferably, the host material is a material having electron transport ability and / or hole transport ability and whose triplet excited state energy is equal to or higher than the triplet excited state energy of the doping material.

[0079] In a preferred embodiment, the host material is any one of the compounds shown by Formula Trz1-A, Trz2-A, or Trz3-A.

[0080]

[0081] Z is N or CH;

[0082] wherein R z1 to R z10 are independently hydrogen, deuterium, F, CN, C1-C8 alkyl, C1-C8 alkoxy, C6-C 30 aryl, R za substituted C6-C 30 aryl, C6-C30 heteroaryl, or Rza group-substituted C6-C 30 heteroaryl;

[0083] R za is C1-C8 alkyl, C1-C8 alkoxy, C6-C 24 aryl or C6-C 24 heteroaryl;

[0084] R z9 or R z10 can exist independently or form a ring with the aromatic ring to which it is attached;

[0085] In one embodiment of the present invention, the organic electroluminescent composition is a light-emitting layer; the doping material in the organic electroluminescent composition is any one of the compounds represented by I or formula II (content: 0.3 wt%-30.0 wt%), and the host material (content: 99.7 wt%-70.0 wt%) is composed of any one of the compounds represented by formula Trz1-A, Trz2-A or Trz3-A.

[0086] In one embodiment of the present invention, the organic electroluminescent composition is a light-emitting layer; the doping material in the organic electroluminescent composition is any one of the compounds represented by BN-1 to BN-416 (content: 0.3 wt%-30.0 wt%), and the host material (content: 99.7 wt%-70.0 wt%) is composed of any one of the compounds represented by formula Trz1-A, Trz2-A or Trz3-A.

[0087] In one embodiment of the present invention, Trz1-A, Trz2-A or Trz3-A are the specific compounds represented by TRZ-1 to TRZ-48;

[0088]

[0089]

[0090]

[0091] In one embodiment of the present invention, the organic electroluminescent composition is a light-emitting layer; the doping material in the organic electroluminescent composition is any one of the compounds represented by I or formula II (content: 0.3 wt%-30.0 wt%), and the host material (content: 99.7 wt%-70.0 wt%) is composed of any one of the compounds represented by formula TRZ-1 to TRZ-48.

[0092] In one embodiment of the present invention, the organic electroluminescent composition is a light-emitting layer; the dopant material in the organic electroluminescent composition is any one of the compounds BN-1 to BN-416 (content: 0.3 wt% - 30.0 wt%), and the host material (content: 99.7 wt% - 70.0 wt%) is composed of any one of the compounds represented by Formulae TRZ-1 to TRZ-48.

[0093] In one embodiment of the present invention, the dopant material in the organic electroluminescent composition is any one of the compounds represented by Formula I or Formula II (content: 0.3 wt% - 30.0 wt%), and the host material (content: 99.7 wt% - 70.0 wt%) is composed of any one of the compounds represented by Formula Trz1-A, Trz2-A or Trz3-A and a phosphorescent compound containing metal Ir represented by Formula Ir-1 and Formula Ir-2. For example, in the host material, the weight ratio between the compound represented by Formula Trz1-A or Trz2-A and the phosphorescent compound containing metal Ir is 5:1 to 20:1, such as 5:1, 10:1, 11:1, 12:1, 13:1, 14:1, 15:1, 16:1, 17:1, 18:1, 19:1 or 20:1, etc.

[0094]

[0095] R ri independently represents hydrogen, deuterium, C1-C18 alkyl or C6-C18 aryl, where i is an integer from 1 to 22, and the dotted line represents that two of the four included bonds are double bonds spaced apart;

[0096] R ri any one of the groups can form a ring with the aromatic ring or aromatic heterocycle to which it is attached;

[0097] Preferably, the phosphorescent compound containing metal Ir is any one of the following compounds:

[0098]

[0099] In one embodiment of the present invention, the organic electroluminescent composition is a light-emitting layer; the doping material in the organic electroluminescent composition is any one of the compounds represented by Formulas BN-1 to BN-416 (content: 0.3 wt% - 30.0 wt%), and the host material (content: 99.7 wt% - 70.0 wt%) is composed of any one of the compounds represented by Formulas TTrz1-A, Trz2-A or Trz3-A and a phosphorescent compound containing metal Ir represented by Formulas Ir-1 and Ir-2. For example, in the host material, the weight ratio between the compound represented by Formulas Trz1-A or Trz2-A and the phosphorescent compound containing metal Ir is 5:1 to 20:1, such as 5:1, 10:1, 11:1, 12:1, 13:1, 14:1, 15:1, 16:1, 17:1, 18:1, 19:1 or 20:1, etc.

[0100] In one embodiment of the present invention, the organic electroluminescent composition is a light-emitting layer; the doping material in the organic electroluminescent composition is any one of the compounds represented by Formulas BN-1 to BN-416 (content: 0.3 wt% - 30.0 wt%), and the host material (content: 99.7 wt% - 70.0 wt%) is composed of any one of the compounds represented by Formulas Trz-1 to TRZ-48 and a phosphorescent compound containing metal Ir represented by Formulas Ir-1 and Ir-2. For example, in the host material, the weight ratio between the compound represented by Formulas Trz-1 to TRZ-48 and the phosphorescent compound containing metal Ir is 5:1 to 20:1, such as 5:1, 10:1, 11:1, 12:1, 13:1, 14:1, 15:1, 16:1, 17:1, 18:1, 19:1 or 20:1, etc.

[0101] On the other hand, the present invention provides an organic electroluminescent material, which includes the organic electroluminescent composition as described above.

[0102] On the other hand, the present invention provides an organic electroluminescent device, which includes an anode and a cathode, and an organic thin film layer disposed between the anode and the cathode, and the organic thin film layer includes the organic electroluminescent composition as described above.

[0103] Preferably, the organic thin film layer includes a light-emitting layer, an optional hole injection layer, an optional hole transport layer, an optional electron transport layer, and an optional electron injection layer, and at least one of the light-emitting layer, electron injection layer, electron transport layer, hole transport layer, and hole injection layer includes the organic electroluminescent composition as described above.

[0104] In the present invention, the organic electroluminescent composition can be used as a functional material in at least one of a light-emitting layer, an electron injection layer, an electron transport layer, a hole transport layer, and a hole injection layer of an organic electroluminescent device.

[0105] In one embodiment of the present invention, the material of the light-emitting layer in the organic electroluminescent device comprises the organic electroluminescent composition as described above.

[0106] In one embodiment of the present invention, the organic electroluminescent composition serves as the light-emitting layer, and the light-emitting principle of the light-emitting layer is based on energy transfer from the host material to any one of the compounds represented by Formula I or Formula II or carrier capture by the light-emitting material itself.

[0107] In one embodiment of the present invention, the organic electroluminescent device further includes a substrate, and an anode layer, an organic light-emitting functional layer, and a cathode layer formed sequentially on the substrate; in the organic light-emitting functional layer, a light-emitting layer containing the organic electroluminescent composition as described above is included, and any one or a combination of at least two of a hole injection layer, a hole transport layer, an electron blocking layer, a hole blocking layer, an electron transport layer, and an electron injection layer may also be included.

[0108] On the other hand, the present invention provides an application of the organic electroluminescent device as described above in an organic electroluminescent display or an organic electroluminescent lighting source.

[0109] Term Explanation

[0110] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0111] As used herein, the terms "comprising" or "including" can be open-ended, semi-closed, and closed. In other words, the terms also include "consisting essentially of...", or "consisting of...".

[0112] Group Definition

[0113] In this specification, groups and their substituents can be selected by those skilled in the art to provide stable structural moieties and compounds. When a substituent is described by a conventional chemical formula written from left to right, the substituent also includes the chemically equivalent substituent obtained when the structural formula is written from right to left.

[0114] The chapter headings used in this specification are only for the purpose of organizing the article and should not be construed as limiting the subject matter described. All documents or portions of documents cited in the present invention, including but not limited to patents, patent applications, articles, books, operating manuals, and theses, are hereby incorporated by reference in their entirety.

[0115] Unless otherwise specified, all technical and scientific terms used herein have the standard meanings in the field to which the claimed subject matter pertains. In the event of multiple definitions for a term, the definition provided herein shall prevail.

[0116] It should be understood that the singular forms, such as "a", used in the present invention include plural referents unless otherwise specified. Additionally, the term "comprising" is an open-ended limitation and not a closed one, i.e., it includes the content specified in the present invention but does not exclude other aspects.

[0117] Unless otherwise indicated, the present invention employs conventional methods of mass spectrometry and elemental analysis, and the steps and conditions can refer to the conventional operating steps and conditions in the art.

[0118] Unless otherwise specified, the present invention uses standard nomenclature and standard laboratory procedures and techniques in analytical chemistry, organic synthetic chemistry, and optics. In some cases, standard techniques are used for chemical synthesis, chemical analysis, and detection of the performance of light-emitting devices.

[0119] The compounds of the present invention may contain non-natural proportions of atomic isotopes on one or more atoms constituting the compound. For example, the compounds can be labeled with radioactive isotopes, such as deuterium (2H). All isotopic compositions of the compounds of the present invention, whether radioactive or not, are included within the scope of the present invention.

[0120] In the present invention, unless otherwise specified, the number of "substitutions" can be one or more; when there are multiple substitutions, it means more than two, for example, it can be 2, 3, or 4. And when the number of "substitutions" is multiple, the "substitutions" can be the same or different. In the present invention, the position of "substitution", unless otherwise specifically stated, can be arbitrary.

[0121] In the present invention, as a group or as part of another group (such as in groups like halogen-substituted alkyl groups), the term "alkyl" is meant to include saturated aliphatic hydrocarbon groups with branched and straight-chain forms having the specified number of carbon atoms. For example, C1-C 20Alkyl includes straight-chain or branched alkyl groups having 1 to 20 carbon atoms. As defined in "C1-C6 alkyl", it includes groups having 1, 2, 3, 4, 5, or 6 carbon atoms in a straight-chain or branched structure. For example, in the present invention, the C1-C6 alkyl groups are each independently methyl, ethyl, propyl, butyl, pentyl, or hexyl; among them, propyl is a C3 alkyl group (including isomers, such as n-propyl or isopropyl); butyl is a C4 alkyl group (including isomers, such as n-butyl, sec-butyl, isobutyl, or tert-butyl); pentyl is a C5 alkyl group (including isomers, such as n-pentyl, 1-methyl-butyl, 1-ethyl-propyl, 2-methyl-1-butyl, 3-methyl-1-butyl, isopentyl, tert-pentyl, or neopentyl); hexyl is a C6 alkyl group (including isomers, such as n-hexyl or isohexyl).

[0122] As used herein, the term "alkoxy" refers to an alkyl group as defined above that is connected via an oxygen bond (-O-).

[0123] In the present invention, as a group or part of other groups, the term "Cn-m aryl" refers to a monocyclic or polycyclic aromatic group (ring atoms are only carbon atoms) having n to m ring carbon atoms, which has at least one carbon ring with a conjugated π electron system. Examples of the above aryl units include phenyl, naphthyl, indenyl, azulenyl, fluorenyl, phenanthryl, or anthracenyl. In one embodiment, the aryl is preferably a C6-14 aryl, such as phenyl and naphthyl, and more preferably phenyl.

[0124] In the present invention, as a group or as part of another group, the term "n-m membered heteroaryl" refers to an aromatic group in which the ring atoms contain one or more (e.g., 1, 2, 3, and 4) heteroatoms selected from nitrogen, oxygen, and sulfur, and the ring atoms are n to m in number, and the heteroaryl is a monocyclic, bicyclic, tricyclic, or tetracyclic system, where at least one ring is an aromatic ring. Heteroaryls within this definition include, but are not limited to: acridinyl, carbazolyl, cinnolinyl, quinoxalinyl, pyrazolyl, indolyl, benzotriazolyl, furyl, thienyl, benzothienyl, benzofuryl, quinolinyl, isoquinolinyl, oxazolyl, isoxazolyl, pyrazinyl, pyridazinyl, pyridyl, pyrimidinyl, pyrrolyl, tetrahydroquinoline, imidazolyl, triazolyl, tetrazolyl, thiazolyl, isothiazolyl, furazanyl, thiadiazolyl, oxadiazolyl, pyridyl, pyrazinyl, pyridazinyl, pyrimidinyl, triazinyl, purinyl, pteridinyl, naphthyridinyl, quinazolinyl, phthalazinyl, imidazopyridyl, imidazothiazolyl, imidazoxazolyl, benzothiazolyl, benzoxazolyl, benzimidazolyl, isoindolyl, indazolyl, pyrrolopyridyl, thiophenopyridyl, furanopyridyl, benzothiadiazolyl, benzoxadiazolyl, pyrrolopyrimidinyl, thiophenofuryl. In one embodiment, as preferred examples of "5-18 membered heteroaryl", furyl, thienyl, pyrrolyl, imidazolyl, thiazolyl, pyrazolyl, oxazolyl, isoxazolyl, isothiazolyl, pyridyl, pyrimidinyl, and carbazolyl can be cited, and more preferably carbazolyl.

[0125] As used herein, the term Cn-Cm cycloalkyl refers to a monocyclic or polycyclic alkyl group having n to m carbon atoms, such as 3-C10 cycloalkyl and C3-C6 cycloalkyl. Examples include adamantyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and bicycloheptyl. In one embodiment, C3-C10 cycloalkyl is preferably adamantyl or cyclohexyl.

[0126] In the present invention, the defined carbon number range of the group means that it includes any integer number of carbon atoms within the defined range. For example, C1-C 20 means that the number of carbon atoms of the group can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20, and for C3-C 10 means that the number of carbon atoms of the group can be 3, 4, 5, 6, 7, 8, 9, or 10, and the defined carbon number range of other groups can be analogized.

[0127] On the basis of not violating the common knowledge in the art, the above preferred conditions can be arbitrarily combined to obtain various preferred examples of the present invention.

[0128] The reagents and raw materials used in the present invention are all commercially available.

[0129] Compared with the prior art, the present invention has the following beneficial effects:

[0130] The boron nitride compound of the present invention realizes fine adjustment of the spectrum and further improves the luminescence efficiency by expanding conjugation and introducing different ligands. The boron nitride compound of the present invention has a narrow spectrum and is used as a luminescent material for preparing the luminescent layer of an organic electroluminescent device. The organic electroluminescent device prepared therefrom exhibits high efficiency and high stability. At the same time, the emission spectrum of the device is also narrow, and the electroluminescence belongs to orange-red light to near-infrared emission, and the maximum external quantum efficiency of the electroluminescence of the device is as high as more than 20%. Description of the Drawings

[0131] Figure 1 It is a schematic structural diagram of a vacuum evaporation type organic electroluminescent device provided by the present invention. Among them, 1 is the ITO anode, 2 is the first hole transport layer, 3 is the second hole transport layer, 4 is the luminescent layer, 5 is the second electron transport layer, 6 is the first electron transport layer, 7 is the electron injection layer, and 8 is the metal cathode.

[0132] Figure 2 It is the electroluminescence spectrum of the device using the compound BN-21.

[0133] Figure 3 It is the electroluminescence spectrum of the device using the compound BN-31.

[0134] Figure 4 It is the electroluminescence spectrum of the device using the compound BN-313. Detailed Embodiments

[0135] The technical solution of the present invention will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments are only for helping to understand the present invention and should not be regarded as specific limitations of the present invention.

[0136] In the embodiments of the present invention, the raw materials used for synthesizing the shown compounds will be described below.

[0137] The specific raw material 1 includes the following molecules:

[0138]

[0139] The specific raw material 2 includes the following molecules:

[0140]

[0141]

[0142] The specific raw material 3 includes the following molecules:

[0143]

[0144] Synthetic route and reaction steps of general formula I are described:

[0145]

[0146]

[0147] First, using carbazole-based raw material Ai (A1 - A24) as the substrate, intermediate I-c-n (n = 1 - 416) is synthesized by the method reported in the previous patent. After NBS bromination reaction, intermediate I-d-n (n = 1 - 416) is obtained. Then, through a simple Suzuki reaction and coupling with arylboronic acid compounds, precursor I-e-n (n = 1 - 416) is obtained. Finally, sulfur is introduced into the compound under the catalysis of iodine to obtain the final product BN-n (n = 1 - 416).

[0148] In the first step, 20.0 mmol of raw material I-a-n (n = 1 - 416), 42.0 mmol of raw material Ai (A1 - A24), and 16.95 g of cesium carbonate (52.0 mmol) are added to 150 mL of anhydrous DMF (N,N-dimethylformamide). The reaction system is stirred at 160 °C for 18 hours, then cooled to room temperature and poured into ice water (2 L). The white solid is filtered by suction, dried in vacuo, and then further purified by column chromatography using a mixed eluent of dichloromethane / petroleum ether to obtain intermediate I-b-n (n = 1 - 416).

[0149] In the second step, under the protection of nitrogen atmosphere, 17.2 mL of a pentane solution of tert-butyllithium (22.4 mmol) is slowly added to 100 mL of a tert-butylbenzene solution containing 11.2 mmol of intermediate I-b-n (n = 1 - 416) at -30 °C. The temperature is slowly raised to 60 °C, and after stirring for 2 hours, pentane is removed in vacuo. Then it is cooled to -30 °C, 2.2 mL of boron tribromide (22.4 mmol) is added, and the reaction mixture is stirred at room temperature for 1 hour. Then, 3.7 mL of N,N-diisopropylethylamine (22.4 mmol) is added at 0 °C, and then the reaction mixture is heated to 130 °C and stirred for another 5 hours, and then cooled to room temperature. 5 mL of methanol is added to the reaction mixture to quench the residual boron tribromide. The reaction system is concentrated in vacuo and purified by column chromatography using a mixture of dichloromethane / petroleum ether as the eluent to obtain the target intermediate I-c-n (n = 1 - 416).

[0150] Step 3: Dissolve 4.0 mmol of compound I-c-n (n = 1 - 416) in 20 mL of dry chloroform. Slowly add 783 mg of NBS (4.4 mmol) to the above system under an ice-water bath. Degas and displace for 10 minutes. Then slowly raise the temperature to room temperature and continue the reaction for 4 hours. Extract the reaction mixture with dichloromethane and water, heat and rotary evaporate the organic phase under vacuum, and then purify it by column chromatography to obtain intermediate I-d-n (n = 1 - 416).

[0151] Step 4: Add arylboronic acid compound Bj (B1 - B12) (4.5 mmol), intermediate I-d-n (n = 1 - 416) (3.0 mmol), and 954 mg of potassium phosphate (4.5 mmol) to dry toluene (40 mL). Bubble the mixture with nitrogen for 10 minutes, and add 137 mg of tris(dibenzylideneacetone)dipalladium(0) (0.05 mmol) and 123 mg of S-Phos (0.1 mmol) under a high-flow nitrogen atmosphere. Heat the mixture to 90 °C and stir for 16 hours. After the reaction system cools to room temperature, extract the reaction mixture with dichloromethane and water, heat and rotary evaporate the organic phase under vacuum, and then purify it by column chromatography to obtain precursor I-e-n (n = 1 - 416).

[0152] Step 5: Dissolve 1.5 mmol of precursor I-e-n (n = 1 - 416), 50 mg of iodine (0.2 mmol), and 192 mg of sulfur (6.0 mmol) in 10 mL of dry o-dichlorobenzene. Bubble the mixture with nitrogen for 5 minutes, then heat the system to 190 °C and stir for 72 hours. After cooling to room temperature, wash the system with saturated aqueous sodium sulfite solution, extract with dichloromethane, heat and rotary evaporate the organic phase under vacuum, and then purify it by column chromatography using a mixed eluent of dichloromethane / petroleum ether to obtain the target product BN-n (n = 1 - 416).

[0153] Taking compound BN-26 as an example to illustrate the specific details of the synthesis example experiment:

[0154] Step 1: Add 3.86 g of raw material I-a-26 (1-bromo-2,6-difluorobenzene, 20.0 mmol), 11.74 g of raw material A3 (42.0 mmol), and 16.95 g of cesium carbonate (52.0 mmol) to 150 mL of anhydrous DMF (N,N-dimethylformamide). Stir the reaction system at 160 °C for 18 hours, then cool to room temperature and pour it into ice water (2 L). Filter out the solid, dry it in vacuo, and then further purify it by column chromatography using a mixed eluent of dichloromethane / petroleum ether to obtain 13.52 g of intermediate I-b-26 as a white solid with a yield of 95%.

[0155] Step 2: Under the protection of nitrogen atmosphere, 17.2 mL of a pentane solution of tert-butyllithium (22.4 mmol) was slowly added to 100 mL of a tert-butylbenzene solution containing 7.97 g of intermediate I-b-26 (11.2 mmol) at -30 °C. The temperature was slowly raised to 60 °C, and after stirring for 2 hours, pentane was removed under vacuum. Then it was cooled to -30 °C, 2.2 mL of boron tribromide (22.4 mmol) was added, and the reaction mixture was stirred at room temperature for 1 hour. Then 3.7 mL of N,N-diisopropylethylamine (22.4 mmol) was added at 0 °C, and then the reaction mixture was heated to 130 °C and stirred for another 5 hours, and then cooled to room temperature. 5 mL of methanol was added to the reaction mixture to quench the residual boron tribromide. The reaction system was concentrated under vacuum and purified by column chromatography using a mixture of dichloromethane / petroleum ether as the eluent to obtain 3.73 g of intermediate I-c-26 as a yellow solid with a yield of 52%.

[0156] Step 3: 2.56 g of compound I-c-26 (4.0 mmol) was dissolved in 20 mL of dry chloroform. Under an ice-water bath, 783 mg of NBS (4.4 mmol) was slowly added to the above system. The gas was removed and replaced for 10 minutes. Then it was slowly raised to room temperature and the reaction continued for 4 hours. The reaction mixture was extracted with dichloromethane and water, the organic phase was heated and dried under vacuum, and then purified by column chromatography to obtain 2.36 g of intermediate I-d-26 as an orange-yellow solid with a yield of 82%.

[0157] Step 4: 1.63 g of compound B6 (4.5 mmol), 2.16 g of intermediate I-d-26 (3.0 mmol), and 954 mg of potassium phosphate (4.5 mmol) were added to dry toluene (40 mL). The mixture was bubbled with nitrogen for 10 minutes, and 137 mg of tris(dibenzylideneacetone)dipalladium (0.05 mmol) and 123 mg of S-Phos (0.1 mmol) were added under a high-flow nitrogen atmosphere. The mixture was heated to 90 °C and stirred for 16 hours. After the reaction system was cooled to room temperature, the reaction mixture was extracted with dichloromethane and water, the organic phase was heated and dried under vacuum, and then purified by column chromatography to obtain 1.89 g of precursor I-e-26 as a yellow solid with a yield of 66%.

[0158] Step 5: Dissolve 1.44 g of precursor I-e-26 (1.5 mmol), 50 mg of iodine (0.2 mmol), and 192 mg of sulfur (6.0 mmol) in 10 mL of dry o-dichlorobenzene. Bubble the mixture with nitrogen for 5 minutes, then heat the system to 190 °C and stir for 72 hours. After cooling to room temperature, wash the system with saturated aqueous sodium sulfite solution, extract with dichloromethane, heat and spin-dry the organic phase under vacuum, and then purify by column chromatography using a mixed eluent of dichloromethane / petroleum ether to obtain 1.07 g of the target product BN-26, a pink solid, with a yield of 72%.

[0159] Synthetic route and reaction steps description of general formula II-1:

[0160]

[0161]

[0162] First, use carbazole-based raw materials Ai (A1 - A24) as substrates to synthesize intermediate II-c-n (n = 1 - 416) by the method reported in the previous patent. Obtain intermediate II-d-n (n = 1 - 416) through NBS bromination reaction, then couple with arylboronic acid compounds through a one-step simple Suzuki reaction to obtain intermediate II-e-n (n = 1 - 416), then obtain precursor II-f-n (n = 1 - 416) through oxidative coupling reaction, and finally introduce sulfur into the compound under the catalysis of iodine to obtain the final product BN-n (n = 1 - 416).

[0163] Step 1: Add 20.0 mmol of raw material II-a-n (n = 1 - 416), 42.0 mmol of raw material Ai (A1 - A24), and 16.95 g of cesium carbonate (52.0 mmol) to 150 mL of anhydrous DMF (N,N-dimethylformamide). Stir the reaction system at 160 °C for 18 hours, then cool to room temperature and pour into ice water (2 L). Filter out the white solid, dry it in vacuo, and then further purify by column chromatography using a mixed eluent of dichloromethane / petroleum ether to obtain intermediate II-b-n (n = 1 - 416).

[0164] Step 2: Under the protection of nitrogen atmosphere, 17.2 mL of a pentane solution of tert-butyllithium (22.4 mmol) was slowly added to 100 mL of a tert-butylbenzene solution containing 11.2 mmol of intermediate II-b-n (n = 1 - 416) at -30 °C. The temperature was slowly raised to 60 °C, and after stirring for 2 hours, pentane was removed under vacuum. Then it was cooled to -30 °C, 2.2 mL of boron tribromide (22.4 mmol) was added, and the reaction mixture was stirred at room temperature for 1 hour. Then 3.7 mL of N,N-diisopropylethylamine (22.4 mmol) was added at 0 °C, and then the reaction mixture was heated to 130 °C and stirred for another 5 hours, and then cooled to room temperature. 5 mL of methanol was added to the reaction mixture to quench the residual boron tribromide. The reaction system was concentrated under vacuum and purified by column chromatography with a mixture of dichloromethane / petroleum ether as the eluent to obtain the target intermediate II-c-n (n = 1 - 416).

[0165] Step 3: 4.0 mmol of compound II-c-n (n = 1 - 416) was dissolved in 20 mL of dry chloroform. Under an ice-water bath, 783 mg of NBS (4.4 mmol) was slowly added to the above system. The system was degassed and replaced for 10 minutes. Then it was slowly raised to room temperature and the reaction continued for 4 hours. The reaction mixture was extracted with dichloromethane and water. The organic phase was heated and dried under vacuum by rotary evaporation, and then purified by column chromatography to obtain intermediate II-d-n (n = 1 - 416).

[0166] Step 4: The arylboronic acid compound Bj (B1 - B12) (4.5 mmol), intermediate II-d-n (n = 1 - 416) (3.0 mmol), and 954 mg of potassium phosphate (4.5 mmol) were added to dry toluene (40 mL). The mixture was bubbled with nitrogen for 10 minutes, and 137 mg of tris(dibenzylideneacetone)dipalladium(0) (0.05 mmol) and 123 mg of S-Phos (0.1 mmol) were added under a high-flow nitrogen atmosphere. The mixture was heated to 90 °C and stirred for 16 hours. After the reaction system was cooled to room temperature, the reaction mixture was extracted with dichloromethane and water. The organic phase was heated and dried under vacuum by rotary evaporation, and then purified by column chromatography to obtain intermediate II-e-n (n = 1 - 416).

[0167] Step 5: 1.5 mmol of intermediate II-e-n (n = 1 - 416) and 567.5 mg of DDQ (2.5 mmol) were dissolved in 20 mL of dry dichloromethane. The mixture was bubbled with nitrogen for 10 minutes and stirred at room temperature for 10 minutes. Then 0.75 mL of methanesulfonic acid was added dropwise to the system at 0 °C, and then stirred at room temperature for 4 hours. The reaction mixture was extracted with dichloromethane and water. The organic phase was heated and dried under vacuum by rotary evaporation, and then purified by column chromatography to obtain precursor II-f-n (n = 1 - 416).

[0168] Step 6: Dissolve 0.7 mmol of Intermediate II-f-n (n = 1 - 416), 25 mg of iodine (0.1 mmol), and 96 mg of sulfur (3.0 mmol) in 8 mL of dry o-dichlorobenzene. Bubble the mixture with nitrogen for 5 minutes, then heat the system to 190 °C and stir for 72 hours. After cooling to room temperature, wash the system with saturated aqueous sodium sulfite solution, extract with dichloromethane, heat and spin-dry the organic phase under vacuum, and then purify by column chromatography using a mixed eluent of dichloromethane / petroleum ether to obtain the target product BN-n (n = 1 - 416).

[0169] Taking compound BN-74 as an example to illustrate the specific details of the synthesis example experiment:

[0170] Step 1: Add 3.86 g of raw material II-a-74 (20.0 mmol of 1-bromo-2,6-difluorobenzene), 16.95 g of raw material A4 (42.0 mmol), and 16.95 g of cesium carbonate (52.0 mmol) to 150 mL of anhydrous DMF (N,N-dimethylformamide). Stir the reaction system at 160 °C for 18 hours, then cool to room temperature and pour it into ice water (2 L). Filter out the solid, dry it in vacuo, and then further purify by column chromatography using a mixed eluent of dichloromethane / petroleum ether to obtain 17.67 g of Intermediate II-b-74 as a white solid with a yield of 92%.

[0171] Step 2: Under a nitrogen atmosphere, slowly add 17.2 mL of a pentane solution of tert-butyllithium (22.4 mmol) to 100 mL of a tert-butylbenzene solution containing 10.75 g of Intermediate II-b-74 (11.2 mmol) at -30 °C. Slowly warm up to 60 °C, stir for 2 hours, then remove pentane under vacuum, and then cool to -30 °C. Add 2.2 mL of boron tribromide (22.4 mmol), and stir the reaction mixture at room temperature for 1 hour. Then add 3.7 mL of N,N-diisopropylethylamine (22.4 mmol) at 0 °C, and then raise the reaction mixture to 130 °C and continue to stir for 5 hours, and then cool to room temperature. Add 5 mL of methanol to the reaction mixture to quench the residual boron tribromide. Concentrate the reaction system under vacuum and purify by column chromatography using a mixture of dichloromethane / petroleum ether as the eluent to obtain 4.58 g of Intermediate II-c-74 as a yellow solid with a yield of 46%.

[0172] Step 3: Dissolve 3.56 g of compound II-c-74 (4.0 mmol) in 20 mL of dry chloroform. Under an ice-water bath, slowly add 783 mg of NBS (4.4 mmol) to the above system. Degas and displace for 10 minutes. Then slowly raise the temperature to room temperature and continue the reaction for 4 hours. Extract the reaction mixture with dichloromethane and water, heat and spin-dry the organic phase under vacuum, and then purify it by column chromatography to obtain 3.37 g of intermediate II-d-74, which is an orange solid with a yield of 87%.

[0173] Step 4: Add 891 mg of compound B3 (4.5 mmol), 2.90 g of intermediate II-d-74 (3.0 mmol), and 954 mg of potassium phosphate (4.5 mmol) to dry toluene (40 mL). Bubble the mixture with nitrogen for 10 minutes, and add 137 mg of tris(dibenzylideneacetone)dipalladium(0) (0.05 mmol) and 123 mg of S-Phos (0.1 mmol) under a high-flow nitrogen atmosphere. Heat the mixture to 90 °C and stir for 16 hours. After the reaction system cools to room temperature, extract the reaction mixture with dichloromethane and water, heat and spin-dry the organic phase under vacuum, and then purify it by column chromatography to obtain 2.22 g of intermediate II-e-74, which is a yellow solid with a yield of 71%.

[0174] Step 5: Dissolve 1.56 g of intermediate II-e-74 (1.5 mmol) and 567.5 mg of DDQ (2.5 mmol) in 20 mL of dry dichloromethane. Bubble the mixture with nitrogen for 10 minutes and stir at room temperature for 10 minutes; then add 0.75 mL of methanesulfonic acid dropwise to the system at 0 °C and stir at room temperature for another 4 hours. Extract the reaction mixture with dichloromethane and water, heat and spin-dry the organic phase under vacuum, and then purify it by column chromatography to obtain 982 mg of precursor II-f-74, which is a yellow solid with a yield of 63%.

[0175] Step 6: Dissolve 727 mg of precursor II-f-74 (0.7 mmol), 25 mg of iodine (0.1 mmol), and 96 mg of sulfur (3.0 mmol) in 8 mL of dry o-dichlorobenzene. Bubble the mixture with nitrogen for 5 minutes, and then heat the system to 190 °C and stir for 72 hours. After cooling to room temperature, wash the system with a saturated aqueous sodium sulfite solution and extract with dichloromethane. Heat and spin-dry the organic phase under vacuum, and then purify it by column chromatography using a mixed eluent of dichloromethane / petroleum ether to obtain 509 mg of the target product BN-74, which is a pink solid with a yield of 68%.

[0176] Synthetic route and reaction steps description of general formula II-2:

[0177]

[0178]

[0179] First, using carbazole-based raw materials Ai (A1 - A24) as substrates, intermediate III-b-n (n = 1 - 416) is obtained through a C-N coupling reaction. After consecutive substitution reactions and cyclization reactions, intermediate III-c-n (n = 1 - 416) is obtained. Then, through lithiation, boration, and cyclization reactions, precursor III-d-n (n = 1 - 416) is obtained. Finally, sulfur is introduced into the compound under the catalysis of iodine to obtain the final product BN-n (n = 1 - 416).

[0180] In the first step, 20.0 mmol of raw material III-a-n (n = 1 - 416), 42.0 mmol of raw material Ai (A1 - A24), and 16.95 g of cesium carbonate (52.0 mmol) are added to 150 mL of anhydrous DMF (N,N-dimethylformamide). The reaction system is stirred at 160 °C for 18 hours, then cooled to room temperature and poured into ice water (2 L). The white solid is filtered out, dried in vacuo, and then further purified by column chromatography using a mixed eluent of dichloromethane / petroleum ether to obtain intermediate III-b-n (n = 1 - 416).

[0181] In the second step, under the protection of a nitrogen atmosphere, 4.5 mL of a hexane solution of n-butyllithium (2.5 mol / L, 11.2 mmol) is slowly added to a 100 mL tetrahydrofuran solution containing 11.2 mmol of intermediate III-b-n (n = 1 - 416) (-78 °C). After maintaining -78 °C and stirring for 2 hours, a 20 mL tetrahydrofuran solution containing 12.0 mmol of compound Ck (k = 1 - 4) is slowly dropped into the system. The system is slowly warmed to room temperature and stirred for 10 hours. The reaction system is extracted with ethyl acetate and water. The ethyl acetate layer is separated and the organic phase is heated and evaporated to dryness under vacuum. The obtained crude product is dissolved in 80 mL of dichloromethane, and 2.0 mL of boron trifluoride diethyl ether complex is slowly added dropwise at room temperature. After stirring for 8 hours, the reaction is quenched with 30 mL of aqueous sodium bicarbonate solution. The reaction mixture is extracted with dichloromethane and water, and the organic phase is heated and evaporated to dryness under vacuum, and then purified by column chromatography to obtain intermediate III-c-n (n = 1 - 416).

[0182] Step 3: Under the protection of nitrogen atmosphere, 6.2 mL of a pentane solution of tert-butyllithium (8.0 mmol) was slowly added to 40 mL of a tert-butylbenzene solution containing 4.0 mmol of intermediate III-c-n (n = 1 - 416) at -30 °C. The temperature was slowly raised to 60 °C, and after stirring for 2 hours, pentane was removed under vacuum. Then, it was cooled to -30 °C, 0.8 mL of boron tribromide (8.0 mmol) was added, and the reaction mixture was stirred at room temperature for 1 hour. Then, 1.3 mL of N,N-diisopropylethylamine (8.0 mmol) was added at 0 °C, and then the reaction mixture was heated to 130 °C and stirred for another 5 hours, and then cooled to room temperature. 5 mL of methanol was added to the reaction mixture to quench the residual boron tribromide. The reaction system was concentrated under vacuum and purified by column chromatography using a mixture of dichloromethane / petroleum ether as the eluent to obtain precursor III-d-n (n = 1 - 416).

[0183] Step 4: 1.5 mmol of precursor III-d-n (n = 1 - 416), 50 mg of iodine (0.2 mmol), and 192 mg of sulfur (6.0 mmol) were dissolved in 10 mL of dry o-dichlorobenzene. The mixture was bubbled with nitrogen for 5 minutes, and then the system was heated to 190 °C and stirred for 72 hours. After cooling to room temperature, the system was washed with a saturated aqueous solution of sodium sulfite and extracted with dichloromethane. The organic phase was heated and dried under vacuum, and then purified by column chromatography using a mixture of dichloromethane / petroleum ether as the eluent to obtain the target product BN-n (n = 1 - 416).

[0184] Taking compound BN-51 as an example to illustrate the specific details of the synthesis example experiment:

[0185] Step 1: 4.55 g of raw material III-a-51 (20.0 mmol of 1-bromo-3-chloro-2,4-difluorobenzene), 14.57 g of raw material A5 (42.0 mmol), and 16.95 g of cesium carbonate (52.0 mmol) were added to 150 mL of anhydrous DMF (N,N-dimethylformamide). The reaction system was stirred at 160 °C for 18 hours, then cooled to room temperature, and poured into ice water (2 L). The solid was filtered out, dried in vacuo, and then further purified by column chromatography using a mixture of dichloromethane / petroleum ether as the eluent to obtain 15.52 g of intermediate III-b-51, which was a white solid with a yield of 88%.

[0186] Step 2: Under the protection of nitrogen atmosphere, 4.5 mL of a hexane solution of n-butyllithium (2.5 mol / L, 11.2 mmol) was slowly added to a 100 mL tetrahydrofuran solution containing 9.88 g of intermediate III-b-51 (11.2 mmol) at -78 °C. After maintaining at -78 °C and stirring for 2 hours, a 20 mL tetrahydrofuran solution containing 2.16 g of compound C3 (12.0 mmol) was slowly dropped into the system. The system was slowly warmed to room temperature and stirred for 10 hours. The reaction system was extracted with ethyl acetate and water. The ethyl acetate layer was separated and the organic phase was heated and rotary evaporated under vacuum. The obtained crude product was dissolved in 80 mL of dichloromethane, and 2.0 mL of boron trifluoride diethyl ether complex was slowly added dropwise at room temperature. After stirring for 8 hours, the reaction was quenched with 30 mL of aqueous sodium bicarbonate solution. The reaction mixture was extracted with dichloromethane and water, and the organic phase was heated and rotary evaporated under vacuum, and then purified by column chromatography to obtain 7.89 g of intermediate III-c-51 as a white solid, with a yield of 73%.

[0187] Step 3: Under the protection of nitrogen atmosphere, 6.2 mL of a pentane solution of tert-butyllithium (8.0 mmol) was slowly added to a 40 mL tert-butylbenzene solution containing 3.86 g of intermediate III-c-51 (4.0 mmol) at -30 °C. The temperature was slowly raised to 60 °C, and after stirring for 2 hours, pentane was removed under vacuum, and then cooled to -30 °C. 0.8 mL of boron tribromide (8.0 mmol) was added, and the reaction mixture was stirred at room temperature for 1 hour. Then 1.3 mL of N,N-diisopropylethylamine (8.0 mmol) was added at 0 °C, and then the reaction mixture was raised to 130 °C and stirred for another 5 hours, and then cooled to room temperature. 5 mL of methanol was added to the reaction mixture to quench the residual boron tribromide. The reaction system was concentrated under vacuum and purified by column chromatography using a dichloromethane / petroleum ether mixture as the eluent to obtain 2.13 g of precursor III-d-51 as a yellow solid, with a yield of 57%.

[0188] Step 4: 1.40 g of precursor III-d-51 (1.5 mmol), 50 mg of iodine (0.2 mmol), and 192 mg of sulfur (6.0 mmol) were dissolved in 10 mL of dry o-dichlorobenzene. The mixture was bubbled with nitrogen for 5 minutes, and then the system was heated to 190 °C and stirred for 72 hours. After cooling to room temperature, the system was washed with saturated aqueous sodium sulfite solution and extracted with dichloromethane. The organic phase was heated and rotary evaporated under vacuum, and then purified by column chromatography using a dichloromethane / petroleum ether mixture as the eluent to obtain 1.03 g of the target product BN-51 as a red solid, with a yield of 71%.

[0189] Synthesis route and reaction steps description of general formula II-3

[0190]

[0191]

[0192] First, using carbazole-based raw materials Ai (A1 - A24) as substrates, intermediate IV-d-n (n = 1 - 416) was synthesized by the method reported in the previous patent. Then, sulfur was introduced into the compound under the catalysis of iodine to obtain the final product BN-n (n = 1 - 416).

[0193] In the first step, 20.0 mmol of raw material IV-a-n (n = 1 - 416), 20.0 mmol of raw material Ai (A1 - A24), and 8.15 g of cesium carbonate (25.0 mmol) were added to 150 mL of anhydrous DMF (N,N-dimethylformamide). The reaction system was stirred at 160 °C for 12 hours. After the reaction system was cooled to room temperature, the reaction mixture was extracted with dichloromethane and water. The organic phase was heated and evaporated to dryness under vacuum, and then purified by column chromatography to obtain intermediate IV-b-n (n = 1 - 416).

[0194] In the second step, 15 mmol of intermediate IV-b-n (n = 1 - 416), 17.0 mmol of raw material Ai (A1 - A24), and 6.52 g of cesium carbonate (20.0 mmol) were added to 150 mL of anhydrous DMF (N,N-dimethylformamide). The reaction system was stirred at 160 °C for 18 hours, then cooled to room temperature and poured into ice water (2 L). The white solid was filtered out, dried in vacuo, and then further purified by column chromatography using a mixed eluent of dichloromethane / petroleum ether to obtain intermediate IV-c-n (n = 1 - 416).

[0195] In the third step, under the protection of a nitrogen atmosphere, 17.2 mL of a pentane solution of tert-butyllithium (22.4 mmol) was slowly added to 100 mL of a tert-butylbenzene solution containing 11.2 mmol of intermediate IV-c-n (n = 1 - 416) at -30 °C. The temperature was slowly raised to 60 °C, and after stirring for 2 hours, the pentane was removed under vacuum. Then, it was cooled to -30 °C, and 2.2 mL of boron tribromide (22.4 mmol) was added. The reaction mixture was stirred at room temperature for 1 hour. Then, 3.7 mL of N,N-diisopropylethylamine (22.4 mmol) was added at 0 °C, and then the reaction mixture was heated to 130 °C and stirred for another 5 hours, and then cooled to room temperature. 5 mL of methanol was added to the reaction mixture to quench the residual boron tribromide. The reaction system was concentrated under vacuum and purified by column chromatography using a mixture of dichloromethane / petroleum ether as the eluent to obtain the precursor IV-d-n (n = 1 - 416).

[0196] Step 4: Dissolve 1.5 mmol of precursor IV-d-n (n = 1 - 416), 50 mg of iodine (0.2 mmol), and 384 mg of sulfur (12.0 mmol) in 10 mL of dry o-dichlorobenzene. Bubble the mixture with nitrogen for 5 minutes, then heat the system to 190 °C and stir for 72 hours. After cooling to room temperature, wash the system with saturated aqueous sodium sulfite solution, extract with dichloromethane, heat and spin-dry the organic phase under vacuum, and then purify by column chromatography using a mixed eluent of dichloromethane / petroleum ether to obtain the target product BN-n (n = 1 - 416).

[0197] Taking compound BN-353 as an example to illustrate the specific details of the synthesis example experiment:

[0198] Step 1: Add 3.86 g of raw material IV-a-353 (20.0 mmol of 1-bromo-2,6-difluorobenzene), 8.15 g of raw material A16 (20.0 mmol), and 8.15 g of cesium carbonate (25.0 mmol) to 150 mL of anhydrous DMF (N,N-dimethylformamide). Stir the reaction system at 160 °C for 12 hours. After the reaction system cools to room temperature, extract the reaction mixture with dichloromethane and water, heat and spin-dry the organic phase under vacuum, and then purify by column chromatography to obtain 10.45 g of intermediate IV-b-353, which is a white solid with a yield of 90%.

[0199] Step 2: Add 8.71 g of intermediate IV-b-353 (15 mmol), 5.60 g of raw material A11 (17.0 mmol), and 6.52 g of cesium carbonate (20.0 mmol) to 150 mL of anhydrous DMF (N,N-dimethylformamide). Stir the reaction system at 160 °C for 18 hours, then cool to room temperature and pour it into ice water (2 L). Filter out the white solid, dry it in vacuo, and then further purify by column chromatography using a mixed eluent of dichloromethane / petroleum ether to obtain 11.61 g of intermediate IV-c-353, which is a white solid with a yield of 87%.

[0200] Step 3: Under the protection of nitrogen atmosphere, 17.2 mL of a pentane solution of tert-butyllithium (22.4 mmol) was slowly added to 100 mL of a tert-butylbenzene solution containing 9.97 g of intermediate IV-c-353 (11.2 mmol) at -30 °C. The temperature was slowly raised to 60 °C, and after stirring for 2 hours, pentane was removed under vacuum. Then, it was cooled to -30 °C, 2.2 mL of boron tribromide (22.4 mmol) was added, and the reaction mixture was stirred at room temperature for 1 hour. Then, 3.7 mL of N,N-diisopropylethylamine (22.4 mmol) was added at 0 °C, and then the reaction mixture was heated to 130 °C and stirred for another 5 hours, and then cooled to room temperature. 5 mL of methanol was added to the reaction mixture to quench the residual boron tribromide. The reaction system was concentrated under vacuum and purified by column chromatography using a mixture of dichloromethane / petroleum ether as the eluent to obtain 5.05 g of intermediate IV-d-353 as a yellow solid with a yield of 55%.

[0201] Step 4: 1.23 g of precursor IV-d-353 (1.5 mmol), 50 mg of iodine (0.2 mmol), and 384 mg of sulfur (12.0 mmol) were dissolved in 10 mL of dry o-dichlorobenzene. The mixture was bubbled with nitrogen for 5 minutes, and then the system was heated to 190 °C and stirred for 72 hours. After cooling to room temperature, the system was washed with a saturated aqueous solution of sodium sulfite and extracted with dichloromethane. The organic phase was heated and spun dry under vacuum, and then purified by column chromatography using a mixture of dichloromethane / petroleum ether as the eluent to obtain 831 mg of the target product BN-353 as a blue solid with a yield of 63%.

[0202] The products were characterized. The test instrument used for elemental analysis was VarioMicro Cube from Agilent Technologies, USA, and the tested elemental species were C, H, N, and S. The instrument used for mass spectrometry testing was Thermo Fisher TSQEndura ultra-high performance liquid chromatography tandem triple quadrupole mass spectrometer, and the relevant data are shown in Table 1.

[0203] Table 1

[0204]

[0205]

[0206]

[0207]

[0208] Examples of electroluminescent devices

[0209] Some representative embodiments of the electroluminescent device are given below. The molecular structures of some materials involved in the device embodiments and the comparative embodiments are as follows:

[0210]

[0211]

[0212] The following are embodiments of the electroluminescent device prepared using the materials of the present invention. The specific device preparation process is as follows:

[0213] Preparation process of the organic electroluminescent device:

[0214] The structure of the device is as shown in Figure 1 where 1 is the ITO anode, 2 is the first hole transport layer, 3 is the second hole transport layer, 4 is the light-emitting layer, 5 is the second electron transport layer, 6 is the first electron transport layer, 7 is the electron injection layer, and 8 is the metal cathode.

[0215] The preparation process is as follows:

[0216] (1) Substrate treatment: The transparent ITO glass is used as the substrate material for preparing the device. First, it is ultrasonically treated with 5% ITO cleaning solution for 30 min, and then ultrasonically washed successively with distilled water (twice), acetone (twice), and isopropanol (twice). Finally, the ITO glass is stored in isopropanol. Before each use, the surface of the ITO glass is carefully wiped with acetone cotton balls and isopropanol cotton balls, dried after being rinsed with isopropanol, and then treated with plasma for 5 min for standby. The preparation of the device is completed by combining the spin coating and vacuum evaporation processes.

[0217] (2) Preparation of the hole injection layer and the hole transport layer: The hole transport layer is prepared by the evaporation process. When the vacuum degree of the vacuum evaporation system reaches below 5×10 -4 Pa, the evaporation starts. The deposition rate is measured by the Sains membrane thickness gauge. The organic hole transport layer is successively deposited on the ITO electrode surface by the vacuum evaporation process. The deposition rate of the hole transport material is

[0218] (3) Preparation of the light-emitting layer: The light-emitting layer is prepared by the evaporation process. When the vacuum degree of the vacuum evaporation system reaches below 5×10 - 4 Pa, the evaporation starts. The deposition rate is measured by the Sains membrane thickness gauge. The light-emitting layer is successively deposited on the hole transport layer by the vacuum evaporation process. The deposition rate of the light-emitting layer material is

[0219] (4) Preparation of the electron transport layer, the electron injection layer, and the metal electrode: The electron transport layer, the electron injection layer, and the metal electrode are prepared by the evaporation process. When the vacuum degree of the vacuum evaporation system reaches below 5×10 -4Evaporation coating starts when the pressure is below Pa, and the deposition rate is measured by a Sains film thickness gauge. Using the vacuum evaporation coating process, an organic electron transport layer, a LiF electron injection layer, and a metal Al electrode are sequentially deposited on the light-emitting layer (for the specific device structure, see the following effect examples). Among them, the deposition rate of the organic material is The deposition rate of LiF is The deposition rate of Al is Device Examples 1 - n (n = 1 - 60)

[0220] In the organic electroluminescent devices in Device Examples 1 - n (n = 1 - 60) (the structure is as Figure 1 shown), HIM-doped HTL-1 is used as the first hole transport layer, HTL-2 is used as the second hole transport layer, RZ-40 is used as the host material in the light-emitting layer, BN-m (m represents the last digit of the code of the light-emitting material used in the device example) is used as the doped light-emitting material (the doping concentration is 1 wt%), TRZ-37 is used as the second electron transport layer, ETL-1 is used as the first electron transport layer, LiF is used as the electron injection layer, and Al is used as the metal cathode. The structure of the organic electroluminescent device in the effect example is [ITO / 15 wt% HIM + 85 wt% HTL-1 (100 nm) / HTL-2 (10 nm) / 99 wt% TRZ-40 + 1 wt% BN-m (30 nm) / TRZ-37 (10 nm) / ETL-1 (30 nm) / LiF (1 nm) / Al (100 nm)].

[0221] The performance data of the device examples are shown in Table 2. The characteristics of the device such as current, voltage, brightness, and emission spectrum are synchronously tested using a Photo Research PR 655 spectral scanning luminance meter and a Keithley K 2400 digital source meter system. The performance test of the device is carried out at room temperature and in an ambient atmosphere. The external quantum efficiency (EQE) of the device is calculated from the current density, brightness, and electroluminescence spectrum in combination with the visibility function under the condition that the emission is Lambertian distribution (the same hereinafter). The device lifetime (T50, hours) in Table 2 refers to the time required when the initial brightness of the device is 1000 cd / m 2 , when the brightness of the device drops to 50% of the initial brightness (that is, when the device brightness drops to 500 cd / m 2 ).

[0222] Comparative Device Examples D1 - n (n = 1 - 21)

[0223] In the organic electroluminescent devices in Comparative Device Examples 1 - n (n = 1 - 21) (the structure is as Figure 1In the structure shown in the figure, HIM-doped HTL-1 is used as the first hole transport layer, HTL-2 is used as the second hole transport layer, TRZ-40 is used as the host material in the light-emitting layer, R-m (m represents the last digit of the light-emitting material code used in the comparative device example) is used as the doped light-emitting material (doping concentration is 1 wt%), TRZ-37 is used as the second electron transport layer, ETL-1 is used as the first electron transport layer, LiF is used as the electron injection layer, and Al is used as the metal cathode. The structure of the organic electroluminescent device in the effect example is [ITO / 15 wt% HIM + 85 wt% HTL-1 (100 nm) / HTL-2 (10 nm) / 99 wt% TRZ-40 + 1 wt% R-m (30 nm) / TRZ-37 (10 nm) / ETL-1 (30 nm) LiF (1 nm) / Al (100 nm)].

[0224] The performance data of the comparative device example are shown in Table D1. In Table D1, the device lifetime (T50, hours) refers to the time when the initial brightness of the device is 1000 cd / m 2 , when the brightness of the device drops to 50% of the initial brightness (i.e., when the device brightness drops to 500 cd / m 2 ).

[0225] Figure 2 is the electroluminescence spectrum of the device using the compound BN-21. Its emission peak is located at 604 nm, and the full width at half maximum is 59 nm.

[0226] Figure 3 is the electroluminescence spectrum of the device using the compound BN-31. Its emission peak is located at 624 nm, and the full width at half maximum is 58 nm.

[0227] Table 2

[0228]

[0229]

[0230] Table D1

[0231]

[0232]

[0233] Device Example 2-n (n = 1 - 60)

[0234] In the organic electroluminescent device in Device Example 2-n (n = 1 - 60) (the structure is as Figure 1As shown in [description], HTL-1 doped with HIM is used as the first hole transport layer, HTL-2 is used as the second hole transport layer, TRZ-40-+IrPPy-O is used as the host material in the light-emitting layer, BN-m (m represents the last digit of the code of the light-emitting material used in the device embodiment) is used as the doped light-emitting material (doping concentration is 1 wt%), TRZ-37 is used as the second electron transport layer, ETL-1 is used as the first electron transport layer, LiF is used as the electron injection layer, and Al is used as the metal cathode. The structure of the organic electroluminescent device in the effectiveness embodiment is [ITO / 15 wt% HIM + 85 wt% HTL-1 (100 nm) / HTL-2 (10 nm) / 90 wt% TRZ-40 + 9 wt% IrPPy-O + 1 wt% BN-m (30 nm) / TRZ-37 (10 nm) / ETL-1 (30 nm) LiF (1 nm) / Al (100 nm)].

[0235] The performance data of the device embodiment are shown in Table 3. The device lifetime (T50, hours) in Table 3 refers to the time when the initial brightness of the device is 1000 cd / m 2 , when the brightness of the device drops to 50% of the initial brightness (i.e., when the device brightness drops to 500 cd / m 2 ).

[0236] Comparative device embodiment D2-n (n = 1 - 21)

[0237] In the organic electroluminescent device in the comparative device embodiment D2-n (n = 1 - 21) (the structure is as Figure 1 shown), HTL-1 doped with HIM is used as the first hole transport layer, HTL-2 is used as the second hole transport layer, TRZ-40 + IrPPy-O is used as the host material in the light-emitting layer, R-m (m represents the last digit of the code of the light-emitting material used in the comparative device embodiment) is used as the doped light-emitting material (doping concentration is 1 wt%), TRZ-37 is used as the second electron transport layer, ETL-1 is used as the first electron transport layer, LiF is used as the electron injection layer, and Al is used as the metal cathode. The structure of the organic electroluminescent device in the effectiveness embodiment is [ITO / 15 wt% HIM + 85 wt% HTL-1 (100 nm) / HTL-2 (10 nm) / 90 wt% TRZ-40 + 9 wt% IrPPy-O + 1 wt% R-m (30 nm) / TRZ-37 (10 nm) / ETL-1 (30 nm) LiF (1 nm) / Al (100 nm)].

[0238] The performance data of the comparative device embodiment are shown in Table D3. The device lifetime (T50, hours) in Table D3 refers to the time when the initial brightness of the device is 1000 cd / m 2, when the brightness of the device drops to 50% of the initial brightness (i.e., when the device brightness drops to 500 cd / m 2 ), the time required.

[0239] Table 3

[0240]

[0241]

[0242]

[0243] Table D3

[0244]

[0245] Device Example 3-n (n = 1 - 31)

[0246] In the organic electroluminescent device in Device Example 3-n (n = 1 - 31) (the structure is as Figure 1 shown), HIM-doped HTL-1 is used as the first hole transport layer, HTL-2 is used as the second hole transport layer, RZ-40 is used as the host material in the light-emitting layer, BN-m (m represents the last digit of the light-emitting material code used in the device example) is used as the doped light-emitting material (doping concentration is 1 wt%), TRZ-37 is used as the second electron transport layer, ETL-1 is used as the first electron transport layer, LiF is used as the electron injection layer, and Al is used as the metal cathode. The structure of the organic electroluminescent device in the Effect Example is [ITO / 15 wt% HIM + 85 wt% HTL-1 (100 nm) / HTL-2 (10 nm) / 99 wt% TRZ-40 + 1 wt% BN-m (30 nm) / ETL-1 (10 nm) / TRZ-37 (10 nm) / ETL-1 (30 nm) / LiF (1 nm) / Al (100 nm)].

[0247] The performance data of the device examples are shown in Table 4. The device lifetime (T50, hours) in Table 4 refers to when the initial brightness of the device is 600 cd / m 2 , when the brightness of the device drops to 50% of the initial brightness (i.e., when the device brightness drops to 300 cd / m 2 ), the time required.

[0248] Comparative Device Example D3-1

[0249] In the organic electroluminescent device in Device Example D3-1 (the structure is as Figure 1In the figure (not shown), HIM-doped HTL-1 is used as the first hole transport layer, HTL-2 is used as the second hole transport layer, RZ-40 is used as the host material in the light-emitting layer, R-17 is used as the doped luminescent material (doping concentration is 1 wt%), TRZ-37 is used as the second electron transport layer, ETL-1 is used as the first electron transport layer, LiF is used as the electron injection layer, and Al is used as the metal cathode. The structure of the organic electroluminescent device in the effect example is [ITO / 15 wt% HIM + 85 wt% HTL-1 (100 nm) / HTL-2 (10 nm) / 99 wt% TRZ-40 + 1 wt% R-17 (30 nm) / TRZ-37 (10 nm) / ETL-1 (30 nm) / LiF (1 nm) / Al (100 nm)].

[0250] The performance data of the device example are shown in Table D4. The device lifetime (T50, hours) in Table D4 refers to the time when the initial brightness of the device is 600 cd / m 2 , and when the brightness of the device drops to 50% of the initial brightness (i.e., when the device brightness drops to 300 cd / m 2 ).

[0251] Figure 4 The electroluminescence spectrum of the device using the compound BN-313 is shown. Its emission peak is located at 680 nm, and the full width at half maximum is 62 nm.

[0252] Table 4

[0253]

[0254]

[0255] Table D4

[0256]

[0257] Device example 4-n (n = 1 - 31)

[0258] In the organic electroluminescent device in device example 4-n (n = 1 - 31) (the structure is as Figure 1As shown, HIM-doped HTL-1 is used as the first hole transport layer, HTL-2 is used as the second hole transport layer, TRZ-40 + IrPPy-R is used as the host material in the light-emitting layer, BN-m (where m represents the last digit of the light-emitting material code used in the device embodiment) is used as the doped light-emitting material (doping concentration is 1 wt%), TRZ-37 is used as the second electron transport layer, ETL-1 is used as the first electron transport layer, LiF is used as the electron injection layer, and Al is used as the metal cathode. The structure of the organic electroluminescent device in the effect embodiment is [ITO / 15 wt% HIM + 85 wt% HTL-1 (100 nm) / HTL-2 (10 nm) / 90 wt% TRZ-40 + 9 wt% IrPPy-R + 1 wt% BN-m (30 nm) / TRZ-37 (10 nm) / ETL-1 (30 nm) LiF (1 nm) / Al (100 nm)].

[0259] The performance data of the device embodiment are shown in Table 5. In Table 5, the device lifetime (T50, hours) refers to the time required when the initial brightness of the device is 600 cd / m 2 , when the brightness of the device drops to 50% of the initial brightness (i.e., when the device brightness drops to 300 cd / m 2 .

[0260] Comparative device embodiment D4-1

[0261] In the organic electroluminescent device of device embodiment D4-1 (the structure is as Figure 1 shown), HIM-doped HTL-1 is used as the first hole transport layer, HTL-2 is used as the second hole transport layer, TRZ-40 + IrPPy-R is used as the host material in the light-emitting layer, R-17 is used as the doped light-emitting material (doping concentration is 1 wt%), TRZ-37 is used as the second electron transport layer, ETL-1 is used as the first electron transport layer, LiF is used as the electron injection layer, and Al is used as the metal cathode. The structure of the organic electroluminescent device in the effect embodiment is [ITO / 15 wt% HIM + 85 wt% HTL-1 (100 nm) / HTL-2 (10 nm) / 90 wt% TRZ-40 + 9 wt% IrPPy-R + 1 wt% R-17 (30 nm) / TRZ-37 (10 nm) / ETL-1 (30 nm) LiF (1 nm) / Al (100 nm)].

[0262] The performance data of the device embodiment are shown in Table D5. In Table D5, the device lifetime (T50, hours) refers to the time required when the initial brightness of the device is 600 cd / m 2 , when the brightness of the device drops to 50% of the initial brightness (i.e., when the device brightness drops to 300 cd / m 2The time required (when).

[0263] Table 5

[0264]

[0265] Table D5

[0266]

[0267] The applicant declares that the present invention illustrates the sulfur-containing boron nitride compound and its application of the present invention through the above embodiments, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvement to the present invention, the equivalent substitution of the raw materials selected for the present invention, the addition of auxiliary components, the selection of specific methods, etc., all fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A sulfur-containing boron nitride compound, characterized in that, The sulfur-containing boron nitride compound has a structure represented by the following formula I or formula II: R 1 、R 2 、R 3 、R 4 、R 5 、R 5 、R 7 and R 8 are independently selected from H, deuterium, C1-C20 alkyl, C1-C20 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, C6-C18 aryl substituted with one or more R a , 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted with one or more R a , diphenylamino, or diphenylamino substituted with one or more R a ; R a Each occurrence is independently deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C12 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted with one or more R b groups, 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted with one or more R b groups, diphenylamino, or diphenylamino substituted with one or more R b groups; R b each occurrence independently is deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted with one or more R c substituents, 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted with one or more R c substituents, diphenylamino, or diphenylamino substituted with one or more R c substituents; R c Each occurrence is independently deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted with one or more R d substituents, 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted with one or more R d substituents, diphenylamino, or diphenylamino substituted with one or more R d substituents; R d Each occurrence is independently deuterium, fluorine, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, or C6-C14 aryl substituted with one or more R e substituents; R e Each occurrence is independently deuterium, fluorine, a C1-C12 alkyl group, a C1-C12 alkoxy group, a C3-C10 cycloalkyl group, or a C6-C14 aryl group; R 1 、R 2 、R 3 and R 4 exist independently or R 1 、R 2 、R 3 and R 4 form a ring with the adjacent aromatic ring; R 5 、R 5 、R 7 and R 8 exist independently or R 5 、R 5 、R 7 and R 8 form a ring with the adjacent aromatic ring; R 31 and R 32 are independently selected from H, deuterium, C1-C20 alkyl, C1-C20 alkoxy, C3-C10 cycloalkyl, C6-C18 aryl, C6-C18 aryl substituted with one or more R f groups, 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted with one or more R f groups, diphenylamino, or diphenylamino substituted with one or more R f groups; R f Each occurrence is independently deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C12 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted with one or more R g groups, 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted with one or more R b groups, diphenylamino, or diphenylamino substituted with one or more R g groups; R g Each occurrence is independently deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted with one or more R c substituted C6-C14 aryl, 5- to 18-membered heteroaryl; R 31 It can exist independently or form a ring with R; R is a C6-C18 aryl group, a C6-C18 aryl group substituted by one or more Rs h a 5- to 18-membered heteroaryl group, a 5- to 18-membered heteroaryl group substituted by one or more Rs h a diphenylamino group, or a diphenylamino group substituted by one or more Rs h ; R h Each occurrence is independently deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C12 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted with one or more R i groups, 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted with one or more R i groups, diphenylamino, or diphenylamino substituted with one or more R i groups; R i Each occurrence is independently deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted with one or more R c substituted C6-C14 aryl, 5- to 18-membered heteroaryl; E is S, where the wavy line represents the connection site of the group. When E is R 6 is the same as R 7 and R 5 is the same as R 8 ; R 21 、R 22 、R 23 、R 24 、R 25 and R 26 are independently H, D (deuterium), F, CN, C1-C20 alkyl, C1-C20 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, C6-C18 aryl substituted with one or more R m substituents, 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted with one or more R m substituents, diphenylamino, or diphenylamino substituted with one or more R m substituents; R m Each occurrence is independently deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C12 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted by one or more R n groups, 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted by one or more R n groups, diphenylamino, or diphenylamino substituted by one or more R n groups; R n Each occurrence is independently deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, C6-C14 aryl substituted with one or more R c groups, 5- to 18-membered heteroaryl; R 21 、R 22 、R 23 、R 24 exist independently or at least two of them are adjacent to each other to form a ring (for example, R 21 and R 22 form a ring with each other, or R 22 and R 23 form a ring with each other, or R 23 and R 24 form a ring with each other), R 25 and R 26 exist independently or form a ring with each other; The alkyl, alkoxy, cycloalkyl, aryl, and heteroaryl are optionally substituted with one or more substituents selected from the following: halogen, -CN, C1-C12 alkyl, C1-C12 alkoxy, C1-C12 haloalkyl, C3-C10 cycloalkyl, C6-C14 aryl, and 5- to 18-membered heteroaryl.

2. The sulfur-containing boron nitride compound according to claim 1, characterized in that, Said R 1 , R 2 , R 3 , R 4 , R 5 , R 5 , R 7 and R 8 are independently H, D (deuterium), C1-C12 alkyl, C1-C 12 alkoxy, C3-C 10 cycloalkyl, phenyl, aryl substituted by at least one C1-C 12 alkyl, aryl substituted by at least one C1-C 12 alkoxy, phenyl-C1-C 12 alkyl, diphenylamino, diphenylamino substituted by at least one C1-C 12 alkyl, carbazolyl, carbazolyl substituted by at least one C1-C 12 alkyl; Preferably, the R a is independently deuterium, fluorine, C1-C 12 alkyl, C1-C 12 alkoxy, C3-C 10 cycloalkyl, phenyl substituted by at least one C1-C 12 alkyl, phenyl substituted by at least one C1-C 12 alkoxy, phenyl-C1-C 12 alkyl, diphenylamino, diphenylamino substituted by at least one C1-C 12 alkyl, carbazolyl, carbazolyl substituted by at least one C1-C 12 alkyl each time it appears; Preferably, the R b is, each time it appears, independently deuterium, fluorine, C1-C 12 alkyl, C1-C 12 alkoxy, C3-C 10 cycloalkyl, phenyl substituted by at least one C1-C 12 alkyl, phenyl substituted by at least one C1-C 12 alkoxy, phenyl-C1-C 12 alkyl, diphenylamino, diphenylamino substituted by at least one C1-C 12 alkyl, carbazolyl, carbazolyl substituted by at least one C1-C 12 alkyl; Preferably, said R c is independently deuterium, fluorine, C1-C 12 alkyl, C1-C 12 alkoxy, C3-C 10 cycloalkyl, phenyl substituted by at least one C1-C 12 alkyl, phenyl substituted by at least one C1-C 12 alkoxy, phenyl-C1-C 12 alkyl, diphenylamino, diphenylamino substituted by at least one C1-C 12 alkyl, carbazolyl, carbazolyl substituted by at least one C1-C 12 alkyl; Preferably, the R d is independently deuterium, fluorine, C1-C 12 alkyl, C1-C 12 alkoxy, C3-C 10 cycloalkyl, phenyl substituted by at least one C1-C 12 alkyl, phenyl substituted by at least one C1-C 12 alkoxy, carbazolyl, carbazolyl substituted by at least one C1-C 12 alkyl; Preferably, the R 1 , R 2 , R 3 , R 4 , R 5 , R 5 , R 7 and R 8 are independently H, deuterium, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, hexyl, octyl, decyl, methoxy, ethoxy, butoxy, hexyloxy, cyclohexyl, adamantyl, phenyl, 2-methyl-phenyl, 4-methyl-phenyl, 4-ethyl-phenyl, 4-propyl-phenyl, 4-isopropylphenyl, 4-n-butylphenyl, wherein the wavy line represents the connection site of the group; Preferably, the R 1 , R 2 , R 3 , R 4 , R 5 , R 5 , R 7 and R 8 are independently H, methyl, phenyl, 2-methyl-phenyl, where the wavy line represents the connection site of the group; Preferably, the R 1 , R 2 , R 3 , R 4 , R 5 , R 5 , R 7 and R 8 are the same and are selected from any one of H, methyl, phenyl, 2-methyl-phenyl, ; wherein R j is H, methyl, isopropyl, tert-butyl or Preferably, R 1 , R 2 , R 3 and R 4 at least one of which forms any one of the following ring structures with the connected aromatic ring: Wherein the key where the * is located is a bond shared with the aromatic ring; Preferably, R 5 , R 5 , R 7 and R 8 at least one of them forms any one of the following ring structures with the connected aromatic ring: Among them, the key where the * is located is the bond shared with the aromatic ring; Preferably, the R 31 and R 32 are independently selected from H, deuterium, C1-C6 alkyl, C6-C18 aryl or C5-C18 heteroaryl; Preferably, R is selected from C6-C18 aryl or 5- to 24-membered heteroaryl; Preferably, the R is selected from phenyl, biphenyl, phenyl-substituted biphenyl, wherein the wavy line represents the connection site of the group; Preferably, E is S, wherein the wavy line represents the attachment site of the group.

3. The sulfur-containing boron nitride compound according to claim 1 or 2, characterized in that, The sulfur-containing boron nitride compound is any one of the following compounds:

4. An organic electroluminescent composition, characterized in that, It includes the boron nitride compound as described in any one of claims 1-3 as a doping material and a host material; Preferably, the host material is a material having electron-transporting ability and / or hole-transporting ability and whose triplet excited state energy is equal to or higher than the triplet excited state energy of the doping material.

5. The organic electroluminescent composition according to claim 4, wherein The doping material in the organic electroluminescent composition is any one of the boron nitride compounds described in any one of claims 1-3; the host material is any one of the compounds represented by formula Trz1-A, Trz2-A, or Trz3-A; Z is N or CH; wherein R z1 to R z10 independently is hydrogen, deuterium, F, CN, C1-C8 alkyl, C1-C8 alkoxy, C6-C 30 aryl, R za substituted C6-C 30 aryl, C6-C30 heteroaryl or R za group-substituted C6-C 30 heteroaryl; R za is a C1-C8 alkyl group, a C1-C8 alkoxy group, a C6-C 24 aryl group or a C6-C 24 heteroaryl group; R z9 or R z10 forms a ring independently or with an aromatic ring connected thereto; Preferably, the weight percentage content of the doping material in the organic electroluminescent composition is 0.3wt-30.0wt%, and the content of the host material is 99.7wt-70.0wt% by weight percentage; Preferably, the doping material in the organic electroluminescent composition is any one of the compounds BN-1 to BN-416, and the host material is composed of any one of the compounds represented by formula Trz1-A, Trz2-A, or Trz3-A; Preferably, Trz1-A, Trz2-A, or Trz3-A are the specific compounds shown as TRZ-1 to TRZ-48; Preferably, the doping material in the organic electroluminescent composition is any one of the compounds described in claims 1-3, and the host material is composed of any one of the compounds represented by formula TRZ-1 to TRZ-48; Preferably, the doping material in the organic electroluminescent composition is any one of the compounds BN-1 to BN-416, and the host material is composed of any one of the compounds represented by formula TRZ-1 to TRZ-48; Preferably, the doping material in the organic electroluminescent composition is any one of the compounds described in claims 1-3, and the host material is composed of any one of the compounds represented by formula TTrz1-A, Trz2-A, or Trz3-A and a phosphorescent compound containing metal Ir represented by formula Ir-1 and formula Ir-2; preferably, in the host material, the weight ratio between the compound represented by formula Trz1-A, Trz2-A, or Trz3-A and the phosphorescent compound containing metal Ir is 5:1 to 20:1; R ri independently hydrogen, deuterium, a C1-C18 alkyl group or a C6-C18 aryl group, where i is an integer from 1 to 22, and where the dashed line represents that two of the four bonds included are double bonds spaced apart; R ri Any one of the groups may form a ring with the aromatic ring or aromatic heterocycle to which it is attached; Preferably, the phosphorescent compound containing metal Ir is any one of the following compounds: Preferably, the dopant material in the organic electroluminescent composition is any one of the compounds represented by Formulas BN-1 to BN-416, and the host material is composed of any one of the compounds represented by Formulas Trz1-A, Trz2-A or Trz3-A and a phosphorescent compound containing metal Ir represented by Formulas Ir-1 and Ir-2; preferably, in the host material, the weight ratio between the compound represented by Formulas Trz1-A, Trz2-A or Trz3-A and the phosphorescent compound containing metal Ir is 5:1 to 20:1; Preferably, the dopant material in the organic electroluminescent composition is any one of the compounds represented by Formulas BN-1 to BN-416, and the host material is composed of any one of the compounds represented by Formulas TRZ-1 to TRZ-48 and a phosphorescent compound containing metal Ir represented by Formulas Ir-1 and Ir-2; preferably, in the host material, the weight ratio between the compound represented by Formulas TRZ-1 to TRZ-48 and the phosphorescent compound containing metal Ir is 5:1 to 20:

1.

6. An organic electroluminescent material, characterized in that, The organic electroluminescent material includes the boron nitride compound according to any one of Claims 1-3 or the organic electroluminescent composition according to Claim 4 or 5.

7. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes an anode and a cathode, and an organic thin film layer disposed between the anode and the cathode, and the organic thin film layer includes the boron nitride compound according to any one of Claims 1-3 or the organic electroluminescent composition according to Claim 4 or 5.

8. The organic electroluminescent device according to claim 7, characterized in that, The organic thin film layer includes a light-emitting layer, an optional hole injection layer, an optional hole transport layer, an optional electron transport layer, and an optional electron injection layer, wherein at least one of the light-emitting layer, the electron injection layer, the electron transport layer, the hole transport layer, and the hole injection layer includes the boron nitride compound according to any one of Claims 1-3 or the organic electroluminescent composition according to Claim 4 or 5.

9. The organic electroluminescent device according to claim 7 or 8, characterized in that, The material of the light-emitting layer in the organic electroluminescent device includes the boron nitride compound according to any one of Claims 1-3 or the organic electroluminescent composition according to Claim 4 or 5; Preferably, the organic electroluminescent device further includes an optional hole blocking layer, an optional electron blocking layer, and an optional capping layer.

10. Use of the organic electroluminescent device according to any one of Claims 7-9 in an organic electroluminescent display or an organic electroluminescent lighting source.

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