A polycyclic compound containing triphenylsilicon and polyalkyl substituents and an organic electroluminescence device comprising the same

Abstract

The application belongs to the technical field of OLED, and provides a polycyclic compound containing triphenylsilicon and a multi-alkyl substituent and an organic electroluminescent device comprising the same. The structural general formula of the polycyclic compound is shown as formula I. By introducing a more electronegative benzofuran group on the cyclic structure composed of nitrogen atoms and boron atoms, and simultaneously introducing triphenylsilicon at the para position of boron, the synergistic effect of benzofuran and triphenylsilicon can significantly enhance the multiple resonance of the light-emitting core and reduce the vibration relaxation. Therefore, by simultaneously using benzofuran and triphenylsilicon, the problems of increased vibration relaxation and broadened spectrum caused by the introduction of the multi-alkyl substituent are significantly improved, the material luminous efficiency is significantly improved, the color purity is improved, thereby meeting the demand of the BT.2020 wide color gamut display standard for the light-emitting spectrum.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of OLED, and specifically comprises a polycyclic compound containing triphenylsilicon and multi-alkyl substituents and an organic electroluminescent device comprising the same. BACKGROUND

[0002] In the current OLED display field, the problems of low efficiency and short service life of blue light-emitting devices are still the key bottlenecks restricting the development of this field. The mainstream OLED blue light technology currently still uses fluorescent light-emitting materials as host materials (BH) and dopant materials (BD). In the light-emitting process, the dopant material needs to obtain energy from the host material through the host-guest energy transfer mechanism. This process mainly depends on two forms of Förster energy transfer and Dexter energy transfer. Among them, Dexter energy transfer is easy to generate long-lifetime triplet excitons in the working process of the dopant material, and long-time excitation will cause material decomposition, so the occurrence of this energy transfer process should be inhibited as much as possible.

[0003] Since the rate constant of Dexter energy transfer is closely related to the intermolecular distance between the host material and the dopant material, increasing the intermolecular distance between the two materials can significantly reduce the occurrence probability. For this reason, a certain number of alkyl structures are introduced into the existing dopant materials to increase the intermolecular distance. However, too many alkyl structures will significantly enhance the vibration relaxation of the material in the excited state, leading to an increase in the spectral half-width, thereby reducing the light-emitting efficiency. Moreover, the emission half-width of the currently developed blue light-emitting materials is difficult to fully meet the requirements of the BT.2020 wide color gamut standard, and after introducing too many alkyl structures, this problem will be even more serious.

[0004] Therefore, while inhibiting Dexter energy transfer as much as possible, how to reduce vibration relaxation to maintain high light-emitting efficiency has become a core problem that needs to be solved in the development of dopant materials. SUMMARY

[0005] In view of this, the present application provides a polycyclic compound containing triphenylsilicon and multi-alkyl substituents and an organic electroluminescent device comprising the same.

[0006] To achieve the above-mentioned application purposes, the present application adopts the following technical solutions:

[0007] The first aspect of the present application provides a polycyclic compound containing triphenylsilicon and multi-alkyl substituents, and the structure general formula of the polycyclic compound is shown as formula I:

[0008] I;

[0009] wherein R1, R2 are the same or different, each independently represents any one of hydrogen, deuterium, halogen, a substituted or unsubstituted alkyl group having a carbon number of C1 to C30, a substituted or unsubstituted cycloalkyl group having a carbon number of C3 to C30, a substituted or unsubstituted aryl group having a carbon number of C6 to C60, a substituted or unsubstituted heteroaryl group having a carbon number of C5 to C60, a substituted or unsubstituted fused ring aryl group having a carbon number of C6 to C60, a substituted or unsubstituted hetero-fused ring aryl group having a carbon number of C5 to C60, wherein two or more R1, R2 can be connected to each other to form an aliphatic ring, an aromatic ring, or a fused ring;

[0010] R each occurrence is independently represents any one of a substituted or unsubstituted aryl group having a carbon number of C6 to C60, a substituted or unsubstituted heteroaryl group having a carbon number of C5 to C60, a substituted or unsubstituted fused ring aryl group having a carbon number of C6 to C60, a substituted or unsubstituted hetero-fused ring aryl group having a carbon number of C5 to C60;

[0011] m, n each independently represents 0, 1, 2, 3, or 4, preferably 0, 1, or 2;

[0012] When R1, R2, R contains a substituent, the substituent is selected from an alkyl group having a carbon number of C1 to C10 or an aryl group having a carbon number of C6 to C20; two or more of the substituents can be connected to each other to form an aliphatic ring;

[0013] The polycyclic compound contains at least

[0014] 5 tert-butyl groups; or

[0015] 3 tert-butyl groups and 1 ring structure formed by connecting any two adjacent tert-butyl groups to each other;

[0016] Any one hydrogen in Formula I can be substituted by deuterium or an alkyl group.

[0017] It should be first noted that the following is an explanation of the substitution of hydrogen in the structure by tert-butyl groups and ring formation:

[0018] The substitution of any at least one hydrogen by a tert-butyl group means that the hydrogen in the structure can be substituted by one or more tert-butyl groups in the following manner. When the number of substituted tert-butyl groups is more than one, and there are two adjacent tert-butyl groups, the two tert-butyl groups can lose two hydrogens and form a ring structure.

[0019]

[0020] Further, R1, R2each independently represents any one of a substituted or unsubstituted alkyl group having a carbon number of C1-C10, a substituted or unsubstituted aryl group having a carbon number of C6-C30, and two or more of R1, R2may be linked to each other to form an alicyclic ring.

[0021] Further, R each occurrence independently represents a substituted or unsubstituted aryl group having a carbon number of C6-C20.

[0022] Further, R each occurrence independently represents any one of a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group.

[0023] Further, R each occurrence independently represents any one of , , , , , and any hydrogen in the above groups can be replaced with deuterium or an alkyl group.

[0024] Further, the polycyclic compound has a structure represented by any one of the following general formulas:

[0025] I-1, I-2, I-3, I-4;

[0026] R3represents any one of the following structures:

[0027] , , , , , , , ;

[0028] R4represents any one of the following structures:

[0029] , , , , ;

[0030] any hydrogen in the above groups can be replaced with deuterium or a tert-butyl group, and at least one hydrogen in the above groups is replaced with a tert-butyl group, and when the number of replaced hydrogens is more than one, two adjacent tert-butyl groups can be linked to form a ring structure;

[0031] " represents a bond. " represents a bond.

[0032] Further, R3 represents one of the following structures:

[0033] , ,

[0034] , , ;

[0035] and / or

[0036] R4 represents one of the following structures:

[0037] , , , , , .

[0038] Further, R1, R2 each independently represents one of the following structures: , , ;

[0039] When R1 represents a tert-butyl group, two adjacent R1 can be connected to each other to form a ring structure.

[0040] When R2 represents a tert-butyl group, two adjacent R2 can be connected to each other to form a ring structure.

[0041] Further, the polycyclic compound is selected from the following structures:

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068]

[0069]

[0070]

[0071]

[0072]

[0073]

[0074]

[0075]

[0076]

[0077]

[0078]

[0079]

[0080]

[0081]

[0082]

[0083]

[0084]

[0085]

[0086]

[0087]

[0088]

[0089]

[0090]

[0091]

[0092] .

[0093] The second aspect of the present application provides an organic electroluminescent device, comprising an anode, a hole transport zone, a light-emitting layer, an electron transport zone and a cathode which are sequentially arranged on a substrate; wherein the light-emitting layer comprises a host material and a doping material, and the doping material comprises one or more polycyclic compounds as described above.

[0094] Further, the host material is selected from the general structure as shown below:

[0095] II;

[0096] wherein,

[0097] L is selected from a single bond or a phenylene group;

[0098] Ar1 is selected from a phenyl group or a naphthyl group;

[0099] Ar2 represents one of the following groups:

[0100] 、 、 , ;

[0101] Any one of the hydrogens in Formula II can be replaced by deuterium, alkyl or aryl;

[0102] " represents a connecting bond. " represents a connecting bond.

[0103] Further, the host material is selected from the group consisting of structures as shown below:

[0104]

[0105]

[0106]

[0107]

[0108]

[0109]

[0110]

[0111] .

[0112] Further, the content of the host material in the light-emitting layer should be greater than 50wt%, preferably greater than 90wt%.

[0113] Further, the content of the dopant material in the light-emitting layer should be less than 20wt%, preferably less than 5wt%.

[0114] Further, the hole transport zone comprises at least one functional layer for transporting holes, such as a hole transport layer, a light-emitting auxiliary layer, the material used in the hole transport layer, light-emitting auxiliary layer is selected from the group consisting of general structures as shown below:

[0115] H-1;

[0116] wherein each L1independently represents a single bond, phenylene or biphenylene;

[0117] each Ar3independently represents the following group:

[0118] , , , , , , , , ;

[0119] any one of the hydrogens in formula H-1 can be replaced by deuterium, alkyl, aryl;

[0120] " represents a bond. " represents a bond.

[0121] Further, the material used in the hole transport layer is selected from the following structures:

[0122]

[0123]

[0124]

[0125]

[0126]

[0127]

[0128]

[0129]

[0130]

[0131] .

[0132] Further, the electron transport region comprises at least one functional layer for transporting electrons, such as an electron transport layer, a hole blocking layer, and the material used in the electron transport layer, the hole blocking layer is selected from the following general structures:

[0133] H-2;

[0134] wherein L2 is selected from a single bond, phenylene or biphenylene;

[0135] each Ar4 independently represents the following group:

[0136] , , ;

[0137] Ar5 represents the following group:

[0138] , , , , , , , ;

[0139] Any one hydrogen in formula H-2 can be replaced by deuterium, alkyl, aryl;

[0140] " represents a connecting bond. " represents a connecting bond.

[0141] Further, the material used for the electron transport layer is selected from the structures shown below:

[0142]

[0143]

[0144]

[0145]

[0146]

[0147]

[0148]

[0149]

[0150]

[0151]

[0152] .

[0153] The beneficial effects of the present application are as follows:

[0154] The present application provides a polycyclic compound containing triphenylsilicon and polyalkyl substituents, by introducing a more electronegative benzofuran group on the cyclic structure composed of nitrogen and boron atoms, and simultaneously introducing triphenylsilicon at the para position of boron, the synergistic effect of benzofuran and triphenylsilicon can significantly enhance the multiple resonance of the light-emitting core and reduce the vibration relaxation. Therefore, by simultaneous use of benzofuran and triphenylsilicon, the problems of increased vibration relaxation, broadened spectrum, etc. caused by the introduction of polyalkyl substituents are significantly improved, the material luminous efficiency is significantly improved, the color purity is improved, and the demand of BT.2020 wide color gamut display standard for the light-emitting spectrum is met. BRIEF DESCRIPTION OF DRAWINGS

[0155] The specific embodiments of the present application will be further described in detail below with reference to the accompanying drawings.

[0156] Figure 1A schematic diagram of a structure of an organic electroluminescent device containing a compound of the present application; wherein, 1 - substrate, 2 - anode, 3 - hole injection layer, 4 - hole transport layer, 5 - light emitting auxiliary layer, 6 - light emitting layer, 7 - hole blocking layer, 8 - electron transport layer, 9 - electron injection layer, 10 - cathode, 11 - capping layer. DETAILED DESCRIPTION

[0157] In order to more clearly illustrate the present application, the present application will be described with reference to the attached drawings hereinafter. Identical components in the drawings are represented by the same reference numerals. It will be understood by those skilled in the art that the following detailed description of the present application is provided for the purpose of explanation only and is not intended to limit the scope of the present application. The embodiments and comparative examples of the present specification are provided to more completely explain the present specification to those skilled in the art, and the scope of the present application should not be limited only to the embodiments and comparative examples described in detail below.

[0158] The compound of the present application is suitable for use in a light emitting element, a display panel, and an electronic device, and particularly suitable for use in an organic electroluminescent device. The electronic device of the present application is a device comprising at least one layer of an organic compound, and the device can also comprise a layer of an inorganic material or formed entirely of an inorganic material. The electronic device is preferably an organic electroluminescent device (OLED), an organic integrated circuit (O-IC), an organic field effect transistor (O-FET), an organic thin film transistor (O-TFT), an organic light emitting transistor (O-LET), an organic solar cell (O-SC), an organic dye-sensitized solar cell (O-DSSC), an organic optical detector, an organic photoreceptor, an organic field-quenching device (O-FQD), a light emitting electrochemical cell (LEC), an organic laser diode (O-laser), and an organic plasmonic emitter. The electronic device is preferably an organic electroluminescent device (OLED).

[0159] In order to more clearly understand the content of the present application, the light emitting properties of the polycyclic compound containing a triarylamine structure, the preparation method of the compound, and the device will be explained in detail in connection with examples. Various chemical reactions can be applied to the synthesis method of the compound of one embodiment of the present application. However, it should be noted that the synthesis method of the compound of one embodiment of the present application is not limited to the synthesis method described below. Unless otherwise specified, the following synthesis is performed in an anhydrous solvent under a protective gas atmosphere. The solvent and reagent can be purchased from a conventional reagent supplier. The compound of the present application is prepared using a Buchwald-Hartwig coupling reaction, a Suzuki coupling reaction, or a Heck coupling reaction as a representative reaction.

[0160] Synthesis of intermediates

[0161]

[0162] subl (86.5 g), sub2 (39.2 g) and sodium tert-butoxide (10.5 g) were added to toluene (500 ml) followed by the addition of bis(dibenzylideneacetone)palladium (2.7 g) and XantPhos (3.4 g) under nitrogen protection, then the reaction system was heated to reflux and maintained for 10 hours, after cooling to room temperature, quenched with water and separated, the organic phase was filtered and dried over anhydrous sodium sulfate, the solvent was removed by rotary evaporation, the crude product was purified by column chromatography, finally the product sub3 was obtained: 85.8 g, MS (m / z) (M+): 962.

[0163] sub3 (85.8 g), sub4 (28.7 g) and sodium tert-butoxide (7.7 g) were added to toluene (500 ml) followed by the addition of bis(dibenzylideneacetone)palladium (2.0 g) and tri-tert-butylphosphine (0.9 g) under nitrogen protection, then the reaction system was heated to reflux and maintained for 10 hours, after cooling to room temperature, quenched with water and separated, the organic phase was filtered and dried over anhydrous sodium sulfate, the solvent was removed by rotary evaporation, the crude product was purified by column chromatography, finally the product Al was obtained: 79.3 g, MS (m / z) (M+): 1438.

[0164] The intermediates A2-A26 were prepared according to the above procedure, which is not described here again.

[0165] Synthesis Example 1

[0166]

[0167] The system was maintained between -30 and -40 °C under nitrogen protection, n-butyllithium solution (15.40 mL) was slowly added to a solution of compound Al (14.38 g) in tert-butylbenzene (100 mL), then stirred at 60 °C for 6 hours. Then after adding boron tribromide (1.91 mL) at -30 °C, the reaction system was stirred at 60 °C for 6 hours. Finally, N,N-diisopropylethylamine (2.78 mL) was added at 0 °C, and the reaction system was stirred at room temperature for 2 hours. 150 mL of deionized water was added to the reaction system to quench the residual boron tribromide. The mixture was extracted with 200 mL of dichloromethane 3 times, the organic layers were combined, concentrated under vacuum, and purified by column chromatography with dichloromethane / petroleum ether (1:20) mixed eluent, and the crude product was recrystallized with n-heptane, acetone and toluene, finally the product Bl was obtained: 0.87 g, MS (m / z) (M+): 1380.

[0168] 1H NMR (400 MHz, CDC13) δ 8.16 (d, 1H), 7.60 - 7.52 (m, 4H), 7.49 - 7.43 (m, 6H), 7.41 - 7.33 (m, 12H), 7.32 (d, 1H), 7.30 (s, 1H), 7.27 (d, 3H), 7.14 (d, 1H), 7.08 (d, 2H), 7.01 - 6.95 (m, 3H), 1.54-1.49 (m, 12H), 1.35-1.30 (m, 9H), 1.29-1.25 (m, 18H), 0.91-0.87 (m, 36H).

[0169] Synthesis Example 2

[0170]

[0171] The preparation method is the same as that of Synthesis Example 1, except that compound A2 (11.38 g) is used to replace compound Al, and finally product B2 is obtained: 0.74 g, MS (m / z) (M+): 1413.

[0172] 1 H NMR (400 MHz, CDC13) δ 8.60 (d, 1H), 7.64 (dd, 1H), 7.59 - 7.52 (m, 5H), 7.52 - 7.43 (m, 9H), 7.41 - 7.33 (m, 13H), 7.31 (d, 4H), 7.27 (d, 2H), 7.22 (dd, 1H), 7.08 (s, 1H), 7.00 (d, 2H), 1.74 (t, 8H), 1.32 (s, 9H), 1.20 (s, 9H), 1.16-1.10 (m, 18H), 0.99-0.94 (m, 24H).

[0173] Synthesis Example 3

[0174]

[0175] The preparation method is the same as that of Synthesis Example 1, except that compound A3 (14.62 g) is used to replace compound Al, and finally product B3 is obtained: 0.67 g, MS (m / z) (M+): 1391.

[0176] 1H NMR (400 MHz, CDC13) δ 8.16 (d, 1H), 7.59 - 7.51 (m, 6H), 7.45 (ddd, 7H), 7.41 - 7.33 (m, 13H), 7.31 (d, 4H), 7.27 (s, 2H), 7.25 - 7.16 (m, 2H), 7.08 (s, 1H), 7.00 (d, 2H), 6.67 (dd, 1H), 1.61-1.58 (m, 8H), 1.39-1.33 (m, 9H), 1.29 (s, 9H), 1.20-1.16 (m, 18H), 0.92-0.86 (m, 24H).

[0177] Synthesis Example 4

[0178]

[0179] The preparation method is the same as that of Synthesis Example 1, except that compound A4 (13.72 g) is used to replace compound Al, and finally product B4 is obtained: 0.80 g, MS (m / z) (M+): 1344.

[0180] 1 H NMR (400 MHz, CDC13) δ 8.16 (d, 1H), 7.59 - 7.51 (m, 6H), 7.45 (ddd, 7H), 7.41 - 7.33 (m, 13H), 7.31 (d, 4H), 7.27 (s, 2H), 7.25 - 7.16 (m, 2H), 7.08 (s, 1H), 7.00 (d, 2H), 6.67 (dd, 1H), 1.61-1.58 (m, 8H), 1.39-1.33 (m, 9H), 1.29 (s, 9H), 1.20-1.16 (m, 18H), 0.92-0.86 (m, 24H).

[0181] Synthesis Example 5

[0182]

[0183] The preparation method is the same as that of Synthesis Example 1, except that compound A5 (11.30 g) is used to replace compound Al, and finally product B5 is obtained: 0.55 g, MS (m / z) (M+): 1222.

[0184] 1H NMR (400 MHz, CDC13) δ 8.71 (s, 1H), 7.65 (s, 1H), 7.57 (dd, 4H), 7.46 (d, 1H), 7.40 (d, 1H), 7.33 (d, 3H), 7.25 - 7.17 (m, 4H), 6.91 (s, 1H), 6.72 (d, 2H), 6.64 (d, 2H), 6.57 (d, 1H), 6.11 (s, 1H), 1.46 - 1.39 (m, 27H), 1.34 (s, 9H), 0.88 - 0.80 (m, 18H).

[0185] Synthesis Example 6

[0186]

[0187] The preparation method is the same as that of Synthesis Example 1, except that compound A6 (13.07 g) is used to replace compound Al, to finally obtain product B6: 0.60 g, MS (m / z) (M+): 1234.

[0188] 1 H NMR (400 MHz, CDC13) δ = 8.22 (dd, 1H), 7.64 - 7.56 (m, 8H), 7.52 - 7.48 (m, 2H), 7.46 (s, 1H), 7.44 (s, 2H), 7.40 (d, 1H), 7.38 - 7.33 (m, 10H), 7.27 (d, 1H), 7.26 - 7.23 (m, 3H), 7.11 (s, 1H), 7.04 (d, 1H), 7.02 (d, 1H), 1.84 - 1.74 (m, 2H), 1.68 - 1.58 (m, 2H), 1.08 - 1.02 (m, 27H), 0.95-0.89 (m, 12H).

[0189] Synthesis Example 7

[0190]

[0191] The preparation method is the same as that of Synthesis Example 1, except that compound A7 (12.78 g) is used to replace compound Al, to finally obtain product B7: 0.65 g, MS (m / z) (M+): 1207.

[0192] 1H NMR (400 MHz, CDC13) δ 7.57 - 7.51 (m, 3H), 7.45 (td, 7H), 7.37 (q, 10H), 7.35 - 7.29 (m, 5H), 7.27 (s, 3H), 7.20 (d, 1H), 7.10 (dd, 1H), 7.04 (d, 1H), 7.00 (d, 1H), 6.96 (s, 1H), 6.67 (dd, 1H), 1.56-1.51 (m, 12H), 1.35 (s, 9H), 1.27-1.21 (m, 18H), 0.95-0.82 (m, 36H).

[0193] Synthesis Example 8

[0194]

[0195] The preparation method is the same as that of Synthesis Example 1, except that compound A8 (14.40 g) is used to replace compound Al, to finally obtain product B8: 0.74 g, MS (m / z) (M+): 1456.

[0196] 1 H NMR (400 MHz, CDC13) δ 7.57 - 7.51 (m, 3H), 7.45 (td, 7H), 7.37 (q, 10H), 7.35 - 7.29 (m, 5H), 7.27 (s, 3H), 7.20 (d, 1H), 7.10 (dd, 1H), 7.04 (d, 1H), 7.00 (d, 1H), 6.96 (s, 1H), 6.67 (dd, 1H), 1.56-1.51 (m, 12H), 1.35 (s, 9H), 1.27-1.21 (m, 18H), 0.95-0.82 (m, 36H).

[0197] Synthesis Example 9

[0198]

[0199] The preparation method is the same as that of Synthesis Example 1, except that compound A9 (12.74 g) is used to replace compound Al, to finally obtain product B9: 0.75 g, MS (m / z) (M+): 1203.

[0200] 11H NMR (400 MHz, CDC13) δ 7.57 - 7.51 (m, 3H), 7.50 - 7.42 (m, 7H), 7.41 - 7.35 (m, 10H), 7.35 - 7.29 (m, 5H), 7.27 (s, 3H), 7.20 (d, 1H), 7.10 (dd, 1H), 7.04 (d, 1H), 7.00 (d, 1H), 6.96 (s, 1H), 6.67 (dd, 1H), 1.44-1.40 (m, 12H), 1.25 (s, 9H), 1.11-1.06 (m, 18H), 0.91-0.86 (m, 36H).

[0201] Synthesis Example 10

[0202]

[0203] The preparation method is the same as that of Synthesis Example 1, except that compound Al is replaced by compound A10 (14.40 g), to finally obtain product B10: 0.81 g, MS (m / z) (M+): 1477.

[0204] 1H NMR (400 MHz, CDC13) δ 7.57 - 7.51 (m, 3H), 7.50 - 7.42 (m, 7H), 7.41 - 7.35 (m, 10H), 7.35 - 7.29 (m, 5H), 7.27 (s, 3H), 7.20 (d, 1H), 7.10 (dd, 1H), 7.04 (d, 1H), 7.00 (d, 1H), 6.96 (s, 1H), 6.67 (dd, 1H), 1.44-1.40 (m, 12H), 1.25 (s, 9H), 1.11-1.06 (m, 18H), 0.91-0.86 (m, 36H).

[0205] Synthesis Example 11

[0206]

[0207] The preparation method is the same as that of Synthesis Example 1, except that compound Al is replaced by compound A11 (12.56 g), to finally obtain product B11: 0.58 g, MS (m / z) (M+): 1185.

[0208] 1H NMR (400 MHz, CDC13) δ 7.54 (t, 1H), 7.51 (d, 1H), 7.45 (ddd, 7H), 7.41 - 7.33 (m, 12H), 7.27 (d, 2H), 7.25 - 7.17 (m, 4H), 7.14 (d, 1H), 7.12 - 7.06 (m, 2H), 7.04 (d, 1H), 6.97 (dd, 1H), 1.54-1.50 (s, 4H), 1.27-1.22 (m, 18H), 1.18 (s, 9H), 1.15-1.10 (m, 18H), 0.98-0.92 (m, 12H).

[0209] Synthesis Example 12

[0210]

[0211] The preparation method is the same as that of Synthesis Example 1, except that compound A12 (12.56 g) is used to replace compound Al, and the final product B12 is obtained: 0.56 g, MS (m / z) (M+): 1185.

[0212] 1 H NMR (400 MHz, CDC13) δ 7.54 (t, 1H), 7.51 (d, 1H), 7.45 (ddd, 7H), 7.41 - 7.33 (m, 12H), 7.27 (d, 2H), 7.25 - 7.17 (m, 4H), 7.14 (d, 1H), 7.12 - 7.06 (m, 2H), 7.04 (d, 1H), 6.97 (dd, 1H), 1.54-1.50 (s, 4H), 1.27-1.22 (m, 18H), 1.18 (s, 9H), 1.15-1.10 (m, 18H), 0.98-0.92 (m, 12H).

[0213] Synthesis Example 13

[0214]

[0215] The preparation method is the same as that of Synthesis Example 1, except that compound A13 (15.19 g) is used to replace compound Al, and the final product B13 is obtained: 0.85 g, MS (m / z) (M+): 1448.

[0216] 1H NMR (400 MHz, CDC13) δ 7.71 (d, 1H), 7.54 (dd, 4H), 7.51 (d, 1H), 7.49 - 7.42 (m, 6H), 7.41 - 7.29 (m, 15H), 7.29 - 7.18 (m, 7H), 7.08 (s, 1H), 7.00 (s, 2H), 6.67 (dd, 1H), 1.44-1.40 (m, 8H), 1.27 (s, 9H), 1.02-0.88 (m, 60H).

[0217] Synthesis Example 14

[0218]

[0219] The preparation method is the same as that of Synthesis Example 1, except that compound A14 (14.08 g) is used to replace compound Al, and finally product B14 is obtained: 0.74 g, MS (m / z) (M+): 1337.

[0220] 1 H NMR (400 MHz, CDC13) δ 7.71 (d, 1H), 7.54 (dd, 4H), 7.51 (d, 1H), 7.49 - 7.42 (m, 6H), 7.41 - 7.29 (m, 15H), 7.29 - 7.18 (m, 7H), 7.08 (s, 1H), 7.00 (s, 2H), 6.67 (dd, 1H), 1.44-1.40 (m, 8H), 1.27 (s, 9H), 1.02-0.88 (m, 60H).

[0221] Synthesis Example 15

[0222]

[0223] The preparation method is the same as that of Synthesis Example 1, except that compound A15 (15.39 g) is used to replace compound Al, and finally product B15 is obtained: 0.75 g, MS (m / z) (M+): 1467.

[0224] 1H NMR (400 MHz, CDC13) δ 8.16 (d, 1H), 7.62 - 7.51 (m, 8H), 7.50 - 7.41 (m, 7H), 7.41 - 7.33 (m, 14H), 7.31 (d, 5H), 7.27 (d, 2H), 7.25 - 7.17 (m, 2H), 7.00 (d, 2H), 6.67 (dd, 2H), 1.45-1.40 (t, 8H), 1.30 (s, 9H), 1.22 (s, 9H), 1.15-1.10 (m, 18H), 0.92-0.84 (m, 24H).

[0225] Synthesis Example 16

[0226]

[0227] The preparation method is the same as that of Synthesis Example 1, except that compound A16 (13.71 g) is used to replace compound Al, and finally product B16 is obtained: 0.64 g, MS (m / z) (M+): 1301.

[0228] 1 H NMR (400 MHz, CDC13) δ 8.16 (d, 1H), 7.62 - 7.51 (m, 8H), 7.50 - 7.41 (m, 7H), 7.41 - 7.33 (m, 14H), 7.31 (d, 5H), 7.27 (d, 2H), 7.25 - 7.17 (m, 2H), 7.00 (d, 2H), 6.67 (dd, 2H), 1.45-1.40 (t, 8H), 1.30 (s, 9H), 1.22 (s, 9H), 1.15-1.10 (m, 18H), 0.92-0.84 (m, 24H).

[0229] Synthesis Example 17

[0230]

[0231] The preparation method is the same as that of Synthesis Example 1, except that compound A17 (16.51 g) is used to replace compound Al, and finally product B17 is obtained: 0.66 g, MS (m / z) (M+): 1579.

[0232] 1H NMR (400 MHz, CDC13) δ 8.16 (d, 1H), 7.61 - 7.52 (m, 9H), 7.49 - 7.43 (m, 6H), 7.41 - 7.33 (m, 12H), 7.33 - 7.24 (m, 11H), 6.96 (s, 2H), 1.42-1.39 (m, 8H), 1.23-1.19 (m, 18H), 1.15-1.02 (m, 36H), 0.98-0.90 (m, 24H).

[0233] Synthesis Example 18

[0234]

[0235] The preparation method is the same as that of Synthesis Example 1, except that compound A18 (14.67 g) is used to replace compound Al, and finally product B18 is obtained: 0.92 g, MS (m / z) (M+): 1395.

[0236] 1 H NMR (400 MHz, CDC13) δ 8.16 (d, 1H), 7.61 - 7.52 (m, 9H), 7.49 - 7.43 (m, 6H), 7.41 - 7.33 (m, 12H), 7.33 - 7.24 (m, 11H), 6.96 (s, 2H), 1.42-1.39 (m, 8H), 1.23-1.19 (m, 18H), 1.15-1.02 (m, 36H), 0.98-0.90 (m, 24H).

[0237] Synthesis Example 19

[0238]

[0239] The preparation method is the same as that of Synthesis Example 1, except that compound A19 (13.11 g) is used to replace compound Al, and finally product B19 is obtained: 0.63 g, MS (m / z) (M+): 1239.

[0240] 1H NMR (400 MHz, CDC13) δ 8.50 (br, 1H), 7.54 (d, 2H), 7.34 (d, 9H), 7.28 (d, 4H), 7.18 (t, 9H), 6.95 (d, 1H), 6.76 (d, 2H), 6.56 (br, 2H), 6.04 (s, 1H), 1.70 (dd, 9H), 1.56 (s, 4H), 1.44 (d, 12H), 1.11 (s, 18H), 0.86-0.80 (m, 27H).

[0241] Synthesis Example 20

[0242]

[0243] The preparation method is the same as that of Synthesis Example 1, except that compound A20 (12.79 g) is used to replace compound Al, to finally obtain product B20: 0.74 g, MS (m / z) (M+): 1207.

[0244] 1 H NMR (400 MHz, CDC13) δ 8.50 (br, 1H), 7.54 (d, 2H), 7.34 (d, 9H), 7.28 (d, 4H), 7.18 (t, 9H), 6.95 (d, 1H), 6.76 (d, 2H), 6.56 (br, 2H), 6.04 (s, 1H), 1.70 (dd, 9H), 1.56 (s, 4H), 1.44 (d, 12H), 1.11 (s, 18H), 0.86-0.80 (m, 27H).

[0245] Synthesis Example 21

[0246]

[0247] The preparation method is the same as that of Synthesis Example 1, except that compound A21 (12.78 g) is used to replace compound Al, to finally obtain product B21: 0.71 g, MS (m / z) (M+): 1207.

[0248] 1H NMR (400 MHz, CDC13) δ 8.71 (s, 1H), 7.73 (t, 2H), 7.59 (d, 4H), 7.56 (d, 2H), 7.46 (t, 2H), 7.40 (dd, 9H), 7.33 (br, 2H), 7.31 (s, 1H), 7.30 - 7.27 (m, 2H), 7.23 (s, 2H), 7.21 (s, 3H), 7.19 (s, 1H), 6.92 (s, 1H), 6.75 (d, 2H), 6.62 (br, 2H), 6.12 (s, 1H), 1.45 (s, 9H), 1.43 (d, 18H), 1.10 (s, 9H), 0.86 (s, 18H).

[0249] Synthesis Example 22

[0250]

[0251] The preparation method is the same as that of Synthesis Example 1, except that compound A22 (12.78 g) is used to replace compound Al, to finally obtain product B22: 0.69 g, MS (m / z) (M+): 1207.

[0252] 1 H NMR (400 MHz, CDC13) δ 8.74 (s, 1H), 7.69 (s, 1H), 7.63 (d, 1H), 7.59 (d, 3H), 7.50 (d, 1H), 7.44 - 7.40 (m, 8H), 7.34 - 7.29 (m, 6H), 7.24 - 7.18 (m, 9H), 6.94 (s, 1H), 6.76 (d, 2H), 6.68 (br, 2H), 6.60 (br, 1H), 6.15 (s, 1H), 1.48 (s, 9H), 1.46 (d, 18H), 1.36 (s, 9H), 0.89 (s, 18H).

[0253] Synthesis Example 23

[0254]

[0255] The preparation method is the same as that of Synthesis Example 1, except that compound A23 (12.78 g) is used to replace compound Al, to finally obtain product B23: 0.62 g, MS (m / z) (M+): 1207.

[0256] 1 H NMR (400 MHz, CDC13) δ 8.78 (d, 1H), 7.63 (d, 1H), 7.57 (d, 2H), 7.54 - 7.47 (m, 3H), 7.43 (d, 1H), 7.42 - 7.36 (m, 10H), 7.32 (dt, 5H), 7.21 (t, 7H), 6.96 (s, 1H), 6.89 (s, 1H), 6.63 (d, 2H), 6.58 (d, 1H), 6.32 (s, 1H), 6.23 (s, 1H), 1.50 (s, 9H), 1.45 (s, 9H), 1.35 (d, 18H), 0.75 (s, 18H).

[0257] Synthesis Example 24

[0258]

[0259] The preparation method is the same as that of Synthesis Example 1, except that compound A24 (13.33 g) is used to replace compound Al, to finally obtain product B24: 0.58 g, MS (m / z) (M+): 1261.

[0260] 1 H NMR (400 MHz, CDC13) δ 8.78 (d, 1H), 7.63 (d, 1H), 7.57 (d, 2H), 7.54 - 7.47 (m, 3H), 7.43 (d, 1H), 7.42 - 7.36 (m, 10H), 7.32 (dt, 5H), 7.21 (t, 7H), 6.96 (s, 1H), 6.89 (s, 1H), 6.63 (d, 2H), 6.58 (d, 1H), 6.32 (s, 1H), 6.23 (s, 1H), 1.50 (s, 9H), 1.45 (s, 9H), 1.35 (d, 18H), 0.75 (s, 18H).

[0261] Synthesis Example 25

[0262]

[0263] The preparation method is the same as that of Synthesis Example 1, except that compound A25 (13.85 g) is used to replace compound Al, to finally obtain product B25: 0.60 g, MS (m / z) (M+): 1315.

[0264] 1 H NMR (400 MHz, CDCl3) δ 8.70 (s, 1H), 7.74 (d, 2H), 7.64 (s, 1H),7.61 (d, 1H), 7.56 (d, 1H), 7.48 (t, 3H), 7.44 (s, 1H), 7.42 (d, 3H), 7.39(d, 4H), 7.37 (d, 1H), 7.32 (s, 1H), 7.30 (s, 2H), 7.28 (s, 1H), 7.21 (t,7H), 6.91 (d, 2H), 6.64 (d, 2H), 6.55 (s, 1H), 6.37 (s, 1H), 6.15 (d, 1H),1.79 (s, 4H), 1.71 (d, 4H), 1.50 (d, 12H), 1.46 (d, 9H), 1.38 (s, 6H), 1.21(s, 9H), 1.08 (d, 6H), 0.79 (s, 18H)。

[0265] Synthesis Example 26

[0266]

[0267] The preparation method is the same as that of Synthesis Example 1, except that compound A26 (13.55 g) is used to replace compound Al, to obtain product B26: 0.58 g, MS (m / z) (M+): 1283.

[0268] 1 H NMR (400 MHz, CDCl3) δ 8.78 (d, 1H), 7.79 (d, 1H), 7.71 (d, 3H),7.65 (s, 3H), 7.59 (d, 5H), 7.53 (d, 4H), 7.45 (d, 3H), 7.41 (s, 3H), 7.39(d, 3H), 7.24 (s, 2H), 7.20 (s, 2H), 7.18 (s, 3H), 7.16 (s, 1H), 6.96 (s,1H), 6.91 (s, 1H), 6.65 (d, 2H), 6.38 (s, 1H), 6.25 (d, 1H), 1.45 (s, 9H),1.44 (s, 9H), 1.41 (s, 9H), 1.17 (s, 9H), 0.77 (s, 18H)。

[0269] Comparative Example

[0270] Some compounds tested in the research process are provided below, and the specific structural formula is:

[0271]

[0272] Compound performance evaluation

[0273] The vibration relaxation energy generated by the molecule in the excitation and emission process (excited state reorganization energy λ, unit: kJ / mol) is calculated, so that the influence of the compound provided by the application on the vibration relaxation of the compound after introducing the triphenylsilicon and benzofuran groups can be known. When the excited state reorganization energy is smaller, it means that the vibration relaxation occurring in the excitation process is smaller, and the luminescence spectrum will be narrower. The acquisition method is as follows: through ORCA6.0.1 software, based on the density functional theory (DFT) calculation method (the basis group level is set to: b3lyp-d3 / 6-31G(d), and the charge number is 0), the ground state structure of the molecule is geometrically optimized and vibration analysis (Opt+freq) is performed, based on the time-dependent density functional theory (TD-DFT) calculation method (the basis group level is set to: b3lyp-d3 / 6-31G(d), and the charge number is 0), the first single excitation state (S1) structure of the molecule is geometrically optimized and vibration analysis (Opt+freq) is performed, and all the structures obtained by calculation do not have virtual frequency; then through the dushin software based on the vibration mode of the molecule in the ground state and the first single excitation state of the molecule, the energy is decomposed, based on the Huang Kun factor and the wave number obtained by energy decomposition, the contribution of each vibration state to the reorganization energy is added, and the excited state reorganization energy λ (kJ / mol) of the fluorescent emission process of the compound provided by the application is calculated.

[0274] On the other hand, due to the Dexter energy transfer, the device efficiency will be low, by increasing the number of alkyl substituents to increase the intermolecular distance, and then reduce the probability of Dexter energy transfer. The acquisition method is as follows: the intermolecular distance is measured by XRD single crystal diffraction.

[0275] Table 1 lists the data of the excited state reorganization energy and the intermolecular distance of different compounds.

[0276] Table 1

[0277]

[0278] From the above table data, it can be seen that after introducing benzofuran and triphenylsilicon group substituents into the molecule at the same time, the energy loss due to vibration relaxation in the excitation process of the molecule can be significantly reduced. At the same time, while the multiple tert-butyl improves the intermolecular distance, the three phenyl groups on the triphenylsilicon also increase the intermolecular distance, which is conducive to improving the dispersion of the material in the device preparation process and reducing the probability of Dexter energy transfer.

[0279] Compared with the comparative compound D1, the energy loss caused by vibration relaxation in the excitation process can be significantly reduced by introducing benzofuran and triphenylsilyl group. As can be seen from the comparative compound D2 and the comparative compound D3, the separate use of benzofuran and triphenylsilyl group cannot cause significant influence on the reorganization energy of the excited state and the intermolecular distance. As can be seen from the comparative compound D4, when the number of tert-butyl groups is reduced, the intermolecular distance will be obviously reduced, thereby increasing the probability of occurrence of Dexter energy transfer.

[0280] Device embodiment

[0281] The anode of the following embodiments adopts the anode materials commonly used in the art, such as ITO, Ag or a multilayer structure thereof. The hole injection unit adopts the hole injection materials commonly used in the art, while being doped with F4TCNQ, HATCN, NDP-9 and the like. The hole transport unit adopts the hole transport materials commonly used in the art. The light-emitting unit adopts the light-emitting materials commonly used in the art, which can be composed of a host material and an emissive guest material doped with, for example, organic materials such as pyrene compounds or metal complexes (such as metal Ir, Pt and the like). The electron transport unit adopts the electron transport materials commonly used in the art. The electron injection layer adopts the electron injection materials commonly used in the art, such as LiQ, LiF, Yb and the like. The cathode adopts the materials commonly used in the art, such as metal Al, Ag or a metal mixture (Ag-doped Mg, Ag-doped Ca and the like).

[0282] The electrode preparation method and the deposition method of each functional layer in the following embodiments are all the conventional methods in the art, such as vacuum thermal evaporation or inkjet printing, which will not be described here again. Only some process details in the preparation process and test methods are supplemented as follows:

[0283] Device embodiment 1

[0284] This embodiment provides a blue organic electroluminescent device, and the preparation method thereof is as follows: after patterning the ITO substrate to have a light-emitting area with a size of 3 mm x 3 mm, ultrasonicating with water / isopropanol, UV / ozone irradiation and then drying at 100℃, the ITO substrate is installed on the substrate support of a vacuum deposition device and the pressure is adjusted to make the vacuum rate become 1 x 10 - 7torr. Then, a hole injection layer was formed by vacuum depositing compound HT01 and compound PD01 (mass ratio of compound HT01 to compound PD01 was 97:3) on the ITO layer (anode) of the substrate at a thickness of 10 nm, a hole transport layer was formed by vacuum depositing compound HT01 on the hole injection layer at a thickness of 100 nm, a light-emitting auxiliary layer was formed by vacuum depositing compound BP01 on the hole transport layer at a thickness of 5 nm, a light-emitting layer was formed by vacuum depositing a mixture of compound B1 provided by the application and compound BH01 on the light-emitting auxiliary layer at a thickness of 20 nm, wherein BH01 was used as a host material, compound B1 was used as a guest material, and the mass ratio of compound BH01 to compound B1 was 98:2, a hole blocking layer was formed by vacuum depositing compound HB01 on the light-emitting layer at a thickness of 5 nm, an electron transport layer was formed by vacuum depositing compound ET01 and compound LiQ (mass ratio of compound ET01 to compound LiQ was 1:1) on the hole blocking layer at a thickness of 30 nm, an electron injection layer was formed by vacuum depositing Yb on the electron transport layer at a thickness of 1 nm, a cathode was formed by depositing Mg and Ag (mass ratio of Mg to Ag was 1:9) on the electron injection layer at a thickness of 15 nm, and a cover layer was formed by depositing compound CP01 on the cathode at a thickness of 50 nm. Finally, the substrate after evaporation was encapsulated, a coating device was used to perform a coating process on the cleaned cover plate with UV glue, the cover plate coated by the coating device was moved to a pressing section, the substrate after evaporation was placed on the upper end of the cover plate, and the substrate and the cover plate were bonded under the action of a bonding device, and the UV glue was cured by light at the same time, thereby preparing a top-emitting organic electroluminescent device. The device structure is shown in Figure 1 .

[0285] The molecular structural formula of each layer material except the blue light doping material is as follows:

[0286]

[0287]

[0288] .

[0289] Device Examples 2-26

[0290] In this example, a blue light organic electroluminescent device was prepared by replacing compound B1 in the device example 1 with compounds B2 to B26 provided in compound examples 2 to 26 to form a light-emitting layer, and other preparation steps were the same as those in the device example 1.

[0291] Device Comparative Examples 1-4

[0292] The method is the same as in device example 1, except that compound B1 in device example 1 is replaced by compounds D1 to D5 respectively to form the light-emitting layer, and other preparation steps are the same as in device example 1, and blue light organic electroluminescent devices are respectively prepared.

[0293] Performance evaluation of organic electroluminescent devices

[0294] The OLED devices described above were tested by standard methods. To this end, the driving voltage, luminance, electroluminescent current efficiency (measured in cd / A) and external quantum efficiency (EQE, measured in percent) of the organic electroluminescent device were determined at a current density of J = 10 mA / cm 2 2 and L1 = 97% means that the luminous intensity decreases to 97% of its initial value L0 after a time LT when operating at 20 mA / cm 2 2 The lifetime (LT97) of the organic electroluminescent device was determined at a current density of J = 20 mA / cm

[0295] The data of various OLED devices are summarized in Table 2. The various parameters of the device examples and device comparative examples are compared, showing the performance data of various OLED devices.

[0296] The test instruments and methods for performance testing of the above-mentioned example, comparative example OLED devices are as follows:

[0297] Quantum efficiency C.E (cd / A), color coordinates (CIEy) and emission half-peak width were tested using a spectral scanner PhotoResearch PR-655;

[0298] Current density and turn-on voltage: tested using a digital source meter Keithley 2400;

[0299] Blue index is obtained by dividing the quantum efficiency C.E (cd / A) by the color coordinates (CIEy);

[0300] Lifetime test: LT-96ch lifetime test device was used.

[0301] Table 2 Blue light device performance test results

[0302] ​​

[0303] From the verification results of the device embodiments, it can be seen that after introducing the benzofuran and triphenylsilicon substituents into the molecule at the same time, compared with the same poly-t-butyl structure, due to the reduction of energy loss of the molecule in the excitation process, the working efficiency of the device is significantly improved. In addition, due to the inhibition of vibration relaxation, it also brings the effect of reducing the emission half-width and improving the color purity, with the characteristics of narrow spectrum, meeting the requirements of the BT.2020 wide color gamut standard for spectrum.

[0304] The above merely describes the preferred embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A polycyclic compound containing triphenylsilane and polyalkyl substituents, characterized in that, The general structural formula of the polycyclic compound is shown below: I-1、 I-2、 I-3、 I-4; R1 and R2 are represented independently. , , One of them; When R1 represents tert-butyl, two adjacent R1 positions can be connected to each other to form a ring structure; When R2 represents tert-butyl, two adjacent R2 positions can be connected to form a ring structure; R3 represents one of the following structures: 、 、 ； R4 represents one of the following structures: 、 、 、 ； n represents 0, 1, 2, 3, or 4; m represents 1 or 2; The polycyclic compound contains at least one 5 tert-butyl groups; or A ring structure consisting of three tert-butyl groups and one ring formed by connecting any two adjacent tert-butyl groups. Any hydrogen atom in the R3 and R4 groups can be replaced by deuterium or tert-butyl, and at least one hydrogen atom in the above groups is replaced by tert-butyl. When more than one hydrogen atom is replaced, two adjacent tert-butyl groups can be linked together to form a ring structure.

2. The polycyclic compound according to claim 1, characterized in that, R3 represents one of the following structures: 、 、 、 、 ； and / or R4 represents one of the following structures: 、 、 、 、 、 。 3. The polycyclic compound according to claim 1, characterized in that, The polycyclic compounds are selected from the structures shown below: 。 4. An organic electroluminescent device, characterized in that, It includes an anode, a hole transport region, a light-emitting layer, an electron transport region, and a cathode sequentially disposed on a substrate; wherein the light-emitting layer includes a host material and a dopant material, and the dopant material includes one or more polycyclic compounds as described in any one of claims 1-3.

5. The organic electroluminescent device according to claim 4, characterized in that, The main material is selected from the following general structure: II; in, L is selected from single bonds or phenylene; Ar1 is selected from phenyl or naphthyl; Ar2 represents one of the following groups: 、 、 、 ； In Formula II, any one of the hydrogen atoms can be replaced by deuterium.

6. The organic electroluminescent device according to claim 4, characterized in that, The main material is selected from the structure shown below: 。

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