Preparation and properties of propeller type tetraphenyl ethylene-triphenylene quadruplex discotic liquid crystal

Abstract

The invention belongs to the field of organic material chemistry, and discloses a preparation method and properties of propeller type tetraphenyl ethylene-triphenylene quadruplex discotic liquid crystal, and the propeller type tetraphenyl ethylene-triphenylene quadruplex discotic liquid crystal has a structure as shown in a general formula I. The compound shown in the general formula I is mainly synthesized from tetrabromo-tetraphenylethylene and a benzophenanthrene boric acid ester derivative through Suzuki coupling reaction, the atom utilization rate is high, and the steps are simple and efficient. The compound has thermotropic liquid crystal property, the TPE-TP4 is a smectic phase or a plastic crystal phase, the introduction of thiophene bridging stabilizes a columnar liquid crystal phase, and the temperature of a columnar intermediate phase of the TPE-ThTP4 reaches 213 DEG C or above. The TPE-TP4 and the TPE-ThTP4 both have an aggregation-induced emission enhancement effect, and the fluorescence quantum yield of the solution reaches 84% and 30%. The maximum responsivity of the photoconductive detector prepared by taking the TPE-TP4 as the absorption layer is 4.43 A / W and 8.35 A / W respectively at the wavelength of 650 nm and the wavelength of 405 nm.

Description

Technical Field

[0001] The present invention belongs to the field of organic material chemistry, and particularly relates to the preparation and properties of a propeller-shaped tetraphenylethylene-tetracene tetramer discotic liquid crystal. Background Art

[0002] In the past few decades, organic small molecule discotic liquid crystals (DLCs) have been widely studied as a typical soft matter. The volume, orientation of the aromatic nucleus in the molecular structure, and molecular symmetry are the main influencing factors for the formation of thermotropic columnar liquid crystal mesophases. Commonly reported planar central aromatic nuclei include tetracene, perylene diimide, hexabenzocoronene, pyrene, carbazole, fused thiophene, etc. Generally, such luminescent discotic liquid crystal materials are widely used in the fields of organic thin film optoelectronic devices such as organic field effect transistors (OFETs), organic light emitting diodes (OLEDs), and organic solar cells (OSCs). In recent years, organic discotic liquid crystal molecules with aggregation-induced emission (AIE) effects, such as 1,3,5-triazine, cyanostilbene, tetraphenylthiophene, tetraphenylethylene, etc., have been reported, but the number of peripheral mesogenic groups is small or the degree of condensation is low, and most are connected by flexible chains or electron-withdrawing groups. In the mesophase, the internal packing and emission characteristics of their twisted multimer molecules are not yet accurately understood. Therefore, inventing a class of aggregation-induced emission discotic liquid crystal molecules (AIE-DLCs) with a rigid bridge and large conjugated polycyclic aromatic hydrocarbons on the periphery is expected to enrich the multifunctional applications of discotic liquid crystals as optoelectronic functional materials.

[0003] Based on this, we designed and synthesized a class of tetraphenylethylene-tetracene tetramer compounds, and focused on comparing and studying the properties of tetramer discotic compounds with direct σ-bond connection (TPE-TP4) and electron-rich thiophene rings as rigid bridges (TPE-ThTP4) in terms of liquid crystallinity, self-assembly order, photophysical properties, and gelation, and explored the application of TPE-TP4 as an organic thin film in photodetectors, laying a foundation for the further design and construction of organic luminescent discotic liquid crystal materials. Summary of the Invention

[0004] The object of the present invention is to provide a preparation method and properties of a propeller-shaped tetraphenylethylene-tetracene tetramer discotic liquid crystal.

[0005] In the synthesis of such compounds, mainly using inexpensive 3,4-dimethoxybromobenzene and o-bromoanisole as raw materials, first through FeCl3-catalyzed coupling, n-BuLi substitution and debromination gave tetramethoxybiphenyl M2, which further underwent an intermolecular Scholl oxidative cyclization reaction with o-bromoanisole in a dichloromethane solution of FeCl3 / CH3NO2 to obtain pentamethoxy-substituted monobromobenzophenanthrene M3. At this time, a two-step reaction of BBr3 demethylation and etherification of bromohexane under the action of a base was carried out in series to generate pentahexyloxy-substituted monobromobenzophenanthrene M4. The yields of each of the above steps were all above 70%. On this basis, on the one hand, monobromobenzophenanthrene M4 reacted with bis(pinacolato)diboron to generate intermediate pentahexyloxybenzophenanthrene borate M5, and on the other hand, it first underwent a Suzuki-Miyaura coupling reaction with 2-thiopheneboronic acid to form M6, and then reacted with n -BuLi and isopropyl alcohol pinacol borate were synthesized in series to obtain intermediate benzophenanthrene thiophene borate derivative M7. Finally, the obtained intermediates M5 and M7 were respectively subjected to Suzuki-Miyaura cross-coupling reactions with commercially available tetrakis(4-bromophenyl)ethylene under Pd catalysis to efficiently obtain tetraphenylethylene-benzophenanthrene tetrameric discotic liquid crystal compounds TPE-TP4 and TPE-ThTP4, with yields of 85% and 54% respectively. For the target compounds obtained in this invention, their mesomorphic properties, self-assembly, photophysical properties, and gel properties were preliminarily studied. Studies have shown that they have a relatively wide mesomorphic temperature range, can form stable smectic phases (plastic crystal phases) or columnar phases, and at the same time, these compounds also have good optoelectronic properties in solution or the aggregated state, and have potential applications in organic optoelectronic functional devices.

[0006] To achieve the above invention purpose, the technical solution adopted is: a propeller-shaped tetraphenylethylene-benzophenanthrene tetrameric discotic liquid crystal compound, characterized in that the compound has the following structure I; wherein R=-C n H 2n+1 , {n|6 < n < 14, n ∈ Z *}; Ar is a rigid (or semi-rigid, flexible) spacer group, and common ones can be aromatic rings, single heterocycles, fused heterocycles, and their derivatives, etc. The content of this invention involves direct connection by σ single bonds and connection by a rigid thiophene ring.

[0007]

[0008] Compared with the prior art, the beneficial effects of the propeller-shaped tetraphenylethylene-tetracene tetrameric discotic liquid crystal compound of general formula I of the present invention are as follows: First, the chemical structure is diverse, and the liquid crystal properties can be adjusted by adjusting different R groups and their chain lengths as well as the types of Ar, enabling the target compound to have rich phase states, a wide mesomorphic temperature range, excellent optoelectronic functional properties, etc., and thus having a wide range of uses in the fields of organic light-emitting diodes, organic field-effect transistors, organic photovoltaics, etc. Second, in the method of the present invention, the used drugs and reagents are inexpensive and easily available, the reaction conditions are mild, the atom utilization rate is high, the steps are simple and efficient, and the post-treatment operation is simple and the yield is relatively high, meeting the basic requirements of laboratory or industrial production.

[0009] The preparation method of the above-mentioned propeller-shaped tetraphenylethylene-tetracene tetrameric discotic liquid crystal compound of general formula I is simple and efficient, and the liquid crystal performance is excellent. The following further elaborates on the present invention in combination with specific implementation cases. Description of the Drawings

[0010] Figure 1 1H NMR spectrum of the precursor compound M1 obtained in Example 1.

[0011] Figure 2 13C NMR spectrum of the precursor compound M1 obtained in Example 1.

[0012] Figure 3 1H NMR spectrum of the precursor compound M2 obtained in Example 2.

[0013] Figure 4 13C NMR spectrum of the precursor compound M2 obtained in Example 2.

[0014] Figure 5 1H NMR spectrum of the precursor compound M3 obtained in Example 3.

[0015] Figure 6 13C NMR spectrum of the precursor compound M3 obtained in Example 3.

[0016] Figure 7 1H NMR spectrum of the precursor compound M4 obtained in Example 4.

[0017] Figure 8 13C NMR spectrum of the precursor compound M4 obtained in Example 4.

[0018] Figure 9 High-resolution mass spectrum of the precursor compound M4 obtained in Example 4.

[0019] Figure 10 1H NMR spectrum of the intermediate compound M5 obtained in Example 5.

[0020] Figure 11 13C NMR spectrum of intermediate compound M5 obtained in Example 5.

[0021] Figure 12 High resolution mass spectrum of intermediate compound M5 obtained in Example 5.

[0022] Figure 13 1H NMR spectrum of intermediate compound M6 obtained in Example 6.

[0023] Figure 14 13C NMR spectrum of intermediate compound M6 obtained in Example 6.

[0024] Figure 15 High resolution mass spectrum of intermediate compound M6 obtained in Example 6.

[0025] Figure 16 1H NMR spectrum of intermediate compound M7 obtained in Example 7.

[0026] Figure 17 13C NMR spectrum of intermediate compound M7 obtained in Example 7.

[0027] Figure 18 High resolution mass spectrum of intermediate compound M7 obtained in Example 7.

[0028] Figure 19 1H NMR spectrum of target compound TPE-TP4 obtained in Example 8.

[0029] Figure 20 13C NMR spectrum of target compound TPE-TP4 obtained in Example 8.

[0030] Figure 21 High resolution mass spectrum of target compound TPE-TP4 obtained in Example 8.

[0031] Figure 22 Polarized optical texture image of target compound TPE-TP4 obtained in Example 8.

[0032] Figure 23 DSC chart of target compound TPE-TP4 obtained in Example 8.

[0033] Figure 24 XRD chart of target compound TPE-TP4 obtained in Example 8.

[0034] Figure 25 1H NMR spectrum of target compound TPE-ThTP4 obtained in Example 9.

[0035] Figure 2613C NMR spectrum of the target compound TPE-ThTP4 obtained in Example 9.

[0036] Figure 27 High-resolution mass spectrum of the target compound TPE-ThTP4 obtained in Example 9.

[0037] Figure 28 Polarized optical texture image of the target compound TPE-ThTP4 obtained in Example 9.

[0038] Figure 29 DSC chart of the target compound TPE-ThTP4 obtained in Example 9.

[0039] Figure 30 XRD chart of the target compound TPE-ThTP4 obtained in Example 9.

[0040] Figure 31 TGA charts of the target compounds TPE-TP4 and TPE-ThTP4 obtained in Examples 8-9.

[0041] Figure 32 UV-Vis absorption spectra of the target compounds TPE-TP4 and TPE-ThTP4 obtained in Examples 8-9 in organic solvents.

[0042] Figure 33 Fluorescence emission spectra of the target compounds TPE-TP4 and TPE-ThTP4 obtained in Examples 8-9 in organic solvents.

[0043] Figure 34 UV-Vis absorption spectra of the target compounds TPE-TP4 and TPE-ThTP4 obtained in Examples 8-9 in tetrahydrofuran solvents with gradient water contents.

[0044] Figure 35 Fluorescence emission spectra of the target compounds TPE-TP4 and TPE-ThTP4 obtained in Examples 8-9 in tetrahydrofuran solvents with gradient water contents.

[0045] Figure 36 Aggregation-induced fluorescence photographs of the target compounds TPE-TP4 and TPE-ThTP4 obtained in Examples 8-9 in tetrahydrofuran solvents with gradient water contents.

[0046] Figure 37 Inverted image of the organic gel and SEM image of the xerogel of the target compound TPE-ThTP4 obtained in Example 9.

[0047] Figure 38For the application of the target compound TPE-TP4 obtained in Example 8 as an organic thin film material in an ultraviolet-visible organic photoconductive detector, where (a) is the I-V characteristic curve and the corresponding structural diagram under dark and 650 nm light illumination, (b) is the I-T diagram at a wavelength of 650 nm, (c) is the photocurrent curve at different incident light powers, and (d) is the correlation curve of the change trends of photocurrent and responsivity with light power density.

[0048] Figure 39 For the application of the target compound TPE-ThTP4 obtained in Example 9 as an organic thin film material in an ultraviolet-visible organic photoconductive detector, where (a) is the I-V characteristic curve and the corresponding structural diagram under dark and 650 nm light illumination, (b) is the I-T diagram at a wavelength of 650 nm, (c) is the photocurrent curve at different incident light powers, and (d) is the correlation curve of the change trends of photocurrent and responsivity with light power density.

[0049] Figure 40 For the specified abstract drawing of the specification, where Ⅰ is the general formula of a propeller-shaped tetraphenylethylene-tetracene tetramer discotic liquid crystal compound. Detailed implementation mode

[0050] The present invention will be further elaborated through specific examples below, but it is not used to limit the protection scope of the present invention. Without departing from the concept of the present invention, those skilled in the art can make improvements to the preparation method and the instruments used within the scope of the claims, and these improvements should also be regarded as the protection scope of the present invention.

[0051] Example 1: Synthesis of precursor M1 (2,2'-dibromo-4,4',5,5'-tetramethoxybiphenyl) A preparation method of 2,2'-dibromo-4,4',5,5'-tetramethoxybiphenyl M1, and its synthesis and steps are as follows: At room temperature, a solution of FeCl3 (26.15 g, 161.24 mmol) dissolved in CH3NO2 (30.0 mL) was added to a solution of 4-bromo-1,2-dimethoxybenzene (10.00 g, 46.07 mmol) stirred in dry CH2Cl2 (100.0 mL). After 1 hour, cold methanol (20.0 mL) and water (20.0 mL) were added to quench the reaction suddenly. It was extracted with CH2Cl2 and purified by silica gel column chromatography (petroleum ether / CH2Cl2, 1:3, v / v), and recrystallized from petroleum ether to obtain white solid M1 (6.97 g, 70%). In this example, the structure of precursor M1 was identified by 1H NMR and 13C NMR spectra: 11H NMR (CDCl3, TMS, 600 MHz) δ (ppm): 7.11 (d, J J = 2.4 Hz, 2H), 6.76 (d, J J = 2.4 Hz, 2H), 3.92 - 3.91 (m, 6H), 3.87 - 3.86 (m, 6H). 13 13C NMR (CDCl3, 151 MHz) δ (ppm): 149.10, 147.98, 133.96, 115.05, 113.90, 56.18, 56.13。

[0052] Example 2: Synthesis of Precursor M2 (Tetramethoxybiphenyl) A preparation method of tetramethoxybiphenyl M2, the synthesis and steps are as follows: In a single-necked RBF tube equipped with a stopcock, at -78 °C, M1 (18.00 g, 41.66 mmol) was dissolved in THF (150.0 mL), and 2.5 M n n-BuLi (49.98 mL, 124.97 mmol) was added dropwise under an argon atmosphere. After stirring at -78 °C for 30 minutes, the solution was slowly warmed to room temperature and stirred for another 3 hours. Then methanol (20.0 mL) was added to quench the solution, and the solution was extracted with ethyl acetate. It was purified by silica gel column chromatography (pure CH2Cl2) and recrystallized from petroleum ether to obtain white solid M2 (9.38 g, 82%). In this example, the structure of precursor M1 was identified by 1H NMR and 13C NMR: 1 1H NMR (CDCl3, TMS, 600 MHz) δ (ppm): 7.10 (d, J J = 2.1 Hz, 1H), 7.09 (d, J J = 2.1 Hz, 1H), 7.06 (d, J J = 2.1 Hz, 2H), 6.94 (s, 1H), 6.92 (s, 1H), 3.95 (s, 6H), 3.92 (s, 6H). 13 13C NMR (CDCl3, 151 MHz) δ (ppm): 149.07, 148.29, 134.20, 119.08, 111.45, 110.36, 55.97, 55.95。

[0053] Example 3: Synthesis of Precursor M3 (Pentamethoxy-substituted Monobromobenzophenanthrene) A preparation method of pentamethoxy-substituted monobromobenzophenanthrene M3, and its synthesis and steps are as follows: At room temperature, M2 (9.00 g, 32.81 mmol) and 2-bromoanisole (9.20 g, 49.21 mmol) were stirred in dry CH2Cl2 (100.0 mL), and then a solution of FeCl3 (31.93 g, 196.85 mmol) dissolved in CH3NO2 (20.0 mL) was added to the above solution. After 2 hours, the solution was poured into ice water (30.0 mL)-methanol (30.0 mL), and stirred at room temperature for another 10 minutes to obtain a precipitate product. Subsequently, the mixture was filtered through a Buchner funnel, and the residue was purified by silica gel column chromatography (pure CH2Cl2) and recrystallized from ethanol to obtain off-white powder M3 (11.16 g, 74%). In this example, the structure of the precursor M3 was identified by 1H NMR and 13C NMR: 1 H NMR (CDCl3, TMS, 600 MHz) δ (ppm): 8.08 (s, 1H), 7.50 (s, 1H), 7.41 (s, 1H), 7.36 (s, 1H), 7.32 (s, 1H), 7.19 (s, 1H), 4.10 (s, 6H), 4.05 (s, 6H), 4.00 (s, 3H). 13 C NMR (CDCl3, 151 MHz) δ (ppm): 153.43, 149.23, 148.46, 148.31, 128.76, 127.28, 124.07, 123.60, 122.48, 122.13, 121.91, 111.10, 104.01, 103.74, 103.56, 103.42, 56.06, 55.95, 55.87, 55.84.

[0054] Example 4: Synthesis of precursor M4 (pentakis(hexyloxy)-substituted monobromobenzophenanthrene) A preparation method of pentakis(hexyloxy)-substituted monobromobenzophenanthrene M4, and its synthesis and steps are as follows: Under argon, M3 (4.40 g, 9.62 mmol) was added to a Schlenk reaction tube and stirred with dry CH2Cl2 (20.0 mL). The above mixture was placed at -78 °C, and then BBr3 (6.49 mL, 67.35 mmol) was injected into the reaction system and stirred overnight. Then, the solution was poured into ice water (200.0 mL) and stirred until the mixture returned to room temperature. Subsequently, the mixture was filtered through a Buchner funnel (filled with double-layer filter paper), and the residue was dried under argon to obtain a purple-black solid, 11-bromotriphenylene-2,3,6,7,10-pentol. Immediately, in a 250 mL round-bottom flask, 11-bromotriphenyl-2,3,6,7,10-pentol, n-hexyl bromide (9.53 g, 57.73 mmol), K2CO3 (15.96 g, 115.46 mmol), zinc powder (314.6 mg, 4.81 mmol), and KI (798.6 mg, 4.8 mmol) were added, and the solvent DMF (70.0 mL) was added. The system was heated to 90 °C and stirred for 24 hours. Then, the hot mixture was immediately poured into ice water in a 500 mL beaker, and dilute hydrochloric acid was added to the solution until the system was acidic. It was filtered through a Buchner funnel (filled with double-layer filter paper), and the solvent was evaporated. The product was purified by silica gel column chromatography (CH2Cl2 / petroleum ether, 1:2, v / v) and recrystallized from ethyl acetate and ethanol to obtain a white solid M4 (5.61 g, 72%). In this example, the precursor M4 was identified by 1H NMR, 13C NMR, and high-resolution mass spectrometry: 1 1H NMR (CDCl3, TMS, 600 MHz) δ (ppm): 8.56 (s, 1H), 7.83 (s, 1H), 7.78 - 7.77 (m, 3H), 7.75 (s, 1H), 4.25 - 4.21 (m, 10H), 1.99 - 1.92 (m, 10H), 1.63 - 1.56 (m, 10H), 1.44 - 1.37 (m, 20H), 0.96 - 0.93 (m, 15H). 1313C NMR (CDCl3, 151 MHz) δ(ppm): 153.57, 149.96, 149.34, 149.00, 148.79, 129.30, 127.71, 124.81, 124.07, 123.11, 122.79, 122.68, 112.23, 107.64, 107.21, 106.78, 106.13, 105.67, 69.83, 69.77, 69.46, 69.43, 69.25, 31.68, 31.66, 31.60, 29.41, 29.40, 29.34, 29.33, 29.18, 25.84, 25.82, 25.80, 22.65, 22.62, 14.05. HRMS (MALDI): [M] + calcd for C 48 H 71 BrO5, m / z: 806.4485 (100.0%), 808.4464 (97.3%), 807.4518 (51.9%), 809.4498 (50.5%), 810.4532 (12.8%); found, 806.4484, 808.4464, 807.4517, 809.4497, 810.4531。

[0055] Example 5: Synthesis of Intermediate M5 (Pentahexyloxybenzophenanthrene Borate) A method for preparing pentahexyloxybenzophenanthrene borate M5, the synthesis and steps are as follows: In a dry flask under argon atmosphere protection, add M4 (2.6 g, 3.22 mmol), bis(pinacolato)diboron (1.80 g, 7.08 mmol), Pd(dppf)Cl2·CH2Cl2 (131.4 mg, 0.16 mmol) and CH3COOK (947.4 mg, 9.65 mmol). After adding 1,4-dioxane (70.0 mL), the reactants are stirred at 90 °C for 24 hours. Then, the reaction mixture is cooled to room temperature and extracted with CH2Cl2. The combined organic layers are dried over anhydrous MgSO4, evaporated, and the residue is purified by column chromatography (eluent petroleum ether / CH2Cl2, 1:3, v / v). Recrystallization from ethyl acetate and ethanol gives white solid M5 (1.92 g, 70%). In this example, the structure of intermediate M5 was identified by 1H NMR, 13C NMR and high resolution mass spectrometry: 11H NMR (CDCl3, TMS, 600 MHz) δ (ppm): 8.04 (d, J J = 11.1 Hz, 1H), 7.91 (d, J J = 11.3 Hz, 1H), 7.82 - 7.81 (m, 2H), 7.82 - 7.81 (m, 1H), 6.09 (s, 1H), 4.32 - 4.20 (m, 10H), 1.98 - 1.93 (m, 10H), 1.64 - 1.58 (m, 10H), 1.44 (s, 6H), 1.40 - 1.35 (m, 20H), 1.26 (s, 6H), 0.94 (t, J J = 6.9 Hz, 15H). 8.04 (d, J J = 11.1 Hz, 1H), 7.91 (d, J J = 11.3 Hz, 1H), 7.82 - 7.81 (m, 2H), 7.82 - 7.81 (m, 1H), 6.09 (s, 1H), 4.32 - 4.20 (m, 10H), 1.98 - 1.93 (m, 10H), 1.64 - 1.58 (m, 10H), 1.44 (s, 6H), 1.40 - 1.35 (m, 20H), 1.26 (s, 6H), 0.94 (t, J J = 6.9 Hz, 15H). 13 13C NMR (CDCl3, 151 MHz) δ (ppm): 162.01, 150.34, 149.45, 148.86, 148.64, 132.67, 132.63, 125.71, 124.16, 122.88, 108.25, 107.38, 106.76, 106.68, 102.98, 69.98, 69.84, 69.37, 69.33, 68.51, 31.68, 31.66, 31.56, 29.44, 29.36, 29.33, 25.88, 25.84, 22.65, 22.55, 14.05, 14.00. HRMS (MALDI): [M] + calcd for C 54 H 83BO7, m / z: 854.6232 (100.0%), 855.6265 (48.7%), 853.6268 (24.8%), 856.6299 (14.3%), 855.6265 (9.7%); found, 854.6220, 855.6255, 853.6258, 856.6289, 857.6325。

[0056] Example 6: Synthesis of Intermediate M6 (Pentahexyloxybenzoporphyrin-thiophene) A preparation method of pentahexyloxybenzoporphyrin-thiophene M6, and its synthesis and steps are as follows: Under an argon atmosphere, M4 (1.00 g, 1.24 mmol), 2-thiopheneboronic acid (237.5 mg, 1.86 mmol), K2CO3 (855.2 mg, 6.19 mmol) and Pd(PPh3)4 (143.0 mg, 0.12 mmol) were added to a reaction tube. Degassed water (5.0 mL) and THF (15.0 mL) were injected into the reaction mixture. The mixture was stirred at 70 °C for 24 hours. Then, it was cooled, extracted with CH2Cl2 and dried over MgSO4. The organic solvents were removed by distillation, and the residue was purified by silica gel column chromatography (petroleum ether / CH2Cl2, 2:1, v / v). Recrystallization from ethyl acetate and ethanol gave white solid M6 (926.4 mg, 92%). In this example, the structure of intermediate M6 was identified by 1H NMR, 13C NMR and high-resolution mass spectrometry: 1 1H NMR (CDCl3, TMS, 600 MHz) δ (ppm): 8.67 (s, 1H), 7.95 (s, 1H), 7.89 (s, 1H), 7.83 (s, 1H), 7.82 (s, 2H), 7.70 (dd, J J = 3.6, 1.2 Hz, 1H), 7.41 (dd, J J = 5.1, 1.2 Hz, 1H), 7.18 (dd, J J = 5.1, 3.6 Hz, 1H), 4.30 (t, J J = 6.4 Hz, 2H), 4.26 - 4.22 (m, 8H), 2.02 - 1.93 (m, 10H), 1.64 - 1.57 (m, 10H), 1.45 - 1.38 (m, 20H), 0.96 - 0.93 (m, 15H). 1313C NMR (CDCl3, 151 MHz) δ (ppm): 153.99, 149.88, 149.26, 148.90, 148.80, 139.97, 129.30, 126.84, 125.68, 125.63, 124.90, 123.82, 123.25, 123.19, 123.04, 122.99, 122.81, 107.94, 107.51, 106.98, 106.73, 104.57, 69.90, 69.82, 69.50, 69.42, 68.98, 31.69, 31.65, 29.44, 29.37, 29.31, 26.03, 25.85, 22.66, 22.60, 14.05. HRMS (MALDI): [M] + calcd for C 52 H 74 O5S, m / z: 810.5257 (100.0%), 811.5291 (56.2%), 812.5324 (15.5%), 812.5215 (4.5%); found, 810.5253, 811.5281, 812.5294, 813.5338。

[0057] Example 7: Synthesis of Intermediate M7 (Benzo[b]thiophene Borate Derivative) A method for preparing a benzo[b]thiophene borate derivative M7, the synthesis and steps are as follows: In a reaction tube, dissolve M6 (811.0 mg, 1.00 mmol) in THF (20.0 mL) at -78 °C, and dropwise add 2.5 M n -BuLi (0.60 mL, 1.50 mmol) under an argon atmosphere. Stir the mixture at -78 °C for another 2 hours. Then quickly inject 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (372.0 mg, 2.00 mmol) into the solution. After stirring at -78 °C for 30 minutes, stir the solution at room temperature overnight. Extract the reactant with CH2Cl2, wash the combined organic layers with brine, and dry over anhydrous MgSO4, and evaporate under reduced pressure. The residue is purified by silica gel column chromatography using petroleum ether / CH2Cl2 as the eluent (1:3, v / v) and recrystallized from ethyl acetate and ethanol to obtain a gray-green solid M7 (534.1 mg, 57%). In this example, the structure of intermediate M7 was identified by 1H NMR, 13C NMR, and high-resolution mass spectrometry: 11H NMR (CDCl3, TMS, 600 MHz) δ (ppm): 8.68 (s, 1H), 7.94 (s, 1H), 7.88 (s, 1H), 7.83 (d, J J = 1.9 Hz, 1H), 7.82 (s, 2H), 7.80 - 7.78 (m, 1H), 7.72 - 7.70 (m, 1H), 4.30 (t, J J = 6.3 Hz, 2H), 4.28 - 4.22 (m, 8H), 2.01 - 1.94 (m, 10H), 1.64 - 1.58 (m, 10H), 1.51 (s, 3H), 1.41 - 1.40 (m, 29H), 0.95 (t, J J = 6.1 Hz, 15H). 13 13C NMR (CDCl3, 151 MHz) δ (ppm): 154.18, 149.90, 149.35, 148.90, 148.74, 147.27, 137.47, 129.65, 127.66, 126.81, 124.98, 123.85, 123.82, 123.13, 122.91, 122.79, 107.85, 107.45, 106.85, 106.65, 104.68, 84.01, 69.83, 69.80, 69.47, 69.43, 68.94, 31.69, 31.67, 29.43, 29.42, 29.36, 29.29, 26.07, 25.87, 25.84, 25.42, 24.77, 22.65, 22.58, 14.05. HRMS (MALDI): [M] + calcd for C 58 H 85 BO7S, m / z: 936.6109 (100.0%), 937.6143 (53.0%), 935.6145 (24.8%), 938.6176 (19.3%), 936.6179 (9.9%); found, 936.6110, 937.6144, 935.6147, 938.6177, 939.6212。

[0058] Example 8: Synthesis of the target compound TPE - TP4 (tetraphenylethylene - benzophenanthrene tetramer compound) A preparation method of a tetraphenylethylene-tetraphenylporphyrin tetramer compound TPE-TP4, and its synthesis and steps are as follows: In an argon atmosphere, 1,1,2,2-tetrakis(4-bromophenyl)ethylene (64.8 mg, 0.10 mmol), M5 (527.5 mg, 0.50 mmol), K2CO3 (276.4 mg, 2.00 mmol) and Pd(PPh3)4 (34.7 mg, 0.03 mmol) were mixed and stirred in a H2O / THF (3.0 mL / 9.0 mL) solvent. The mixture was heated to 70 °C with stirring for 48 hours. After cooling, the mixture was extracted with CH2Cl2, dried over MgSO4, and the solvent was removed under vacuum. The residue was purified by column chromatography, eluting with CH2Cl2 / petroleum ether (1.5:1, v / v). Recrystallization from ethyl acetate and ethanol gave a bright yellow solid TPE-TP4 (274.9 mg, 85%). In this example, the structure of the target compound TPE-TP4 was identified by 1H NMR, 13C NMR, high-resolution mass spectrometry, and elemental analysis: 1 1H NMR (CDCl3, TMS, 600 MHz) δ (ppm): 8.41 (d, J J = 3.0 Hz, 1H), 7.93 (dd, J J = 16.3, 2.6 Hz, 2H), 7.84 (d, J J = 2.6 Hz, 3H), 7.62 (dd, J J = 8.1, 3.2 Hz, 2H), 7.40 (dd, J J = 8.1, 3.2 Hz, 2H), 4.25 - 4.20 (m, 6H), 4.17 - 4.14 (m, 2H), 4.12 - 4.11 (m, 2H), 1.96 - 1.91 (m, 6H), 1.82 - 1.74 (m, 4H), 1.59 - 1.38 (m, 22H), 1.29 - 1.28 (m, 4H), 1.21 - 1.20 (m, 4H), 0.95 - 0.91 (m, 9H), 0.86 - 0.84 (m, 3H), 0.80 - 0.77 (m, 3H). 1313C NMR (CDCl3, 151 MHz) δ (ppm): 155.06, 149.72, 149.25, 148.79, 142.72, 140.94, 136.79, 131.26, 130.40, 129.39, 129.19, 125.15, 124.77, 124.06, 123.21, 123.11, 123.05, 107.85, 107.53, 107.00, 106.79, 105.28, 69.81, 69.52, 69.40, 68.74, 31.67, 31.60, 31.36, 29.43, 29.41, 29.37, 29.30, 29.16, 25.84, 25.82, 25.79, 25.68, 22.64, 22.58, 14.04, 14.00, 13.97. HRMS (MALDI): [M] + calculated for C 218 H 300 O 20 , m / z: 3240.2525 (100.0%), 3239.2492 (85.2%), 3241.2559 (59.0%), 3242.2592 (44.9%), 3238.2458 (36.1%); found, 3240.2521, 3239.2551, 3241.2540, 3242.2582, 3238.2602. Elemental analysis: calculated for C 218 H 300 O 20 (3240.78), C 80.80%, H 9.33%; found, C 80.92%, H 9.66%. In terms of performance, its good thermal stability, typical liquid crystal texture, wide liquid crystal phase transition range and mesomorphic intermediate phase stacking mode were tested by polarized light microscopy (POM) with a hot stage, differential scanning calorimetry (DSC), small angle / wide angle X-ray scattering (S / WAXS) techniques, and its ultraviolet-visible absorption spectrum, fluorescence emission spectrum and aggregation-induced effect in solution were tested to explore its application as an organic thin film material in ultraviolet-visible organic photodetectors.

[0059] Example 9: Synthesis of the target compound TPE-ThTP4 (tetraphenylethylene-thiophene-tetracene tetramer compound) A preparation method of a tetraphenylethylene-thiophene-triphenylene tetramer compound TPE-ThTP4, and its synthesis and steps are as follows: Under argon, 1,1,2,2-tetrakis(4-bromophenyl)ethylene (69.1 mg, 0.11 mmol), M7 (500.0 mg, 0.53 mmol), K2CO3 (294.9 mg, 2.13 mmol) and Pd(PPh3)4 (49.3 mg, 0.04 mmol) were mixed and stirred in a H2O / THF (3.0 mL / 9.0 mL) solvent. The mixture was heated to 70 °C with stirring for 48 h. After cooling, the mixture was extracted with CH2Cl2, dried over MgSO4, and the solvent was removed under vacuum. The residue was purified by column chromatography, eluting with CH2Cl2 / petroleum ether (2:1, v / v). Recrystallization from ethyl acetate and ethanol gave a dark yellow solid TPE-ThTP4 (205.6 mg, 54%). In this example, the structure of the target compound TPE-ThTP4 was identified by 1H NMR, 13C NMR, high-resolution mass spectrometry, and elemental analysis: 1 1H NMR (CDCl3, TMS, 600 MHz) δ (ppm): 8.59 (s, 1H), 7.86 (s, 1H), 7.77 (s, 1H), 7.74 (s, 2H), 7.70 (s, 1H), 7.66 (d, J J = 3.6 Hz, 1H), 7.56 (d, J J = 8.0 Hz, 2H), 7.38 (d, J J = 3.6 Hz, 1H), 7.23 (d, J J = 8.0 Hz, 2H), 4.26 - 4.18 (m, 10H), 2.01 - 1.90 (m, 10H), 1.64 - 1.54 (m, 10H), 1.40 - 1.34 (m, 20H), 0.95 - 0.88 (m, 15H). 1313C NMR (CDCl3, 151 MHz) δ (ppm): 153.83, 149.68, 149.14, 148.74, 148.63, 143.38, 142.74, 140.32, 139.46, 132.95, 132.14, 129.10, 126.77, 124.89, 124.74, 123.71, 123.16, 123.01, 122.91, 122.67, 122.57, 122.40, 107.59, 107.30, 106.77, 106.52, 104.27, 69.72, 69.69, 69.39, 69.26, 68.82, 31.73, 31.71, 29.46, 29.45, 29.42, 29.37, 29.31, 26.09, 25.88, 25.86, 22.66, 14.05. HRMS (MALDI): [M] + calcd for C 234 H 308 O 20 S4, m / z: 3568.2034(100.0%), 3569.2067 (83.6%), 3567.2000 (79.4%), 3570.2101 (36.5%), 3566.1967(31.4%); found, 3568.2025, 3569.2040, 3567.2013, 3570.2081, 3566.2051.Elemental analysis: calculated for C 234 H 308 O 20 S4 (3569.26), C 78.74%, H 8.70%, S 3.59%; found, C 78.51%, H 8.86%, S 3.90%. In terms of performance, its good thermal stability, typical liquid crystal texture, wide liquid crystal phase transition range and mesomorphic intermediate phase stacking mode were tested by techniques such as polarized light microscopy (POM) with a hot stage, differential scanning calorimetry (DSC), small angle / wide angle X-ray scattering (S / WAXS). And its ultraviolet-visible absorption spectrum, fluorescence emission spectrum, aggregation-induced effect and organogel properties in solution were tested to explore its application as an organic thin film material in ultraviolet-visible organic photodetectors.

Claims

1. A method for preparing pentahexyloxy-substituted monobromobiphenylenes, characterized in that It includes the following steps: Step 1: Preparation of precursor M1: At room temperature, a solution of FeCl3 (26.15 g, 161.24 mmol) dissolved in CH3NO2 (30.0 mL) was added to a solution of 4-bromo-1,2-dimethoxybenzene (10.00 g, 46.07 mmol) stirred in dry CH2Cl2 (100.0 mL); after 1 hour, cold methanol (20.0 mL) and water (20.0 mL) were added to quench the reaction; it was extracted with CH2Cl2 and purified by silica gel column chromatography (petroleum ether / CH2Cl2, 1:3, v / v), and recrystallized from petroleum ether to obtain white solid M1 (6.97 g, 70%); Step 2: Preparation of precursor M2: In a single-necked RBF tube equipped with a stopcock, at -78 °C, M1 (18.00 g, 41.66 mmol) was dissolved in THF (150.0 mL), and 2.5 M n -BuLi (49.98 mL, 124.97 mmol) was added dropwise under an argon atmosphere; after stirring at -78 °C for 30 minutes, the solution was slowly warmed to room temperature and stirred for another 3 hours; then methanol (20.0 mL) was added to quench the solution, and the solution was extracted with ethyl acetate. It was purified by silica gel column chromatography (pure CH2Cl2) and recrystallized from petroleum ether to obtain white solid M2 (9.38 g, 82%); Step 3: Preparation of precursor M3: At room temperature, M2 (9.00 g, 32.81 mmol) and 2-bromoanisole (9.20 g, 49.21 mmol) were stirred in dry CH2Cl2 (100.0 mL), and then a solution of FeCl3 (31.93 g, 196.85 mmol) dissolved in CH3NO2 (20.0 mL) was added to the above solution; after 2 hours, the solution was poured into ice water (30.0 mL)-methanol (30.0 mL), and stirred at room temperature for another 10 minutes to obtain a precipitated product; subsequently, the mixture was filtered through a Buchner funnel, and the residue was purified by silica gel column chromatography (pure CH2Cl2) and recrystallized from ethanol to give off-white powder M3 (11.16 g, 74%); Step 4: Preparation of precursor M4: Under argon, M3 (4.40 g, 9.62 mmol) was added to a Schlenk reaction tube and stirred with dry CH2Cl2 (20.0 mL); the above mixture was placed at -78 °C, then BBr3 (6.49 mL, 67.35 mmol) was injected into the reaction system and stirred overnight; then, the solution was poured into ice water (200.0 mL) and stirred until the mixture returned to room temperature; subsequently, the mixture was filtered through a Buchner funnel (filled with double-layer filter paper), and the residue was dried under argon to obtain a purple-black solid, 11-bromotriphen-2,3,6,7,10-pentanol; immediately, in a 250 mL round-bottom flask, 11-bromotriphenyl-2,3,6,7,10-pentanol, n-hexyl bromide (9.53 g, 57.73 mmol), K2CO3 (15.96 g, 115.46 mmol), zinc powder (314.6 mg, 4.81 mmol) and KI (798.6 mg, 4.8 mmol) were added, and the solvent DMF (70.0 mL) was added; the system was heated to 90 °C and stirred for 24 hours; then, the hot mixture was immediately poured into ice water in a 500 mL beaker, and dilute hydrochloric acid was added to the solution until the system was acidic, filtered through a Buchner funnel (filled with double-layer filter paper), and the solvent was evaporated; the product was purified by silica gel column chromatography (CH2Cl2 / petroleum ether, 1:2, v / v) and recrystallized from ethyl acetate and ethanol to obtain a white solid M4 (5.61 g, 72%).

2. A method for preparing a propeller-shaped tetraphenylethylene-tetracene tetramer discotic liquid crystal, characterized in that It includes the following steps: Step 1: Preparation of intermediate M5: In a dry flask under argon atmosphere, add M4 (2.6 g, 3.22 mmol), bis(pinacolato)diboron (1.80 g, 7.08 mmol), Pd(dppf)Cl2·CH2Cl2 (131.4 mg, 0.16 mmol) and CH3COOK (947.4 mg, 9.65 mmol); after adding 1,4-dioxane (70.0 mL), stir the reactants at 90 °C for 24 hours; then, cool the reaction mixture to room temperature and extract with CH2Cl2; dry the combined organic layers over anhydrous MgSO4, evaporate, and purify the residue by column chromatography (eluent petroleum ether / CH2Cl2, 1:3, v / v); recrystallize from ethyl acetate and ethanol to obtain white solid M5 (1.92 g, 70%); Step 2: Preparation of target compound tetraphenylethylene-tetraphenylporphyrin tetrameric discotic liquid crystal TPE-TP4: In an argon atmosphere, 1,1,2,2-tetrakis(4-bromophenyl)ethylene (64.8 mg, 0.10 mmol), M5 (527.5 mg, 0.50 mmol), K2CO3 (276.4 mg, 2.00 mmol) and Pd(PPh3)4 (34.7 mg, 0.03 mmol) were mixed and stirred in a H2O / THF (3.0 mL / 9.0 mL) solvent; the mixture was heated to 70 °C with stirring for 48 h; after cooling, the mixture was extracted with CH2Cl2, dried over MgSO4, and the solvent was removed under vacuum; the residue was purified by column chromatography, eluting with CH2Cl2 / petroleum ether (1.5:1, v / v); recrystallization from ethyl acetate and ethanol gave a bright yellow solid TPE-TP4 (274.9 mg, 85%).

3. A method for preparing a propeller-shaped tetraphenylethylene-thiophene-triphenylene tetrameric discotic liquid crystal, characterized in that It includes the following steps: Step 1: Preparation of intermediate M6: In an argon atmosphere, M4 (1.00 g, 1.24 mmol), 2-thiopheneboronic acid (237.5 mg, 1.86 mmol), K2CO3 (855.2 mg, 6.19 mmol) and Pd(PPh3)4 (143.0 mg, 0.12 mmol) were added to a reaction tube; degassed water (5.0 mL) and THF (15.0 mL) were injected into the reaction mixture; the mixture was stirred at 70 °C for 24 hours; then, it was cooled, extracted with CH2Cl2 and dried over MgSO4; the organic solvents were removed by distillation, and the residue was purified by silica gel column chromatography (petroleum ether / CH2Cl2, 2:1, v / v); recrystallization from ethyl acetate and ethanol gave white solid M6 (926.4 mg, 92%); Step 2: Preparation of intermediate M7: In a reaction tube, M6 (811.0 mg, 1.00 mmol) was dissolved in THF (20.0 mL) at -78 °C, and 2.5 M n -BuLi (0.60 mL, 1.50 mmol) was added dropwise under an argon atmosphere; the mixture was stirred at -78 °C for another 2 hours; then 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (372.0 mg, 2.00 mmol) was rapidly injected into the solution; after stirring at -78 °C for 30 minutes, the solution was stirred at room temperature overnight; the reaction mixture was extracted with CH2Cl2, the combined organic layers were washed with brine, and dried over anhydrous MgSO4, and evaporated under reduced pressure; the residue was purified by silica gel column chromatography using petroleum ether / CH2Cl2 as the eluent (1:3, v / v) and recrystallized from ethyl acetate and ethanol to give a gray-green solid M7 (534.1 mg, 57%); Step 3: Preparation of target compound tetraphenylethylene-thiophene-tetraphenylporphyrin tetrameric discotic liquid crystal TPE-ThTP4: Under argon, 1,1,2,2 - tetra(4 - bromophenyl)ethylene (69.1 mg, 0.11 mmol), M7 (500.0 mg, 0.53 mmol), K2CO3 (294.9 mg, 2.13 mmol) and Pd(PPh3)4 (49.3 mg, 0.04 mmol) were mixed and stirred in a H2O / THF (3.0 mL / 9.0 mL) solvent; the mixture was heated to 70 °C with stirring for 48 h; after cooling, the mixture was extracted with CH2Cl2, dried over MgSO4, and the solvent was removed under vacuum; the residue was purified by column chromatography, eluting with CH2Cl2 / petroleum ether (2:1, v / v); recrystallization from ethyl acetate and ethanol gave a dark yellow solid TPE - ThTP4 (205.6 mg, 54%).

4. Use of the tetrameric discotic liquid crystal target compounds TPE-TP4 and TPE-ThTP4 described in claims 2 and 3 as organic liquid crystal materials, liquid crystal semiconductor materials and their composites in organic thin film electronic devices.

5. Without departing from the concept of the present invention, those skilled in the art can make improvements to the preparation method and the instruments used within the scope of the claims, and these improvements should also be regarded as the protection scope of the present invention.

Images