CN104877666A - Luminescent material having aggregation-induced emission, method of making and application thereof - Google Patents

Abstract

The luminescent material of the present invention has aggregation-induced/enhanced luminescence (AIE/AEE) characteristics, and the maximum absorption wavelength is red-shifted to the visible region, so that this type of luminescent material has potential applications in the fields of biology and optoelectronics; it has excellent optical waveguide properties, The optical loss is as low as 0.100dB/μm, which can be used to prepare optical waveguide materials and organic light-emitting diode devices; this type of material has the characteristics of mechanochromism due to the AIE characteristics, and the mechanochromism phenomenon is reversible. In terms of smart materials have potential applications.

Description

Luminescent material with aggregation-induced luminescent properties, preparation method and application thereof

technical field

The invention relates to a series of organic luminescent materials, in particular to a solid-state luminescent material with characteristics of aggregation-induced luminescence or luminescence enhancement (AIE/AEE).

Background technique

With the development of organic optoelectronics, new organic light-emitting semiconductor functional materials used in solid state or aggregated state, due to their high sensitivity, good device flexibility, low cost, small device size, and large area compared with traditional inorganic semiconductor materials Due to the advantages of preparation and easy integration, more and more attention has been paid (Chem. Phys. Lett., 1974, 29, 277, Chem. Rev. 2007, 107, 1011). In addition to organic optoelectronic devices, organic light-emitting materials are used in information storage (J.Mater.Chem.C,2013,1,3376; Chem.Soc.Rev.,2013,42,857; Adv.Mater.,2013,25,378; Chem.Soc. Rev., 2013, 42, 8895.) and biological sciences (Chem. Rev., 2013, 113, 192; Chem. Sci., 2012, 3, 984.) have also shown a wide range of applications.

However, traditional organic light-emitting materials are always accompanied by an inevitable phenomenon: aggregation-caused quenching (ACQ), and traditional fluorescent materials usually contain large π-electron conjugated structures, which are mainly used to generate fluorescence. In the state of molecular dissolution, the solution of the fluorescent dye shows strong fluorescence, but in the state of concentrated solution, aggregated state or solid state, the intermolecular interaction is enhanced, energy transfer occurs, and exciplexes or excimer associations are formed, which will consume Excited state energy, thus greatly reducing the probability of fluorescence emission, which is the well-known ACQ phenomenon. However, in modern technology applications, in most cases, fluorescent materials need to be processed into an aggregated state, and the ACQ problem is inevitable. Various chemical (Chem.Commun., 2008, 1501; Chem.Commun., 2008, 217.), physical, and engineering methods and processes have been developed (Langmuir, 2006, 22, 4799; Macromolecules 2003, 36, 5285) to weaken the ACQ effect. However, these attempts have only achieved minor success. The main difficulty is that the formation of aggregates in the condensed phase is an intrinsic process, so it is urgent to develop materials and systems that maintain strong luminescence in the aggregated state.

In 2001, the researchers of the present invention synthesized 1,1-dimethyl-2,3,4,5-tetraphenylsilole (DMTPS) compound, whose aggregated state plays a beneficial role in fluorescence emission rather than destruction Sexual effect (Chem.Commun.2001,1740.), researchers also observed a novel phenomenon and dubbed it "aggregation-induced emission" (aggregation-induced emission, AIE), in which molecules that do not emit light in the solution state pass through aggregates Formed and induced to emit light: a series of helical non-luminescent molecules, such as hexaphenylsilole (HPS) and tetraphenylethylene (tetraphenylethene, TPE), are induced to emit strong fluorescence by forming aggregates (J.Mater Chem.2001, 11, 2974; Chem.Commun.2009, 4332; Appl.Phys.Lett.2007, 91, 011111.), after which researchers found many molecules with this property. In addition, through a series of experimental designs and theoretical calculations, the researchers confirmed that restricted intramolecular motion (RIM) is the main cause of the AIE effect (J.Phys.Chem.B2005, 109, 10061; J.Am.Chem. Soc.2005, 127, 6335.).

So far, most AIE emitters prepared can only emit blue light and green light. Compared with blue light-emitting materials, the development and research of yellow light and red light materials are relatively lagging behind. In organic integrated circuits, yellow light and red light are relatively lagging behind. Red light materials are an essential component; also for biological imaging applications, those dyed molecules that emit long wavelengths are more preferred, so that they will not be interfered by the autofluorescence of biological tissues, and the damage to the tissue by the excitation light source will also be reduced. (Chem. Mater., 2012, 24, 812). For the preparation of yellow and green light materials, the method in the prior art is to extend the π-conjugated structure of the molecule and then narrow the energy band gap to facilitate electronic transitions, but the disadvantage of this method is that the synthesis process is complicated and the synthesis workload is large. , Enhanced intermolecular interactions, which easily lead to quenching of induced luminescence, susceptibility to photooxidation, and reduced product solubility.

Contents of the invention

The object of the present invention is to provide a luminescent material with aggregation-induced luminescent properties and its preparation method and application, so as to solve the problem of limited application of luminescent materials with aggregation-induced luminescent properties in the prior art.

The technical solution adopted by the present invention to solve the technical problem is: a luminescent material with aggregation-induced luminescent properties, which contains a group selected from any of the following structural formulas:

Wherein, R ¹ , R ² and R ³ are respectively selected from -H, linear or branched alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, alkoxy, aryloxy, carboxy , isothiocyanate group, azido group, alkyl azido group, alkylamino group, chloroalkyl group, bromoalkyl group, iodoalkyl group, ester group, R ¹ , R ² and R ³ can also Respectively selected from the following structural formulas:

or Wherein Y is O, S or Se; R ₁ and R ₂ are -H, linear or branched alkyl respectively, R ₃ and R ₄ are linear or branched alkyl or alkoxy respectively;

In structural formulas I and II, at least one R ¹ , R ² or R ³ is contained respectively; Y is O, S or Se; R ₁ and R ₂ are linear or branched alkyl groups respectively; R ₃ and R ₄ are respectively is a linear or branched alkyl or alkoxy group;

The tetraphenylethylene units in formulas I and II include at least one and are linked by a C-C single bond, a C=C double bond or a C≡C triple bond.

In the luminescent material with aggregation-induced luminescent properties of the present invention, R ¹ , R ² and R ³ are all -H; Y is O.

In the luminescent material with aggregation-induced luminescent properties of the present invention, in structural formula I, R ₁ and R ₂ are respectively selected from -H or alkyl and R ₁ and R ₂ are the same group; in structural formula II, R ₁ and R2 are _both -H, _R3 and _R4 are respectively selected from alkyl or alkoxy and _R3 and _R4 are the same group.

In the luminescent material with aggregation-induced luminescent properties of the present invention, in structural formula I, R ₁ and R ₂ are both -H or both are -CH ₃ groups; in structural formula II, R ₃ and R ₄ are both - _{CH3 or -OC6H13} group.

The present invention also provides the application of the above-mentioned light-emitting material with aggregation-induced light-emitting characteristics in the preparation of optical waveguide materials.

The present invention also provides the application of the above-mentioned light-emitting material with aggregation-induced light-emitting characteristics in the preparation of an organic light-emitting diode device.

The present invention also provides the application of the above-mentioned luminescent material with aggregation-induced luminescent properties in the preparation of fluorescent dyes for intracellular imaging.

The present invention also provides a method for preparing the above-mentioned luminescent material with aggregation-induced luminescent properties, comprising the following steps: heating and refluxing the tetraphenylethylene derivatives and barbituric acid compounds as reaction initiators in an organic alcohol solvent, forming a precipitate, filtering the precipitate, washing the filtered product with an organic solvent, and drying in vacuum to obtain a luminescent material;

Wherein the structural formula of the tetraphenylethylene derivative in the reaction starter is:

or

Wherein, R ¹ , R ² and R ³ are respectively selected from -H, linear or branched alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, alkoxy, aryloxy, carboxy , isothiocyanate group, azido group, alkyl azido group, alkylamino group, chloroalkyl group, bromoalkyl group, iodoalkyl group, ester group, R ¹ , R ² and R ³ can also Respectively selected from the following structural formulas:

or Wherein Y is O, S or Se; R ₁ and R ₂ are -H, linear or branched alkyl respectively, R ₃ and R ₄ are linear or branched alkyl or alkoxy respectively;

In the structural formula of tetraphenylethylene derivatives in the reaction starting material, there are at least one R ¹ , R ² or R ³ respectively; the tetraphenylethylene unit includes at least one, and through CC single bond, C=C double bond Or a C≡C triple bond linkage.

In the preparation method of the present invention, the barbituric acid compound in the reaction starting material is barbituric acid or N,N-dimethylbarbituric acid; the organic alcohol solvent is methanol or ethanol; The organic solvent is selected from at least one of methanol, ethanol, and ether; the precipitate can be filtered while it is hot or cooled to room temperature to obtain a solid.

In the preparation method of the present invention, it also includes the step of adding concentrated sulfuric acid as a catalyst during the heating and reflux reaction; and the step of recrystallizing the filtered product with diethyl ether and hexane after washing the filtered product.

It should be noted that the alkyl group can be straight-chain or branched, with 1-10 carbon atoms in the chain, preferably 2-6 carbon atoms; the cycloalkane The group refers to a non-aromatic monocyclic or polycyclic ring containing 3-10 carbon atoms; the heteroalkyl group refers to at least one carbon atom in the alkyl group is replaced by a heteroatom; the heterocycloalkyl group refers to a group of 3-7 rings At least one ring in the cycloalkyl group is a heteroatom, which is selected from O, N, S, Si and B; the aryl group preferably contains 6-18 carbon atoms, such as phenyl, naphthyl, anthracenyl, tetracene Group, pyrene group; in the aryl group containing 5-10 rings, at least one ring is a heteroatom, and the heteroatom is selected from O, N, S, Si and B.

The implementation of the luminescent material with aggregation-induced luminescent properties and its application of the present invention has the following beneficial effects: the luminescent material of the present invention has aggregation-induced/enhanced luminescent properties (aggregation-induced/enhanced emission, AIE/AEE), and is dispersed in an aqueous medium It shows AIE/AEE characteristics; its absorption red shifts to the visible region, thereby improving the application possibility of luminescent materials in biology and optoelectronics _; it can form nano Particles, the nanoparticles can enter the cells after protein coating; in the process of grinding-fumigation and grinding-heating, due to the change of molecular shape between crystal and amorphous, the luminous color changes reversibly; without adding melamine and adding Under the condition of melamine, nanospheres, nanorods and nanotubes can be self-assembled in different solvents; it has excellent optical waveguide properties, and the optical loss coefficient is as low as 0.137dB/μm, which can be used to prepare optical waveguide materials; Good solid-state light-emitting properties can also be used to prepare organic light-emitting diode devices.

Description of drawings

Figure 1 is a synthetic route diagram of TPE-s-Bar, TPE-Bar, TPE-MPh-Bar and TPE-HPh-Bar;

Figure 2 is the ORTEP diagram of TPE-s-Bar;

Figure 3A is the photoluminescence (PL) spectrum of TPE-s-Bar in THF/H ₂ O solvents with different water contents (vol%), and the inset is the I/I ₀ of TPE-s-Bar in the system The correlation curve between water content, I ₀ is the maximum PL intensity of TPE-s-Bar in pure THF, the concentration is 10μM, and the excitation wavelength is 420nm;

Figure 3B is the photoluminescence (PL) spectra of TPE-Bar in THF/H ₂ O solvents with different water contents (vol%), where the inset is the I/I ₀ of TPE-Bar and the difference between different water contents Correlation curve, I ₀ = maximum PL intensity of TPE-Bar in pure THF, the concentration is 10μM, and the excitation wavelength is 420nm;

Figure 3C is the photoluminescence (PL) spectra of TPE-MPh-Bar in THF/H ₂ O solvents with different water content (vol%), and the inset is the I/I ₀ of TPE-MPh-Bar with different water The correlation curve between the contents, I ₀ = the maximum PL intensity of TPE-MPh-Bar in pure THF, the concentration is 10μM, and the excitation wavelength is 410nm;

Figure 4A is the photoluminescence (PL) spectrum of TPE-HPh-Bar in THF/H ₂ O solvents with different water contents (f _w ), where the concentration is 10 μM and the excitation wavelength is 447 nm;

Figure 4B is the correlation curve of the relative PL intensity I/I ₀ of TPE-HPh-Bar and THF/H ₂ O composition, I ₀ is the emission intensity (emission intensity) of TPE-MPh-Bar in pure THF, the illustration is Fluorescence photographs of solutions formed by TPE-HPh-Bar in THF/H ₂ O systems with water contents of 0 vol% and 95 vol% respectively under ultraviolet light irradiation;

Fig. 5A is the change figure of emission spectrum of TPE-s-Bar crystal in grinding-solvent fumigation process;

Figure 5B is a repeated conversion diagram of the solid-state luminescence of TPE-s-Bar through repeated grinding-solvent fumigation cycles;

Fig. 6A is the change diagram of emission spectrum of TPE-Bar in grinding-solvent fumigation process;

Figure 6B is a repeated conversion diagram of the solid-state fluorescence of TPE-Bar through repeated grinding-solvent fumigation cycles;

Fig. 7A is the change diagram of emission spectrum of TPE-MPh-Bar in grinding-solvent fumigation process;

Figure 7B is a repeated conversion diagram of the solid-state fluorescence of TPE-MPh-Bar by repeated grinding-solvent fumigation cycles;

Figure 8A is the XRD diffraction pattern of the heating rate of TPE-s-Bar in different aggregation states at 10°C min ^-1 ;

Figure 8B is the DSC thermogram of the heating rate of TPE-s-Bar in different aggregation states at 10°C min ^-1 ;

Figure 9A is the XRD diffraction pattern of the heating rate of TPE-Bar in different aggregation states at 10°C min ^-1 ;

Figure 9B is the DSC thermogram of the heating rate of TPE-Bar in different aggregation states at 10°C min ^-1 ;

Figure 10A is a SEM imaging image of microspheres and nanospheres formed after a 100 μM TPE-HPh-Bar solution is slowly volatilized in acetonitrile;

Figure 10B is a SEM image of microspheres and nanospheres formed after the TPE-HPh-Bar solution with a concentration of 10 μM is slowly volatilized in acetonitrile;

Figure 10C is a SEM image of nanospheres formed by slow solvent volatilization of a TPE-HPh-Bar solution with a concentration of 50 μM in acetonitrile/ethanol (1:1 v/v) at room temperature;

Figure 10D is a SEM image of nanospheres formed by slow solvent volatilization of a TPE-HPh-Bar solution with a concentration of 50 μM in acetonitrile/water (1:1 v/v) at room temperature;

Figure 11A shows the microspheres and nanospheres formed by the slow evaporation of solvent in 100 μM concentration of TPE-HPh-Bar solution in DMSO/ethanol (1:1v/v) at room temperature under the condition of adding 10 equivalents of melamine. SEM image, scale bar: 5 μm;

Figure 11B shows the microspheres and nanospheres formed by the slow evaporation of the solvent in DMSO/ethanol (1:1v/v) at room temperature with the addition of 10 equivalents of melamine in a TPE-HPh-Bar solution of 100 μM SEM image of SEM image, scale bar: 1 μm;

Figure 11C shows microspheres and nanospheres formed by slow evaporation of solvent in 100 μM TPE-HPh-Bar solution in DMSO/ethanol (1:1 v/v) at room temperature with the addition of 25 equivalents of melamine The SEM image, scale bar: 2 μm;

Figure 11D shows microspheres and nanospheres formed by slow solvent volatilization of 100 μM TPE-HPh-Bar solution in DMSO/ethanol (1:1 v/v) at room temperature with the addition of 25 equivalents of melamine SEM image of SEM image, scale bar: 1 μm;

Figure 12A is a microscopic fluorescence imaging photo of TPE-s-Bar microrods excited by a concentrated UV laser (400nm) at seven different positions;

Figure 12B is the PL spectrum of the microrod marked with a-g at the end of the TPE-s-Bar microrod recorded in 12A;

Figure 12C is a correlation graph of the TPE-s-Bar peak intensity and the distance between the excitation position and the light-emitting end;

Figure 13A is a microscopic fluorescence imaging photo of TPE-HPh-Bar microrods excited by a concentrated UV laser (400nm) at seven different positions;

Figure 13B is the PL spectrum of the microrod marked with a-g at the right end of the rod recorded on the TPE-HPh-Bar microrod in Figure 13A;

Figure 13C is a correlation graph of TPE-HPh-Bar peak intensity and the distance between the excitation position and the light-emitting end;

Figure 14 is a SEM image of TPE-HPh-Bar nanoparticles encapsulated by bovine serum albumin, scale bar: 1 μm.

Detailed ways

The luminescent material with aggregation-induced luminescent properties and its application and preparation method of the present invention will be further described in conjunction with the accompanying drawings and examples:

The specific preparation process of the new luminescent material with aggregation-induced luminescent properties of the present invention is illustrated by the following examples. It should be noted that the luminescent materials prepared below are only one or more of the luminescent materials represented by each of the structural formulas I-II protected in the claims, but the luminescent materials protected in the present invention are not limited thereto.

Wherein the synthetic process of embodiment 1-4 refers to the synthetic route shown in Figure 1.

Embodiment 1: Synthesis of TPE-Bar

Structural formula:

Chinese chemical name: 5-(4-(1,2,2-triphenylethenyl)benzylidene)pyrimidine-2,4,6(1H,3H,5H)-trione

English chemical formula: 5-(4-(1,2,2-triphenylvinyl)benzylidene)pyrimidine-2,4,6(1H,3H,5H)-trione

Synthetic method: Mix 4-(1,2,2-triphenylvinyl)benzaldehyde 1 (500mg, 1.39mmol) and barbituric acid 3 (186mg, 1.46mmol) in a mixed solvent of methanol 20mL and THF 5mL After reflux for 24 hours, a bright yellow precipitate was formed. After the reaction mixture was cooled to room temperature, the formed bright yellow precipitate was filtered. The filtered solid was washed three times with ethanol and ether, respectively, and dried in vacuo to obtain 390 mg of the product with a yield of 61%. ¹ H-NMR (400MHz,d ⁶ -DMSO): δ11.48(s,1H),11.33(s,1H),8.26(s,1H),8.11(d,J=8.8Hz,2H),7.32- 7.23 (m, 9H), 7.17 (d, J=8.4Hz, 2H), 7.15-7.09 (m, 6H); ¹³ C-NMR (100MHz, d ⁶ -DMSO): 163.44, 161.67, 153.99, 150.11, 147.83 , 142.77, 142.70, 142.56, 142.23, 139.77, 133.49, 130.68, 130.62, 130.57, 130.40, 128.01, 127.98, 127.81, 127.00, 126.80, _118.32 ; HR-MS (MALDI-TOF) elemental analysis value: 4 H ₂₂ N ₂ O ₃ : C, 79.13; H, 4.71; N, 5.95: Found: C, 79.11; H, 4.732; N, 5.88.

Embodiment 2: Synthesis of TPE-s-Bar

Structural formula:

Chinese chemical name: 1,3-dimethyl-5-(4-(1,2,2-triphenylethenyl)benzylidene)pyrimidine-2,4,6(1H,3H,5H)- Triketone

English chemical formula: 1,3-dimethyl-5-(4-(1,2,2-triphenylvinyl)benzylidene)pyrimidine-2,4,6(1H,3H,5H)-trione

Synthetic method: Add 4-(1,2,2-triphenylvinyl)benzaldehyde 1 (500mg, 1.39mmol) and N,N-dimethylbarbituric acid 2 (227mg, 1.46mmol) to the mixture A drop of concentrated sulfuric acid was used as a catalyst, and refluxed in ethanol (20mL) for 24h to form an orange-yellow precipitate. After the reaction mixture was cooled to room temperature, the formed orange-yellow precipitate was filtered. The filtered solid was rinsed three times with ethanol and ether, and dried in vacuo. 480 mg of the product was obtained with a yield of 70%. HR-MS (MALDI-TOF) C ₃₃ H ₂₆ N ₂ O ₃ theoretical value 498.1943; measured value: 498.1941; ¹ H-NMR (400MHz, CDCl ₃ ): δ8.44(s, 1H), 7.96(d, 2H ),7.14-7.10(m,11H),7.06-7.01(m,6H),3.40(s,3H),3.36(s,3H); ¹³ C-NMR(100MHz,CDCl ₃ ):δ161.72,159.57,157.86 ,150.27,148.70,142.24,142.12,142.04,141.90,138.94,133.04,130.34,130.33,130.29,130.24,129.52,126.91,126.88,126.66,126.08,125.83,125.80,115.30,28.07,27.39。

Embodiment 3: Synthesis of TPE-HPh-Bar

Structural formula:

The steps include: (1) synthesizing TPE-HPh

Chinese chemical name: 2,5-dihexyloxy-4-((4-(1,2,2-triphenylethenyl)phenyl)ethynyl)benzaldehyde

English chemical formula: 2,5-dihexyloxy-4-((4-(1,2,2-triphenylvinyl)phenyl)ethynyl)benzaldehyde

Synthetic method: Add 2-(4-ethynylphenyl)-1,1,2-triphenylethenyl 4 (1g, 2.81mmol), 4-bromo-2,5- Dihexyloxybenzaldehyde 6 (1.03g, 2.68mmol), bis(triphenylphosphine)palladium(II) chloride (Pd(PPh ₃ ) ₂ Cl ₂ ) (0.089g, 0.126mmol), iodide Copper (0.024g, 0.121mmol) and triphenylphosphine (0.066g, 0.251mmol), the above-mentioned mixture was vacuumized and gas exchanged three times with nitrogen to completely remove oxygen, and 30mL of newly distilled THF and Anhydrous and degassed triethylamine 10mL, reflux reaction at 70°C for 8h to form a precipitate, after cooling to room temperature, filter out the formed precipitate, remove the solvent by rotary evaporation, and peroxide the residue after removing the solvent A silica column was eluted with n-hexane/dichloromethane (4:1 v/v) to obtain 1.3 g of an orange-yellow solid product with a yield of 73.4%. MS: 660.3 (M ⁺ ); ¹ H NMR (400MHz, CDCl ₃ ) δ10.43 (s, 1H), 7.30 (d, 2H), 7.27 (s, 1H), 7.15 (s, 1H), 7.13-7.08 (m,8H),7.06-6.81(m,9H),4.05-4.00(m,4H),1.84-1.79(m,4H),1.50-1.46(m,4H),1.37-1.31(m,8H) ,0.93-0.85(m,6H).

(2) Synthesis of TPE-HPh-Bar

Chinese chemical name: 5-(2,5-Dihexyloxy-4-((4-(1,2,2-triphenylethenyl)phenyl)ethynyl)benzylidene)pyrimidine-2, 4,6(1H,3H,5H)-trione

English chemical formula: 5-(2,5-dihexyloxy-4-((4-(1,2,2-triphenylvinyl)phenyl)ethynyl)benzylidene)pyrimidine-2,4,6(1H,3H,5H)-trione

Synthetic method: add TPE-HPh (500mg, 0.758mmol) and barbituric acid 3 (106mg, 0.828mmol) into a round bottom flask, then add methanol 40mL and THF 5mL, stir the above mixture in a nitrogen atmosphere and heat to reflux 24h, a red precipitate was formed, filtered while it was hot, and the obtained filtered product was washed three times with methanol, then the obtained red solid was dissolved in ether, an appropriate amount of hexane was added, and then recrystallized to obtain crystalline product 0.356g, yield 61 %. ¹ H NMR (400MHz, CDCl ₃ ), δ9.06(s, 1H), 8.30(s, 1H), 8.18(s, 1H), 8.11(s, 1H), 7.29(d, ² J＝8.4Hz, 2H),7.13-7.08(m,9H),7.05-7.01(m,8H),6.98(s,1H),4.06-4.02(m,4H),1.86-1.81(m,4H),1.58-1.43( m,4H),1.37-1.29(m,8H),0.92-0.84(m,6H); ¹³ CNMR(400MHz,CDCl ₃ ),δ(TMS,ppm):162.99,160.92,155.18,154.56,152.65,148.80 ,144.85,143.57,143.51,143.41,142.10,140.33,131.57,131.52,131.47,131.43,131.36,127.98,127.93,127.83,126.88,126.80,122.07,121.84,120.85,116.81,115.61,114.82,98.77,86.59,69.73 , 69.61, 31.73, 31.60, 29.31, 29.17, 25.89, 25.78, 22.75, 22.71, 14.18, 14.14; HRMS (MALDI-TOF) C ₅₁ H ₅₀ N ₂ O ₅ theoretical value 770.3720; measured value 770.3722. Elemental analysis theoretical value C ₅₁ H ₅₀ N ₂ O ₅ : C, 79.45; H, 6.54; N, 3.63; Found: C, 79.60; H, 6.606; N, 3.59.

Embodiment 4: Synthesis of TPE-MPh-Bar

Structural formula:

The steps include: (1) synthesizing TPE-MPh

Chinese chemical name: 2,5-dimethyl-4-((4-(1,2,2-triphenylethenyl)phenyl)ethynyl)benzaldehyde

English chemical formula: 2,5-dimethyl-4-((4-(1,2,2-triphenylvinyl)phenyl)ethynyl)benzaldehyde

Synthesis method: similar to the synthesis method of TPE-HPh, the difference is that 4-bromo-2,5-dimethylbenzaldehyde 5 is used instead of 4-bromo-2,5-dihexyloxybenzaldehyde 6; The substances added during the reaction were 2-(4-ethynylphenyl)-1,1,2-triphenylethenyl 4 (1g, 2.81mmol), 4-bromo-2,5-dimethylbenzaldehyde 5 (0.57g, 2.68mmol), bis(triphenylphosphine)palladium(II) dichloride (0.089g, 0.126mmol), cuprous iodide (0.024g, 0.121mmol) and triphenylphosphine (0.066g , 0.251mmol), to obtain the product 0.73g, yield 70%. MS: 488.2; ¹ H NMR (400MHz, CDCl ₃ ): 10.22(s,1H),7.64(s,1H),7.34(s,1H),7.29(s,1H),7.27(s,1H),7.15 -7.09(m,9H),7.08-7.01(m,8H),2.61(s,3H),2.50(s,3H).

(2) Synthesis of TPE-MPh-Bar

Chinese chemical name: 5-(2,5-dimethyl-4-((4-(1,2,2-triphenylethenyl)phenyl)ethynyl)benzylidene)pyrimidine-2,4 ,6(1H,3H,5H)-trione

English chemical formula: 5-(2,5-dimethyl-4-((4-(1,2,2-triphenylvinyl)phenyl)ethynyl)benzylidene)pyrimidine-2,4,6(1H,3H,5H)-trione

Synthesis method: Similar to the synthesis method of TPE-HPh-Bar, the difference is that TPE-MPh (370mg, 0.758mmol) and barbituric acid 3 (106mg, 0.828mmol) were used to obtain 0.30g of the product, with a yield of 65% . HRMS (MALDI-TOF): theoretical value C ₄₁ H ₃₀ N ₂ O ₃ 598.2256; measured value 598.2261; ¹ H NMR (400MHz, d ⁶ -DMSO) δ 11.55 (s, 1H), 11.32 (s, 1H), 8.45(s,1H),7.62(s,1H),7.49(s,1H),7.44(d, ² J＝8.4Hz,2H),7.30-7.22(m,9H),7.13-7.08(m,9H ),2.47(s,3H),2.35(s,3H); ¹³ C NMR (100MHz,d ⁶ -DMSO)δ162.90,161.06,152.63,150.28,143.95,142.93,142.91,142.73,141.47,139.84,135.67,135.2 ,133.64,132.38,131.12,130.90,130.80,130.72,130.69,130.62,128.01,127.96,127.85,126.86,126.78,123.93,120.80,120.27,98.73,198.77,120.80,120.27,98.73,198.77,120.80,

Example 5: The TPE-Bar, TPE-s-Bar, TPE-HPh-Bar and TPE-MPh-Bar prepared in Examples 1-4 include self-assembled micro-nano materials, organic optical waveguides, biological imaging and other applications Research

The key intermediates and final products in Figure 1 were purified and characterized by NMR spectroscopy and mass spectrometry to confirm their molecular structures. The luminescent material is soluble in common organic solvents, including THF, dichloromethane, chloroform and DMSO, and insoluble in water.

TPE-s-Bar is slowly volatilized in a mixed solvent of ethanol and chloroform to obtain TPE-s-Bar crystals, which are analyzed by X-ray diffraction. The structural diagram (ORTEP) of TPE-s-Bar is shown in Figure 2, and the crystal data are shown in Table 1.

Table 2: Summary of crystallographic data for TPE-s-Bar

As shown in Figures 3A, 3B, and 3C, the three luminescent materials TPE-s-Bar, TPE-Bar, and TPE-MPh-Bar showed obvious aggregation-induced emission (AIE) properties in the PL spectra. These compounds all emit light above 550nm, which is orange-red light. After exceeding a certain water content value (80vol% for TPE-s-Bar and TPE-Bar, 70% for TPE-MPh-Bar), with THF/ As the water content in the mixed solvent of water continues to increase, the luminous intensity rises sharply. While for TPE-HPh-Bar, due to the large electron donating ability of the hexyloxy-substituted benzene ring, an obvious twisted intramolecular charge transfer (TICT) process can be observed before AIE. As shown in Figures 4A and 4B, the photoluminescence (PL emission) of TPE-HPh-Bar in the aggregated state is red-shifted to about 630nm, compared with TPE-CHO at about 490nm emitting light, due to the introduction of the electron-withdrawing group PL emission Tauric acid has a red-shifted luminescence, and the preparation of this red light does not require complicated synthetic workload. According to the integrating sphere technique, the solid-state quantum yields of TPE-Bar, TPE-s-Bar, TPE-MPh-Bar and TPE-HPh-Bar luminescent materials are 19.1%, 20%, 9% and 37.4%, respectively.

After slowly grinding TPE-s-Bar and TPE-Bar using a mortar, a redder powder was formed, as shown in Figure 5A and 5B, and TPE-s-Bar showed red luminescence (PL) at 567 nm, as shown in Figure 6A and 6B TPE-Bar showed red luminescence (PL) at 605nm. After being fumigated with acetone vapor for 20 minutes, the initial yellow luminescence was returned, and the reversible conversion between yellow luminescence and red luminescence is easy. In addition to fumigation, heating the ground powder of TPE-s-Bar above 110°C and the ground powder of TPE-Bar at 140°C will also turn the red powder into a crystalline state and emit yellow light, showing mechanochromism behavior. Similarly, TPE-MPh-Bar also exhibited mechanochromism properties, after milling, the maximum change in luminescence was from 575 nm to 600 nm as shown in Figures 7A and 7B.

In order to study the phenomenon of mechanochromism, the activated luminescent compounds in different aggregation states were analyzed by powder X-ray diffraction (XRD). As shown in Figures 8A and 9A, the XRD diffraction pattern of the pristine sample shows many sharp diffraction peaks, indicating its crystalline structural nature, in contrast, the milled sample only shows a large diffuse halo and is thus amorphous . When the red powder was heat-treated or fumigated with acetone vapor, the sharp diffraction peaks reappeared, indicating that the amorphous powder was returned to its crystalline state by solvent fumigation or heat treatment. From the DSC data of 8B and 9B, it can be seen that a crystalline peak appears on the DSC spectrum of the ground sample, which is formed during the transition from the amorphous state to the crystalline state. The above experimental results indicate that the transition of luminescence is related to the morphological transition from crystalline to amorphous and vice versa.

Investigating the self-assembly of TPE-HPh-Bar. Drop a few drops of acetonitrile solution of TPE-HPh-Bar on the silicon substrate and volatilize naturally to form TPE-HPh-Bar nanospheres. As shown in Figures 10A, 10B, 10C and 10D, the size of the nanospheres is uniform, and the size is related to the concentration of the solution. The higher the concentration of the solution, the larger the size of the formed nanospheres. The addition of ethanol or water has basically no effect on the self-assembled morphology, but the size of the nanospheres will become smaller under the same experimental conditions. In order to obtain a uniform particle size of 500 nm, acetonitrile/ethanol (1:1 v/v) mixed solvent was used, and the concentration of TPE-HPh-Bar was 50 μM, which was 5 times the concentration of TPE-HPh-Bar in the above acetonitrile solution. For TPE-HPh-Bar, ethanol and water are poor dissolving solvents. Adding these solvents to the acetonitrile solution will accelerate the aggregation of molecules, and then form nanospheres with small particle sizes.

Considering the hydrogen bonding between barbituric acid and melamine, the effect of the addition of melamine on the nanostructure formed by TPE-HPh-Bar was studied, and the self-assembly of TPE-HPh-Bar added with melamine was studied. Since acetonitrile is a poor solvent for melamine, only part of TPE-HPh-Bar molecules interact with melamine molecules, and melamine has better solubility in DMSO solvent, so DMSO solvent was used for morphology study. First, prepare the DMSO solution of TPE-HPh-Bar, add an appropriate amount of melamine solution dissolved in DMSO, put the mixed solution at room temperature for a period of time, then add ethanol, after adding ethanol, the solution is dropped on the silicon substrate, in the open Volatile solvent under the condition, because TPE-HPh-Bar molecules are much larger than melamine molecules, so the amount of melamine is relatively high, and then make the TPE-HPh-Bar molecules and melamine molecules form a complete interaction. As shown in FIGS. 11A and 11B , nanotubes with a length of about 30 nm and a diameter of about 50 nm were formed in a mixed solvent of DMSO/ethanol (1:1 v/v) in the presence of 10 equivalents of melamine. The tube ends of most nanotubes are open, which may be related to the corrosion effect of DMSO, which is rarely observed in the composite of barbituric acid and melamine. As shown in Figures 11C and 11D, increasing melamine to 25 equivalents, the thickness of the nanorods hardly changes, but the ends of the tubes are closed. When the volume ratio of DMSO to ethanol was changed from 1:1 to 1:4, the microstructures and nanostructures became smaller and irregular. TPE-HPh-Bar molecules aggregated in mixed solvents containing a large amount of ethanol, which hindered their co-assembly with melamine molecules. On the other hand, reducing the content of DMSO reduces the corrosion effect, and the possibility of opening-shaped nanotubes is reduced.

TPE-s-Bar and TPE-HPh-Bar micro-nanorod structures with no defects on the surface show excellent optical waveguide effect. To further investigate the optical waveguide behavior of TPE-s-Bar and TPE-HPh-Bar microrods, the distance-dependent photoluminescence (PL) properties of TPE-s-Bar and TPE-HPh-Bar microrods were tested, respectively. As shown in Figures 12A and 13A, the excitation light with a wavelength of 400nm generated by an 800nm laser excites different positions of the microrods on the glass plate, and detects the luminescence at the end of the microrods, when the excited position gradually moves to the opposite end , the luminous intensity becomes weaker, which indicates that the microrods of TPE-s-Bar and TPE-HPh-Bar absorb the excitation light at the excited position, and then propagate the absorbed light to the ends of the microrods. The phenomenon of coupling light at the ends is a characteristic of the behavior of optical waveguides.

The microrods of TPE-s-Bar and TPE-HPh-Bar are used as organic optical waveguide materials, as shown in Figure 12B, 12C and 13B and 13C, and the optical loss coefficients of TPE-s-Bar and TPE-HPh-Bar microrods are detected , record the luminous intensity at the fixed end of the microrod (I _end ) and the luminous intensity at the excited position (I _body ). The light loss coefficient (α) was calculated by single exponential fitting (I _end /I _body = Aexp ^-αx , where x represents the distance between the excitation position and the light-emitting end, A represents the ratio of the light escaping from the excitation point to the light propagating along the fiber light ratio), according to which the measured α value of TPE-s-Bar is about 0.100dB/μm and that of TPE-HPh-Bar is about 0.130dB/μm, indicating that the two activated luminescent compounds have excellent light waveguide effect. The large Stokes shift helps TPE-s-Bar and TPE-HPh-Bar to overcome the reabsorption of light escaping from the excitation point, which is the main factor of light loss during propagation.

Similarly TPE-Bar and TPE-MPh-Bar microrods are also expected to be used as optical waveguide materials.

In biological applications, TPE-HPh-Bar is coated with bovine serum albumin with the assistance of the cross-linking agent glutaraldehyde, as shown in Figure 14, detected and observed by scanning electron microscopy (SEM), showing that after modification The TPE-HPh-Bar can form uniform nanoparticles, which has a good dispersion effect in the aqueous phase. The particle size of the nanoparticles is about 250nm, which is easy to be internalized by cells. Therefore, this series of luminescent materials is also expected to be applied in intracellular imaging technology.

In addition, considering the good solid-state light-emitting properties of this type of material, it can be used as a light-emitting layer and is expected to be used in organic light-emitting diode devices.

It should be understood that those skilled in the art may make improvements or changes based on the above description, and all such improvements or changes shall fall within the protection scope of the appended claims of the present invention.

Claims (10)

1. A luminescent material with aggregation-induced luminescent properties, comprising a group selected from any of the following structural formulas: Wherein, R ¹ , R ² and R ³ are respectively selected from -H, linear or branched alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, alkoxy, aryloxy, carboxy , isothiocyanate group, azido group, alkyl azido group, alkylamino group, chloroalkyl group, bromoalkyl group, iodoalkyl group, ester group, R ¹ , R ² and R ³ can also Respectively selected from the following structural formulas: or Wherein Y is O, S or Se; R ₁ and R ₂ are -H, linear or branched alkyl respectively, R ₃ and R ₄ are linear or branched alkyl or alkoxy respectively; In structural formulas I and II, at least one R ¹ , R ² or R ³ is contained respectively; Y is O, S or Se; R ₁ and R ₂ are linear or branched alkyl groups respectively; R ₃ and R ₄ are respectively is a linear or branched alkyl or alkoxy group; The tetraphenylethylene units in formulas I and II include at least one and are linked by a C-C single bond, a C=C double bond or a C≡C triple bond. 2. The luminescent material with aggregation-induced luminescent properties according to claim 1, wherein R ¹ , R ² and R ³ are all -H; Y is O. 3. The luminescent material with aggregation _- induced luminescent properties according to claim ₂ , characterized in that, in structural _{formula I} , R and R are respectively selected from -H or alkyl and R and R are the same group group; in structural formula II, R ₁ and R ₂ are both -H, R ₃ and R ₄ are respectively selected from alkyl or alkoxy and R ₃ and R ₄ are the same group. 4. The luminescent material with aggregation-induced luminescent properties according to claim 3, characterized in that, in structural formula I, R ₁ and R ₂ are both-H or both are-CH ₃ groups; in structural formula II, Both R ₃ and R ₄ are -CH ₃ or -OC ₆ H ₁₃ groups. 5. An application of the luminescent material with aggregation-induced luminescent properties according to any one of claims 1-4 in the preparation of optical waveguide materials. 6. An application of the luminescent material with aggregation-induced luminescent properties according to any one of claims 1-4 in the preparation of an organic light-emitting diode device. 7. An application of the luminescent material with aggregation-induced luminescent properties according to any one of claims 1-4 in the preparation of fluorescent dyes for intracellular imaging. 8. A method for preparing a luminescent material with aggregation-induced luminescent properties described in any one of claims 1-4, comprising the steps of: using tetraphenylethylene derivatives and barbituric acid compounds as reaction starters in Heat and reflux reaction in an organic alcohol solvent to form a precipitate, filter the precipitate, wash the filtered product with an organic solvent, and dry it in vacuum to obtain a luminescent material; Wherein the structural formula of the tetraphenylethylene derivative in the reaction starter is: or Wherein, R ¹ , R ² and R ³ are respectively selected from -H, linear or branched alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, alkoxy, aryloxy, carboxy , isothiocyanate group, azido group, alkyl azido group, alkylamino group, chloroalkyl group, bromoalkyl group, iodoalkyl group, ester group, R ¹ , R ² and R ³ can also Respectively selected from the following structural formulas: or Wherein Y is O, S or Se; R ₁ and R ₂ are -H, linear or branched alkyl respectively, R ₃ and R ₄ are linear or branched alkyl or alkoxy respectively; In the structural formula of tetraphenylethylene derivatives in the reaction starting material, there are at least one R ¹ , R ² or R ³ respectively; the tetraphenylethylene unit includes at least one, and through CC single bond, C=C double bond Or a C≡C triple bond linkage. 9. the preparation method according to claim 8, is characterized in that, the barbituric acid compound in the described reaction starter is barbituric acid or N, N-dimethyl barbituric acid; The organic alcohol solvent is methanol or ethanol; the organic solvent is selected from at least one of methanol, ethanol and ether; the precipitate can be filtered while it is hot or cooled to room temperature to obtain a solid. 10. preparation method according to claim 8 is characterized in that, also comprises the step of adding the concentrated sulfuric acid as catalyst in the process of heating reflux reaction; And after the product after filtering is washed, use ether and hexane to filter the product recrystallization steps.