A multi-color luminescent metal-organic macrocyclic dye molecule, its preparation method and application

Abstract

The present invention discloses a multi-color luminescent metal-organic macrocyclic dye molecule, its preparation method and application in controllable luminescence, belonging to the technical field of organic luminescent materials, and its structural formula is shown as Formula I in the specification. The preparation method includes: constructing by coordination-directed self-assembly of a pyridine derivative ligand containing triphenylamine and a benzothiadiazole nitrate ligand containing platinum metal. The energy transfer efficiency of this metal-organic macrocycle is different in solvents with different polarities. In the low-polarity solvent toluene, the fluorescence color is light purple. In the medium-polarity solvent ethyl acetate, the fluorescence shows white luminescence. In high-polarity solvents, the solution fluorescence color is red. Therefore, multi-color luminescence can be achieved by regulating energy transfer through solvent polarity. The metal-organic macrocyclic dye molecule with solvent-controllable multi-color luminescence of the present invention has good application prospects in the fields of white light emission and color-tunable optoelectronic materials.

Description

Technical Field

[0001] The present invention belongs to the technical field of organic light-emitting materials, and relates to a multicolor-emitting metal-organic macrocyclic dye molecule, a preparation method thereof, and an application thereof in controllable light emission. Background Art

[0002] Optical functional materials with multicolor luminescence conversion have received extensive attention from scientific research workers because they are sensitive to external environments (such as temperature, solvent, light, pH, etc.), and they have shown great potential in the fields of light harvesting, photocatalysis, photodynamic therapy, light-controlled host-guest release, light-emitting devices, etc. However, such luminescent materials usually require the introduction of multiple stimulus-responsive sites and the modification of fluorescent groups, making the synthesis very difficult. At present, it is still a great challenge to design and synthesize a single-molecule system to precisely regulate the fluorescence color through solvent polarity.

[0003] Therefore, how to develop a multicolor-emitting metal-organic macrocyclic dye molecule, a preparation method thereof, and an application thereof in controllable light emission is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0004] In view of this, the present invention provides a multicolor-emitting metal-organic macrocyclic dye molecule, a preparation method thereof, and an application thereof in controllable light emission.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A multicolor-emitting metal-organic macrocyclic dye molecule, the structural formula of which is shown in Formula I:

[0007]

[0008] The present invention also provides a preparation method of the above-mentioned multicolor-emitting metal-organic macrocyclic dye molecule, comprising the following steps: constructed by coordination-directed self-assembly of a pyridine derivative ligand containing triphenylamine and a benzothiadiazole nitrate ligand containing platinum metal;

[0009] The structural formula of the above-mentioned pyridine derivative containing triphenylamine is shown in Formula II:

[0010]

[0011] The structural formula of the above-mentioned benzothiadiazole nitrate ligand containing platinum metal is shown in Formula III:

[0012]

[0013] Further, the preparation method of the above-mentioned multicolor-emitting metal-organic macrocyclic dye molecule comprises the following steps:

[0014] (1) Add the pyridine derivative ligand containing triphenylamine and the platinum-containing benzothiadiazole nitrate ligand into a reaction vessel, dissolve them in a mixed solution of acetone and water, and heat and stir for reaction.

[0015] (2) After the reaction is completed, add a saturated aqueous solution of potassium hexafluorophosphate dropwise to the reaction solution to precipitate a yellow solid. Stop the reaction, centrifuge the reaction solution, remove the supernatant, wash with distilled water, and dry the solvent to obtain the above-mentioned multicolor luminescent metal-organic macrocyclic dye molecule.

[0016] Furthermore, in step (1), the molar ratio of the above-mentioned pyridine derivative ligand containing triphenylamine to the platinum-containing benzothiadiazole nitrate ligand is 1:1.

[0017] Furthermore, every 0.01 mmol of the above-mentioned pyridine derivative ligand containing triphenylamine and 0.01 mmol of the platinum-containing benzothiadiazole nitrate ligand are dissolved in 2.5 mL of a mixed solution of acetone and water, the volume ratio of acetone to water is 4:1, the volume ratio of acetone to the saturated aqueous solution of potassium hexafluorophosphate is 1:1, and the concentration of the saturated aqueous solution of potassium hexafluorophosphate is 14.94 mol / L.

[0018] The beneficial effects of adopting the above further technical solution: The above solvent ratio is more conducive to the assembly of the ligand, and the assembly yield is higher.

[0019] Furthermore, in step (1), the above heating temperature is 50 °C, the stirring speed is 600 r / min, and the reaction time is 10 - 12 hours.

[0020] The beneficial effects of adopting the above further technical solution: The above heating temperature can increase the molecular movement rate on the basis of preventing the solvent from boiling, and it is easier to reach the reaction equilibrium state.

[0021] Furthermore, in step (2), the above dropping rate is 0.2 mL / s.

[0022] The beneficial effects of adopting the above further technical solution: The above dropping rate can effectively perform ion exchange, generate metal-organic macrocycles, and form uniform yellow precipitates.

[0023] Furthermore, in step (2), the above centrifugation speed is 6000 r / min, and the centrifugation time is 5 min.

[0024] The beneficial effects of adopting the above further technical solution: The above centrifugation method is conducive to the effective separation of the solid phase and the liquid phase.

[0025] Even further, in step (2), the above washing with distilled water and drying the solvent are repeated 3 times.

[0026] The beneficial effect of adopting the above further technical solution is that the above washing times can remove inorganic salts as much as possible and reduce interference with subsequent spectral testing.

[0027] The present invention also provides an application of the above-mentioned multicolor luminescent metal organic macrocyclic dye molecule in controllable luminescence. In the application in controllable luminescence, the above-mentioned multicolor luminescent metal organic macrocyclic dye molecule exhibits purple fluorescence in low-polarity solvents, white fluorescence in medium-polarity solvents, and orange-red fluorescence in high-polarity solvents.

[0028] Furthermore, the multicolor luminescent metal organic macrocyclic dye molecule exhibits white light emission in ethyl acetate.

[0029] The present invention has the following beneficial effects: A metal-organic macrocyclic dye molecule based on an energy donor and an energy acceptor was designed and synthesized. A triphenylamine group serves as the energy donor, and a benzothiadiazole group serves as the energy acceptor. These two groups are modified with pyridine and platinum coordination groups, respectively, to efficiently construct a metal-organic macrocyclic dye through coordination-directed self-assembly. This metal-organic macrocyclic dye exhibits varying energy transfer efficiencies in solvents of varying polarity. In the low-polarity solvent toluene, the fluorescence emission peaks are at 425nm and 570nm, respectively, with a pale purple fluorescence color. In the medium-polarity solvent ethyl acetate, the 425nm emission peak intensity weakens, resulting in a white fluorescence emission. In high-polarity solvents, only the 570nm peak is observed, and the solution fluorescence color is red. Therefore, multicolor luminescence can be achieved by regulating energy transfer through solvent polarity. Transient absorption spectroscopy also verified the influence of solvent polarity on the energy transfer process. In summary, the present invention prepares a metal-organic macrocyclic dye molecule with solvent-controllable multicolor luminescence, which has promising application prospects in the fields of white-light emission and color-tunable optoelectronic materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The structures of the ligands and organometallic macrocycles shown, along with a synthetic scheme;

[0031] Figure 2 Shown is the pure metal organic macrocycle 1 H NMR spectrum;

[0032] Figure 3 Shown is the pure metal organic macrocycle 31 P NMR spectrum;

[0033] Figure 4 Shown are the steady-state UV absorption spectra of metal organic macrocycles in solvents of different polarities;

[0034] Figure 5 Shown are the steady-state fluorescence emission spectra of metal organic macrocycles in solvents of different polarities;

[0035] Figure 6The fluorescence emission CIE spectra of metal-organic macrocycles in different polar solvents are shown;

[0036] Figure 7 The fluorescence emission CIE spectra of metal-organic macrocycles in ethyl acetate solvent are shown;

[0037] Figure 8 The transient absorption spectra of metal-organic macrocycles in ethyl acetate solvent are shown;

[0038] Figure 9 The transient absorption spectra of the pyridine ligand of triphenylamine in ethyl acetate solvent are shown;

[0039] Figure 10 The transient absorption spectra of the platinum-containing ligand molecule of benzothiadiazole in ethyl acetate solvent are shown. Detailed implementation manners

[0040] Next, the technical solutions in the embodiments of the present invention will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0041] Example 1

[0042] The preparation method of the multicolor-emitting metal-organic macrocycle dye molecule, referring to the synthesis flow chart shown in Figure 1 , includes the following steps:

[0043] (1) Add 5.47 mg (i.e., 0.01 mmol) of the pyridine derivative ligand containing triphenylamine and 11.67 mg (i.e., 0.01 mmol) of the benzothiadiazole nitrate ligand containing platinum metal into a 4 ml reaction flask, add a small magnetic stirrer, then add 2.0 ml of acetone and 0.5 ml of secondary distilled water, heat and stir the reaction at 50 °C, the stirring speed is 600 r / min, and the reaction time is 10 hours;

[0044] (2) After the reaction is completed, add 2.0 mL of a saturated aqueous solution of potassium hexafluorophosphate with a concentration of 14.94 mol / L dropwise to the reaction solution at a dropping speed of 0.2 mL / s, yellow precipitate will precipitate, stop the reaction, centrifuge the reaction solution at a centrifugation speed of 6000 r / min for 5 min, remove the supernatant, wash with distilled water, dry the solvent by suction, repeat 3 times, and finally dry the non-dried liquid with a vacuum pump to obtain the dry target compound multicolor-emitting metal-organic macrocycle dye molecule.

[0045] The hydrogen spectrum and phosphorus spectrum of the compound are as shown in Figure 2 and Figure 3 shown.

[0046] Experiment on Controllable Luminescence of Fluorescent Dye Molecules by Fluorescence Method:

[0047] 1. Study on Ultraviolet Absorption of Metal-Organic Macrocyclic Molecules in Different Solvents.

[0048] Transfer 150 μL of the solution of the macrocyclic molecule in Example 1 (0.2 mM) into a series of 5-mL colorimetric tubes respectively, and then transfer 2850 μL of different polar solvents, namely toluene (Tol), ethyl acetate (EA), tetrahydrofuran (THF), acetone (Acetone), and dimethyl sulfoxide (DMSO) in turn. Mix the above solutions evenly. The concentration of the dye molecule in different solvents is 10 μM. Then transfer 2 mL of a series of solutions with this concentration into a cuvette, and measure the corresponding ultraviolet absorption spectrum at room temperature ( Figure 4 ). It is found that the macrocyclic molecule has absorption in the range of 300 - 550 nm in various solvents, and the main absorption peaks are located at 350 - 400 nm and 400 - 550 nm. However, the ultraviolet-visible absorption spectrum of the macrocyclic molecule does not show obvious solvent dependence. This phenomenon is attributed to the fact that solvent polarity or hydrogen bonding does not affect the energy level of the ground state. However, through the maximum absorption wavelength of the ultraviolet absorption of the macrocyclic molecule in different solvents, it can be determined that the excitation wavelength for fluorescence emission test and transient absorption test of the macrocyclic molecule in different solvents is selected as 350 nm.

[0049] 2. Research on Solvent-Tunable Multicolor Fluorescence Based on Metal-Organic Macrocycles.

[0050] Transfer 2 mL of the solution of the macrocyclic molecule in Example 1 (10 μM) in different solvents into quartz cuvettes (with a thickness of 1.0 cm) respectively, and measure their fluorescence emission spectra at room temperature ( Figure 5 ). It is found that the range of the emission spectrum is between 380 - 650 nm. In the low-polarity solvent toluene, the fluorescence emission peaks are near 425 nm and 570 nm respectively. In the medium-polarity solvents ethyl acetate and tetrahydrofuran, the intensity of the emission peak near 425 nm weakens. In high-polarity solvents, only a peak appears near 570 nm. More importantly, in ethyl acetate, the intensity of the emission peaks at 425 nm and 570 nm is roughly the same, and the fluorescence color shows white.

[0051] Experiments show that this metal-organic macrocycle can display multicolor luminescence effects from purple light to white light and then to orange-red fluorescence with the change of solvent polarity ( Figure 6 ). When in ethyl acetate, it shows white light emission, and the chromaticity coordinates are (0.31, 0.34), which is very close to the value of the theoretical white light (0.33, 0.33) ( Figure 7 ). As a supramolecular metal-organic macrocycle, it is expected to be an outstanding candidate material for white light emission and color-tunable optoelectronic materials.

[0052] 3. Study on the excited state dynamics of macrocyclic molecules in ethyl acetate.

[0053] 0.8 ml of the solution of the macrocyclic molecule (10 μM) in Example 1, 0.8 ml of the pyridine derivative ligand containing triphenylamine (10 μM), and 0.8 ml of the platinum-containing ligand molecule of benzothiadiazole (10 μM) in ethyl acetate solvent were respectively pipetted into a quartz cuvette (with a thickness of 1.0 mm), and their transient absorption spectra ( Figure 8 , Figure 9 and Figure 10 ) were respectively measured at room temperature. In the excited state absorption spectrum of the macrocyclic molecule, the excited state absorption at 400 nm - 450 nm and 450 nm - 550 nm mainly originated from the pyridine derivative ligand containing triphenylamine, and the excited state absorption peak at 600 nm - 680 nm mainly originated from the platinum-containing ligand of benzothiadiazole. The intensity of the excited state absorption of the macrocyclic molecule at 600 nm - 680 nm first increased and then decayed, indicating that the enhancement of the excited state absorption peak here originated from the energy transfer of the pyridine derivative ligand of triphenylamine to the platinum-containing ligand molecule of benzothiadiazole, fully demonstrating the energy transfer process in this system.

[0054] The description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. A multicolor luminescent metal-organic macrocyclic dye molecule, characterized in that, Its structural formula is shown in Formula I:

2. A method for preparing the multi-color luminescent metal-organic macrocyclic dye molecule according to claim 1, characterized in that, It includes the following steps: It is constructed by the coordination-directed self-assembly of a pyridine derivative ligand containing triphenylamine and a benzothiadiazole nitrate ligand containing a platinum metal; The structural formula of the pyridine derivative ligand containing triphenylamine is shown in Formula II: The structural formula of the benzothiadiazole nitrate ligand containing a platinum metal is shown in Formula III:

3. The preparation method of the multi-color luminescent metal-organic macrocyclic dye molecule according to claim 2, characterized in that, It includes the following steps: (1) Add the pyridine derivative ligand containing triphenylamine and the benzothiadiazole nitrate ligand containing a platinum metal into a reaction vessel, dissolve them in a mixed solution of acetone and water, and heat and stir for reaction; (2) After the reaction is completed, dropwise add a saturated aqueous solution of potassium hexafluorophosphate to the reaction solution to precipitate a yellow solid, stop the reaction, centrifuge the reaction solution, remove the supernatant, wash with distilled water, and dry the solvent to obtain the multicolor luminescent metal-organic macrocyclic dye molecule.

4. The preparation method of the multi-color luminescent metal-organic macrocyclic dye molecule according to claim 3, wherein, In step (1), the molar ratio of the pyridine derivative ligand containing triphenylamine to the benzothiadiazole nitrate ligand containing a platinum metal is 1:

1.

5. The preparation method of the multi-color luminescent metal-organic macrocyclic dye molecule according to claim 3, characterized in that, 0.01 mmol of the pyridine derivative ligand containing triphenylamine and 0.01 mmol of the benzothiadiazole nitrate ligand containing a platinum metal are dissolved in 2.5 mL of a mixed solution of acetone and water, the volume ratio of acetone to water is 4:1, the volume ratio of acetone to the saturated aqueous solution of potassium hexafluorophosphate is 1:1, and the concentration of the saturated aqueous solution of potassium hexafluorophosphate is 14.94 mol / L.

6. The preparation method of the multicolor luminescent metal-organic macrocyclic dye molecule according to claim 3, wherein, In step (1), the heating temperature is 50 °C, the stirring speed is 600 r / min, and the reaction time is 10 - 12 hours.

7. The preparation method of the multi-color luminescent metal-organic macrocyclic dye molecule according to claim 3, wherein, In step (2), the dropping rate is 0.2 mL / s.

8. The preparation method of the multi-color luminescent metal-organic macrocyclic dye molecule according to claim 2, wherein, In step (2), the centrifugation speed is 6000 r / min, and the centrifugation time is 5 min.

9. Use of the multicolor luminescent metal-organic macrocyclic dye molecule according to claim 1 in controllable luminescence, characterized in that, The multicolor luminescent metal-organic macrocyclic dye molecule exhibits purple fluorescence in a low-polarity solvent, white fluorescence in a medium-polarity solvent, and orange-red fluorescence in a high-polarity solvent.

10. Use of the multicolor luminescent metal-organic macrocyclic dye molecule according to claim 9 in controllable luminescence, characterized in that, The multicolor luminescent metal-organic macrocyclic dye molecule exhibits white-light fluorescence emission in ethyl acetate.

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