A protonated product of a pyridine derivative and a complex thereof, a preparation method and application thereof

Abstract

The application provides a protonated product of a pyridine derivative and a complex thereof, a preparation method and application, and belongs to the technical field of photoelectric materials. The application realizes phosphorescence enhancement by protonating pyridine and its derivatives, and then further dopes the protonated product of pyridine and its derivatives with a polymer to prepare a phosphorescent complex film. The hydrogen bond formed by the polymer and the protonated product of pyridine and its derivatives limits the non-radiative relaxation of the compound through the rigid structure formed by the hydrogen bond, thereby improving the room-temperature phosphorescent performance. The preparation method is simple, raw materials are easy to obtain and low in cost, and the method is green and environmentally friendly. The prepared phosphorescent complex has excellent phosphorescent performance, and has foldable and tailorable characteristics, and can be applied to flexible display, colorful phosphorescent object construction, information encryption, anti-counterfeiting and the like.

Description

Technical Field

[0001] This invention relates to the field of optoelectronic materials technology, and in particular to a protonated product of a pyridine derivative and its complex, preparation method and application. Background Technology

[0002] Organic room-temperature phosphorescence (RTP) has wide applications in many fields such as bioimaging, information encryption, organic light-emitting diodes, and sensing. Lifetime and efficiency are two key factors for organic RTP materials. Long lifetime is an indispensable basic characteristic of RTP materials, while high phosphorescence efficiency is an important prerequisite for ensuring bright luminescence and promising application prospects.

[0003] To date, reported methods for achieving long lifetimes and high efficiency in organic RTPs include introducing carbonyl groups or heavy atoms, crystal engineering, forming charge-transfer states, polymerization, matrix solidification, host-guest complexation, or self-assembly. However, current strategies focus on promoting intersystem crossover (ISC) from excited states to triplet states and suppressing nonradiative decay from excited states to ground states. However, ISC is only one of three competing inactivation processes of singlet excitons; nonradiative decay via internal conversion (IC) and radiative decay via fluorescence emission to the ground state are equally important.

[0004] Suppressing IC (intense ionization) is also an effective way to improve the quantum yield of ISC (Φisc) and promote phosphorescence. However, the interactions between spins, electronic dynamics, and nuclear dynamics make the excited-state deactivation pathways intricate, resulting in a lack of directionality in IC suppression. Furthermore, phosphorescent building blocks, such as terebenzoic acid and carbazole, are key components in improving the efficiency of phosphorescent materials. However, the complexity of molecular excited states makes the design of universal phosphorescent building blocks difficult to implement in practice. Therefore, synthesizing a simple and universal strategy to enhance phosphorescence and obtaining a class of phosphorescent building blocks is of great significance and will undoubtedly have enormous scientific and market value. Summary of the Invention

[0005] The purpose of this invention is to provide a protonated product of a pyridine derivative and its complex, a preparation method and application. To address the challenge of high synthesis difficulty of existing phosphorescent compounds, a composite phosphorescent material with high synthesis yield, low cost, low pollution and high performance has been developed, and phosphorescence enhancement has been achieved.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] In a first aspect, the present invention provides a protonated product of a pyridine derivative, obtained by protonating pyridine and its derivatives, including one of: R / S-MeBINOL-PSSA, R / S-ClPPH, PPH, ClPPH, BrPPH, OMPPH, SPH, OPH, p-OMPH, ARH, QH, IQH, BrQH, and PhenH;

[0008] The structures of the protonated products of the pyridine and its derivatives are shown in formula (II):

[0009]

[0010] Secondly, the present invention also provides a method for preparing a protonated product of a pyridine derivative, wherein when the pyridine derivative is 4-phenylpyridine (PP), 4-(4-chlorophenyl)pyridine (ClPP), 4-(4-bromophenyl)pyridine (BrPP), 4-(4-methoxyphenyl)pyridine (OMPP), 4-(2-thienyl)pyridine (SP), 4-(2-furanyl)pyridine (OP), 4-methoxypyridine (p-OMP), acridine (AR), quinoline (Q), isoquinoline (IQ), 6-bromoisoquinoline (BrQ), or 1,10-phenanthroline (Phen), the method includes the following steps:

[0011] Under ice bath conditions, hydrochloric acid was added to ethanol solutions of various pyridine derivatives. After the solution became clear, the solvent was removed by rotary evaporation. The resulting solid was dissolved in a small amount of ethanol, and ether was gradually added dropwise. After a white solid precipitated, the protonated product of the pyridine derivative was obtained by filtration.

[0012] When the pyridine derivative is R / S-MeBINOL, the following steps are included:

[0013] R / S-MeBINOL was prepared from R / S-6,6'-dibromo-1,1'-bis-2-naphthol. Under ice bath conditions, poly(4-styrenesulfonic acid) solution was added to an ethanol solution of R / S-MeBINOL, and the solution turned yellow. The solvent was removed by rotary evaporation, and the obtained solid was dissolved in ethanol. Diethyl ether was gradually added dropwise, and a yellow solid was precipitated. After filtration, R / S-MeBINOL-PSSA was obtained.

[0014] When the pyridine derivative is R / S-ClPP, the following steps are included:

[0015] 4-(4-chlorophenyl)pyridine (ClPP) and R / S-chiral camphorsulfonic acid (R / S-CSA) were mixed and added to tetrahydrofuran. The solution became clear and was sonicated in an ultrasonic spectrometer for 1–30 minutes. Then hexane was added and sonicated for another 1–30 minutes. After standing, the mixture was filtered and collected to obtain a white solid, R / S-ClPPH.

[0016] Thirdly, the present invention also provides a phosphorescent complex prepared by protonated products of pyridine derivatives and polymers. The phosphorescent complex is prepared by doping polymers on protonated products of pyridine and its derivatives to form hydrogen bonds. The rigid structure formed by the hydrogen bonds restricts the nonradiative relaxation of the protonated products and improves the room temperature phosphorescence performance.

[0017] Preferably, the structure of the phosphorescent composite is shown in formula (I):

[0018]

[0019] Preferably, the polymer includes one of polyvinyl alcohol, polymethyl methacrylate, polystyrene, polyacrylonitrile, polyimide, and polyvinyl chloride.

[0020] Fourthly, the present invention also provides a method for preparing a phosphorescent composite by combining a protonated product of a pyridine derivative with a polymer, comprising the following steps:

[0021] (1) Preparation of protonated products of pyridine derivatives;

[0022] (2) Preparation of phosphorescent complex: The polymer is heated and dissolved in the first solvent to obtain a polymer solution. The protonated product of the pyridine derivative prepared in step (1) is dissolved in the second solvent to obtain a protonated product solution of the pyridine derivative. The polymer solution and the protonated product solution of the pyridine derivative are mixed evenly and evaporated to obtain the phosphorescent complex.

[0023] Preferably, in step (2), the concentration of the polymer solution is 40-60 mg / mL; the concentration of the protonated product solution of the pyridine derivative is 0.4-0.6 mg / mL; and the volume ratio of the polymer solution to the protonated product solution of the pyridine derivative is 1:100.

[0024] Preferably, in step (2), the first solvent is DMF or water, and the second solvent is DMF or ethanol.

[0025] Fifthly, the present invention also provides an application of a phosphorescent composite prepared by protonation of a pyridine derivative and a polymer in anti-counterfeiting encryption, flexible display, or construction of colorful phosphorescent objects.

[0026] The beneficial effects of this invention compared to the prior art are as follows:

[0027] (1) The present invention achieves phosphorescence enhancement by protonating pyridine and its derivatives, and then further doping the protonated products of pyridine and its derivatives with polymers to prepare a type of phosphorescent composite film. The polymer and the protonated products of pyridine and its derivatives form hydrogen bonds, and the rigid structure formed by the hydrogen bond effect restricts the nonradiative relaxation of the compound to improve the room temperature phosphorescence performance.

[0028] (2) The preparation method of the present invention is simple, the raw materials are readily available and the cost is low, and it is green and environmentally friendly. The prepared phosphorescent composite has excellent phosphorescent properties and has foldable and cuttable characteristics, which can be applied to flexible display, colorful phosphorescent object construction, information encryption, anti-counterfeiting and other fields. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 The preparation process of R-MeBINOL-PSSA, the protonated product of the pyridine derivative in Example 1;

[0031] Figure 2 The preparation process of R-ClPPH, the protonated product of the pyridine derivative in Example 2;

[0032] Figure 3 This is the preparation process for synthesizing the phosphorescent complex R-MeBINOL-PSSA@PMMA based on the protonated product R-MeBINOL-PSSA of the pyridine derivative in Example 5;

[0033] Figure 4 The preparation process for synthesizing the phosphorescent complex R-MeBINOL-PSSA@PVA based on the protonated product R-MeBINOL-PSSA of the pyridine derivative in Example 6 is as follows:

[0034] Figure 5 This is the preparation process for synthesizing the phosphorescent complex R-ClPPH@PVA based on the protonated product R-ClPPH of the pyridine derivative in Example 7;

[0035] Figure 6 Example 7 illustrates the preparation process for synthesizing phosphorescent complex PPH@PVA based on the protonated product PPH of pyridine derivatives;

[0036] Figure 7Example 7 illustrates the preparation process for synthesizing the phosphorescent complex ClPPH@PVA based on the protonated product ClPPH of a pyridine derivative;

[0037] Figure 8 Example 7 illustrates the preparation process for synthesizing the phosphorescent complex BrPPH@PVA based on the protonated product BrPPH of a pyridine derivative;

[0038] Figure 9 Example 7 illustrates the preparation process for synthesizing the phosphorescent complex OMPPH@PVA based on the protonated product OMPPH of a pyridine derivative;

[0039] Figure 10 Example 7 illustrates the preparation process for synthesizing the phosphorescent complex SPH@PVA from the protonated product SPH of a pyridine derivative;

[0040] Figure 11 Example 7 illustrates the preparation process for synthesizing phosphorescent complex OPH@PVA based on the protonated product OPH of pyridine derivatives.

[0041] Figure 12 Example 7 illustrates the preparation process for synthesizing the phosphorescent complex p-OMPH@PVA based on the protonated product p-OMPH of a pyridine derivative;

[0042] Figure 13 Example 7 illustrates the preparation process for synthesizing the phosphorescent complex ARH@PVA based on the protonated product ARH of pyridine derivatives.

[0043] Figure 14 Example 7 illustrates the preparation process for synthesizing the phosphorescent complex IQH@PVA based on the protonated product IQH of a pyridine derivative;

[0044] Figure 15 Example 7 illustrates the preparation process for synthesizing the phosphorescent complex QH@PVA based on the protonated product QH of a pyridine derivative;

[0045] Figure 16 Example 7 illustrates the preparation process for synthesizing the phosphorescent complex BrQH@PVA based on the protonated product BrQH of a pyridine derivative;

[0046] Figure 17 Example 7 illustrates the preparation process for synthesizing the phosphorescent complex PhenH@PVA based on the protonated product PhenH of a pyridine derivative;

[0047] Figure 18 The NMR spectrum of R-ClPPH, the protonated product of the pyridine derivative in Example 7 of Experimental Example 1;

[0048] Figure 19The circularly polarized emission spectra of the six composite phosphorescent thin film materials R / S-MeBINOL-PSSA@PMMA, R / S-MeBINOL-PSSA@PVA, and R / S-ClPPH@PVA prepared in Examples 5, 6, and 7 of Experimental Example 1 are shown.

[0049] Figure 20 The image shows the luminescence of the composite phosphorescent thin film material R-ClPPH@PVA prepared based on R-ClPPH in Experiment Example 1 after being folded into a bow.

[0050] Figure 21 The images show the luminescence of the composite phosphorescent thin film materials R-MeBINOL-PSSA@PMMA and R-MeBINOL-PSSA@PVA prepared based on R-MeBINOL-PSSA in Examples 5 and 6 of Experiment 1 after engraving and cutting.

[0051] Figure 22 The relevant photophysical data are for the composite phosphorescent materials prepared in Examples 5-7;

[0052] Figure 23 The preparation process of 4-(2-thienyl)pyridine (SP) and 4-(2-furanyl)pyridine (OP) in Example 8 is shown below. Detailed Implementation

[0053] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0054] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0055] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0056] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0057] This invention provides methods for preparing protonated products of pyridine derivatives, mainly including the following:

[0058] When the raw materials are 4-phenylpyridine (PP), 4-(4-chlorophenyl)pyridine (ClPP), 4-(4-bromophenyl)pyridine (BrPP), 4-(4-methoxyphenyl)pyridine (OMPP), 4-(2-thienyl)pyridine (SP), 4-(2-furanyl)pyridine (OP), 4-methoxypyridine (p-OMP), acridine (AR), quinoline (Q), isoquinoline (IQ), 6-bromoisoquinoline (BrQ), and 1,10-phenanthroline (Phen), the preparation method is as follows:

[0059] (1) Under ice bath conditions, the pyridine derivative was dissolved in ethanol, and hydrochloric acid was added to the solution until it gradually became clear;

[0060] (2) The solvent was removed by rotary evaporation to obtain a solid;

[0061] (3) Dissolve the obtained solid in ethanol and gradually add diethyl ether. A white solid precipitates out and is filtered to obtain the protonated product of the pyridine derivative.

[0062] When the raw material is R / S-MeBINOL, the preparation method is as follows:

[0063] (1) R / S-MeBINOL was prepared using R / S-6,6'-dibromo-1,1'-bis-2-naphthol as a raw material;

[0064] (2) Under ice bath conditions, when poly(4-styrene sulfonic acid) solution is added to the ethanol solution of R / S-MeBINOL, the solution turns yellow.

[0065] The solvent was removed by rotary evaporation, and the resulting solid was dissolved in ethanol.

[0066] (3) Gradually add diethyl ether, and after the yellow solid precipitates, filter to obtain the protonated product R / S-MeBINOL-PSSA.

[0067] When the raw material is R / S-ClPP, the preparation method is as follows:

[0068] (1) When 4-(4-chlorophenyl)pyridine (ClPP) and R / S-chiral camphorsulfonic acid (R / S-CSA) were mixed and added to tetrahydrofuran (THF), the solution became clear.

[0069] (2) After sonicating for 1 to 30 minutes until a white solid precipitates, add n-hexane and continue sonicating for 1 to 30 minutes. More white solid precipitates will be observed. Continue sonicating to obtain a nanostructure suspension.

[0070] (3) After standing for half an hour, a large amount of solid precipitate was observed. The white solid obtained by filtration was the protonated product R / S-ClPPH.

[0071] The protonated products of the pyridine derivatives include R / S-MeBINOL-PSSA, R / S-ClPPH, PPH, ClPPH, BrPPH, OMPPH, SPH, OPH, p-OMPH, ARH, QH, IQH, BrQH, PhenH, etc., with corresponding structures as shown in formula (II):

[0072]

[0073] Furthermore, the present invention provides a method for preparing a phosphorescent composite, which mainly includes the following steps:

[0074] (1) Preparation of protonated products of pyridine derivatives;

[0075] (2) Preparation of phosphorescent complex: The polymer is heated and dissolved in the first solvent to obtain a polymer solution. The protonated product of the pyridine derivative prepared in step (1) is dissolved in the second solvent to obtain a protonated product solution of the pyridine derivative. The polymer solution and the protonated product solution of the pyridine derivative are mixed evenly and evaporated to obtain the phosphorescent complex.

[0076] Example 1

[0077] Example 1 of this invention synthesized the protonated product R-MeBINOL-PSSA of a pyridine derivative, and the specific steps are as follows:

[0078] (1) Preparation of R-MeBINOL-PSSA, a protonated product of a pyridine derivative:

[0079] according to Figure 1 R-MeBINOL-PSSA was prepared using the method shown:

[0080] A. In a 50 mL round-bottom flask, R-6,6'-dibromo-1,1'-bis-2-naphthol (1.0 g, 2.3 mmol) and potassium iodide (1.1 g, 6.8 mmol) were added sequentially. 60 mL of acetonitrile was added to the reaction system, and the system was heated to 75 °C and stirred for 10 hours. After the reaction was complete, the system was cooled to room temperature, filtered, and a white solid was obtained. The white solid was washed with water (20 mL * 3) to obtain another white solid, which was then washed with acetone (20 mL * 3) to finally obtain the target product, a white solid R-MeBINBr (1.0 g, 97% yield).

[0081] B. In a 50 mL round-bottom flask, R-MeBINBr (1.0 g, 2.2 mmol), pyridine-4-borate (1.0 g, 6.5 mmol), tetrakis(triphenylphosphine)palladium (0.12 g, 0.1 mmol), and sodium carbonate (0.7 g, 6.6 mmol) were added sequentially. Under nitrogen protection, a mixed solvent of 50 mL of 1,4-dioxane and 50 mL of water (5:1 ratio) was added to the reaction system. The reaction system was heated to 85 °C and stirred for 24 hours. After the reaction was completed, the reaction system was cooled to room temperature, and the solvent was removed by rotary evaporation. The mixture was extracted with dichloromethane and water. The organic phase was dried over anhydrous sodium sulfate, and the solvent was removed again by rotary evaporation. Finally, the product was purified by column chromatography (eluent composition: petroleum ether / ethyl acetate = 10 / 1, v / v). The white solid obtained was the target product R-MeBINOL (0.81 g, yield 79%).

[0082] Synthesis of C,R-MeBINOL-PSSA

[0083] In a 50 mL round-bottom flask, R-MeBINOL (0.5 g, 1.1 mmol) was added. 10 mL of ethanol was added to the reaction flask, and a poly(4-styrenesulfonic acid) solution was added dropwise under ice-water bath conditions. The solution gradually turned yellow. The solvent was removed by rotary evaporation to obtain a yellow solid. The yellow solid was dissolved in ethanol, and then added dropwise to diethyl ether (eluent composition: ethanol / diethyl ether = 1:10, v / v). A yellow solid precipitated out, and the precipitate was obtained by filtration. The final product was the yellow solid R-MeBINOL-PSSA (0.56 g, 95% yield).

[0084] A transparent composite phosphorescent thin film material, S-MeBINOL-PSSA, based on the protonated product of a pyridine derivative, was prepared using S-6,6'-dibromo-1,1'-bis-2-naphthol as a raw material.

[0085] Example 2

[0086] Example 2 of this invention synthesized the protonated product R-ClPPH of a pyridine derivative, and the specific steps are as follows:

[0087] according to Figure 2 The procedure is as follows: 4-chlorophenylpyridine (0.5 g, 2.6 mmol) and R-chiral camphorsulfonic acid (R-CSA, 0.6 g, 2.6 mmol) are added to a 20 mL centrifuge tube. 10 mL of tetrahydrofuran (THF) is added, and the solution becomes clear. After sonicating for 10 minutes in an ultrasonic spectrometer, a white solid precipitates. Then, 10 mL of n-hexane is added, and more white solid precipitates. Sonication continues for another 10 minutes to obtain a nanostructure suspension. After standing for half an hour, a large amount of solid precipitates out. The white solid R-ClPPH (0.56 g, yield 93%) is collected by filtration.

[0088] A protonated product S-ClPPH of a pyridine derivative was prepared using S-CSA as a raw material.

[0089] Example 3

[0090] Example 3 of this invention synthesized the protonated product PPH of a pyridine derivative, and the specific steps are as follows:

[0091] In a 50 mL round-bottom flask, phenylpyridine (PP) (0.5 g, 3.2 mmol) was added. 10 mL of ethanol was added to the reaction flask, and hydrochloric acid solution was added dropwise under ice-water bath conditions. The solution gradually became clear. The solvent was removed by rotary evaporation, yielding a white solid. The white solid was dissolved in a small amount of ethanol, and then added dropwise to diethyl ether (eluent composition: ethanol / diethyl ether = 1:10, v / v). A white solid precipitated, and the precipitate was filtered to obtain a yellow solid. The final product was the white solid PPH (0.58 g, yield 96%).

[0092] Example 4

[0093] In Example 4 of this invention, following the preparation method of Example 3, ClPPH, BrPPH, OMPPH, SPH, OPH, p-OMPH, ARH, QH, IQH, BrQH, and PhenH were prepared using 4-(4-chlorophenyl)pyridine (ClPP), 4-(4-bromophenyl)pyridine (BrPP), 4-(4-methoxyphenyl)pyridine (OMPP), 4-(2-thienyl)pyridine (SP), 4-(2-furanyl)pyridine (OP), 4-methoxypyridine (p-OMP), acridine (AR), quinoline (Q), isoquinoline (IQ), 6-bromoisoquinoline (BrQ), and 1,10-phenanthroline (Phen) as raw materials.

[0094] Example 5

[0095] Example 5 of this invention synthesizes the phosphorescent complex R-MeBINOL-PSSA@PMMA based on the protonated product R-MeBINOL-PSSA of the pyridine derivative prepared in Example 1. The specific steps are as follows:

[0096] Polymethyl methacrylate (PMMA) was heated in DMF solution until completely dissolved to prepare a 40 mg / mL solution. 0.4 mg of R-MeBINOL-PSSA was dissolved in 10 μL of DMF solvent to prepare a 40 mg / mL solution, which was then added dropwise to 1 mL of PMMA in DMF solution. After thorough mixing, the mixture was dropped onto a quartz or glass slide, and the solvent was evaporated to obtain the transparent composite phosphorescent thin film material R-MeBINOL-PSSA@PMMA. The preparation route and luminescence effect of the composite phosphorescent thin film material are as follows. Figure 3 As shown.

[0097] Example 6

[0098] Example 6 of this invention synthesizes the phosphorescent complex R-MeBINOL-PSSA@PVA based on the protonated product R-MeBINOL-PSSA of the pyridine derivative prepared in Example 1. The specific steps are as follows:

[0099] Polyvinyl alcohol (PVA) was heated in an aqueous solution until completely dissolved to prepare a 40 mg / mL PVA solution. 0.4 mg of R-MeBINOL-PSSA prepared in Example 1 was dissolved in 10 μL of ethanol to prepare a 40 mg / mL solution. This solution was then added dropwise to 1 mL of PVA aqueous solution and thoroughly mixed. The mixture was then dropped onto a quartz or glass plate, and the solvent was evaporated to obtain the transparent composite phosphorescent thin film material R-MeBINOL-PSSA@PVA. The preparation route and luminescence effect of the composite phosphorescent thin film material are as follows. Figure 4 As shown.

[0100] Example 7

[0101] Example 7 of this invention adopts the method of Example 6, and synthesizes phosphorescent composites S / R-ClPPH@PVA, PPH@PVA, ClPPH, BrPPH, OMPPH, SPH, OPH, p-OMPH, ARH, QH, IQH, BrQH, and PhenH using protonated products of pyridine derivatives S / R-ClPPH, PPH@PVA, ClPPH@PVA, BrPPH@PVA, OMPPH@PVA, SPH@PVA, OPH@PVA, p-OMPH@PVA, ARH@PVA, QH@PVA, IQH@PVA, BrQH@PVA, and PhenH@PVA, respectively. The preparation routes and luminescence effects of each composite phosphorescent thin film material are as follows. Figure 5-17 As shown.

[0102] Example 8

[0103] This invention synthesizes 4-(2-thienyl)pyridine (SP) and 4-(2-furanyl)pyridine (OP), and the specific steps are as follows:

[0104] according to Figure 23 SP and OP were prepared using the method shown:

[0105] In a 250 mL round-bottom flask, 4-bromopyridine hydrochloride (1.0 g, 5.1 mmol), 2-thiopheneboronic acid (1 g, 7.6 mmol), tetrakis(triphenylphosphine)palladium (0.28 g, 0.25 mmol), and sodium carbonate (1.6 g, 15.3 mmol) were added sequentially. Under nitrogen protection, a mixture of 60 mL of DMF and water (3:1 ratio) was added to the reaction system, and the mixture was heated to 90 °C and stirred for 12 hours. After the reaction was complete, the reaction system was cooled to room temperature, and the solvent was removed by vacuum distillation. The mixture was extracted with dichloromethane and water. The extracted organic phase was dried over anhydrous sodium sulfate, and the solvent was removed again by vacuum distillation. Finally, the product SP (0.71 g, 87% yield) was purified by column chromatography (eluent composition: petroleum ether / ethyl acetate = 20 / 1).

[0106] In a 250 mL round-bottom flask, 4-bromopyridine hydrochloride (1.0 g, 5.1 mmol), 2-furanboronic acid (0.85 g, 7.6 mmol), tetrakis(triphenylphosphine)palladium (0.28 g, 0.25 mmol), and sodium carbonate (1.6 g, 15.3 mmol) were added sequentially. Under nitrogen protection, a mixture of 60 mL of DMF and water (3:1 ratio) was added to the reaction system, and the mixture was heated to 90 °C and stirred for 12 hours. After the reaction was complete, the reaction system was cooled to room temperature, and the solvent was removed by vacuum distillation. The mixture was extracted with dichloromethane and water. The extracted organic phase was dried over anhydrous sodium sulfate, and the solvent was removed again by vacuum distillation. Finally, the mixture was purified by column chromatography (eluent composition: petroleum ether / ethyl acetate = 20 / 1, v / v), and the white solid obtained was the target product OP (0.65 g, yield 89%).

[0107] Experimental Example 1

[0108] Experimental Example 1 of this invention characterized the composite phosphorescent thin film materials prepared in Examples 1-3. The specific steps are as follows:

[0109] (1) Take the composite phosphorescent thin film material prepared based on R-ClPPH in Example 3 and detect its NMR spectrum (see Figure 18 The circularly polarized emission spectra of the six composite phosphorescent thin film materials prepared in Examples 1-3 were also detected (see...). Figure 19 ).

[0110] Depend on Figure 18 It can be seen that the compound R / S-ClPPH obtained by the method for preparing pyridine derivative protonated products provided by this invention has high purity. Figure 19 It is known that the phosphorescent composites R / S-MeBINOL-PSSA@PVA, R / S-MeBINOL-PSSA@PMMA, and S / R-ClPPH@PVA prepared by doping the prepared compounds with polymers PVA and PMMA possess chiral properties, thus achieving circularly polarized organic room-temperature phosphorescence.

[0111] (2) The composite phosphorescent thin film material prepared in Example 3 was folded into a bow and its phosphorescence was tested. The results are shown in [the table below]. Figure 20 .

[0112] Depend on Figure 20 It can be seen that the composite phosphorescent thin film material prepared in Example 3 of the present invention can continuously display a butterfly under 254nm ultraviolet light irradiation and 0.3s after the ultraviolet light is turned off.

[0113] (3) In Examples 1 and 2, two different luminescent composite phosphorescent thin film materials prepared based on R-MeBINOL-PSSA were spliced ​​together to form multicolored flowers and the number "0816". Various 3D patterns were prepared using engraving, cutting, and folding techniques. Figure 21 .

[0114] Figure 21 The composite phosphorescent film material of the present invention has the characteristics of being foldable, multi-colored, and flexible, and can be used for the construction of flexible 3D phosphorescent objects and information encryption.

[0115] Experimental Example 2

[0116] Experimental Example 2 of this invention tested the relevant photophysical data of the composite phosphorescent materials prepared in Examples 1-15, and the results are shown in […]. Figure 22 .

[0117] Depend on Figure 22 It is known that the protonation of pyridine derivatives can be further restricted using these two different polymers, thereby significantly increasing phosphorescence lifetime or quantum yield.

[0118] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited to the specific details of the above embodiments. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. Furthermore, it should be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction, avoiding unnecessary repetition. In addition, various different embodiments of the present invention can also be arbitrarily combined, as long as they do not violate the spirit of the present invention, and should also be considered as part of the content disclosed in the present invention.

Claims

1. A protonated product of a pyridine derivative, obtained by protonating pyridine and its derivatives, characterized in that, include: One of R / S-MeBINOL-PSSA, R / S-ClPPH, ClPPH, BrPPH, OMPPH, OPH, p-OMPH, and BrQH; The structures of the protonated products of the pyridine and its derivatives are shown in formula (II): Formula (II); When the pyridine derivative is ClPP, BrPP, OMPP, OP, p-OMP, or BrQ, the following steps are included: Under ice bath conditions, hydrochloric acid was added to ethanol solutions of various pyridine derivatives. After the solution became clear, the solvent was removed by rotary evaporation. The resulting solid was dissolved in a small amount of ethanol, and ether was gradually added dropwise. After a white solid precipitated, the protonated product of the pyridine derivative was obtained by filtration. When the pyridine derivative is R / S-MeBINOL, the following steps are included: R / S-MeBINOL was prepared from R / S-6,6'-dibromo-1,1'-bis-2-naphthol. Under ice bath conditions, poly(4-styrenesulfonic acid) solution was added to an ethanol solution of R / S-MeBINOL, and the solution turned yellow. The solvent was removed by rotary evaporation, and the obtained solid was dissolved in ethanol. Diethyl ether was gradually added dropwise, and after the yellow solid precipitated, it was filtered to obtain R / S-MeBINOL-PSSA. When the pyridine derivative is R / S-ClPP, the following steps are included: 4-(4-chlorophenyl)pyridine was mixed with R / S-chiral camphorsulfonic acid and added to tetrahydrofuran. The solution became clear and was sonicated in an ultrasonic spectrometer for 1-30 minutes. Then hexane was added and sonicated for another 1-30 minutes. After standing, the mixture was filtered and collected to obtain a white solid, R / S-ClPPH.

2. A phosphorescent complex prepared by a protonated product of a pyridine derivative and a polymer, characterized in that, The phosphorescent composite is based on the protonated product of the pyridine derivative described in claim 1, doped with a polymer to form hydrogen bonds. The rigid structure formed by the hydrogen bonds restricts the nonradiative relaxation of the protonated product, thereby improving the room temperature phosphorescence performance.

3. The phosphorescent complex prepared by the protonated product of the pyridine derivative and the polymer according to claim 2, characterized in that, The structure of the phosphorescent composite is shown in formula (I): Equation (I).

4. The phosphorescent complex prepared by the protonated product of the pyridine derivative and the polymer according to claim 2, characterized in that, The polymer includes one of polyvinyl alcohol, polymethyl methacrylate, polyacrylonitrile, and polyimide.

5. A method for preparing a phosphorescent composite based on the protonated product of the pyridine derivative of claim 1 and a polymer, characterized in that, Includes the following steps: (1) Preparation of protonated products of pyridine derivatives; (2) Preparation of phosphorescent complex: The polymer is heated and dissolved in the first solvent to obtain a polymer solution. The protonated product of the pyridine derivative prepared in step (1) is dissolved in the second solvent to obtain a protonated product solution of the pyridine derivative. The polymer solution and the protonated product solution of the pyridine derivative are mixed evenly and evaporated to obtain the phosphorescent complex.

6. The method for preparing a phosphorescent composite with a polymer from a protonated product of a pyridine derivative according to claim 5, characterized in that, In step (2), the concentration of the polymer solution is 40-60 mg / mL; the concentration of the protonated product solution of the pyridine derivative is 0.4-0.6 mg / mL; the volume ratio of the polymer solution to the protonated product solution of the pyridine derivative is 1:100; the first solvent is DMF or water, and the second solvent is DMF or ethanol.

7. The application of a phosphorescent composite prepared by a protonated product of a pyridine derivative and a polymer according to any one of claims 2-4 or the method for preparing a phosphorescent composite prepared by a protonated product of a pyridine derivative and a polymer according to any one of claims 5-6 in anti-counterfeiting encryption, flexible display or multi-colored phosphorescent object construction.

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