A fluorene ring-based organic material and its preparation method and application

Abstract

The invention discloses a kind of organic material based on fluorene ring and its preparation method and application, the present invention synthesizes a kind of organic material 9-bis(3-benzoic acid)ethylene-fluorene based on fluorene ring and carboxyl group for the first time, the material has obvious aggregation-induced luminescence effect, its luminous performance is weak in benign solvent, and the luminous performance in poor solvent is strong. The material can be used for detecting aqueous phase permanganate, and simultaneously because it is carboxyl group, compared to other fluorene compounds, can be more with the metal species of oxygen coordination, is more widely used, and preparation method is simple, yield is high, reaction activity is good, can be applied and promoted on a large scale.

Description

Technical Field

[0001] The present invention belongs to the technical field of preparation of organic compounds, and in particular relates to an organic material based on a fluorene ring, and a preparation method and application thereof. Background Art

[0002] Polycyclic aromatic hydrocarbons (PAHs) have garnered significant attention over the past few decades, particularly in materials science, due to their unique electrical and optical properties. Fluorene, the simplest methylene-bridged aromatic hydrocarbon (MBA), is an important PAH compound and a crucial component of materials science. Fluorene compounds possess a unique biphenyl structure, a large intramolecular conjugation effect, and excellent photothermal stability, offering promising applications in optoelectronic materials, biomedicine, and other fields.

[0003] In this context, the development of more structurally diverse fluorene-containing materials is of great significance. Currently, compounds synthesized based on fluorene rings all use pyridine-type ligands, which greatly limits their application range. There is an urgent need for a new organic material that can coordinate with more metals. Summary of the Invention

[0004] The purpose of this section is to summarize some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and title of this application to avoid obscuring the purpose of this section, the abstract and the title of the invention, and such simplifications or omissions should not be used to limit the scope of the present invention.

[0005] In view of the above problems and / or the problems existing in the prior art, the present invention is proposed.

[0006] Therefore, the purpose of the present invention is to overcome the deficiencies in the prior art and provide an organic material based on a fluorene ring, wherein the material is carboxyl-containing 9-bis(3-benzoic acid)ethylene-fluorene, the structural formula of which is shown in Formula A;

[0007]

[0008] As a preferred embodiment of the fluorene ring-based organic material of the present invention, the material has an aggregation-induced emission effect, has weak luminescence performance in benign solvents, and has strong luminescence performance in poor solvents.

[0009] Another object of the present invention is to overcome the deficiencies in the prior art and provide an application of an organic material based on a fluorene ring, including that the material can be used to detect aqueous permanganate with a quenching constant of 4.37×10 4 M -1 , the detection limit was 4.55×10 -3 mM.

[0010] Another object of the present invention is to overcome the deficiencies in the prior art and provide a method for preparing an organic material based on a fluorene ring.

[0011] In order to solve the above technical problems, the present invention provides the following technical solutions: comprising:

[0012] Preparation of 9-bis(methyl 3-benzoate)ethylene-fluorene:

[0013] 10-Dibromoethylene-fluorene, 3-methoxycarbonylphenylboronic acid, anhydrous potassium carbonate, and tetrakis(triphenylphosphine)palladium catalyst are added to a mixed solvent of toluene, methanol, and water, and heated to 60-140° C. under nitrogen protection for 10-30 hours. After completion of the reaction, the mixture is extracted three times with dichloromethane, the organic layer is collected, dried over anhydrous magnesium sulfate, and evaporated under reduced pressure. A crude product is obtained by column chromatography using ethyl acetate and n-hexane as eluents, and then washed with n-hexane to obtain a light yellow product, which is 9-bis(methyl 3-benzoate)ethylene-fluorene;

[0014] Preparation of 9-bis(3-benzoic acid)ethylene-fluorene:

[0015] 9-bis(3-benzoic acid methyl ester)ethylene-fluorene and sodium hydroxide are added to a mixed solvent of tetrahydrofuran, methanol and water, heated to 60-140°C under nitrogen protection, reacted for 10-30 hours, evaporated under reduced pressure, acidified with hydrochloric acid to a pH <1, the precipitate is filtered out, and washed with water to obtain a light yellow product, which is the organic material, 9-bis(3-benzoic acid)ethylene-fluorene.

[0016] As a preferred embodiment of the method for preparing the fluorene ring-based organic material of the present invention, the method comprises the following steps: preparing 9-bis(methyl 3-benzoate)ethylene-fluorene, wherein the molar ratio of 9-dibromoethylene-fluorene, 3-methoxycarbonylphenylboric acid, anhydrous potassium carbonate, and tetrakis(triphenylphosphine)palladium is 1:1-5:4-6:0.1-0.2.

[0017] As a preferred embodiment of the method for preparing the fluorene ring-based organic material of the present invention, wherein: in the preparation of 9-bis(methyl 3-benzoate)ethylene-fluorene, the mixed solvent corresponding to each 1 mmol of 9-dibromoethylene-fluorene is 100 to 300 mL.

[0018] As a preferred embodiment of the method for preparing the fluorene ring-based organic material of the present invention, the volume ratio of toluene, methanol and water in the mixed solvent is 1:0.125-0.5:0.05-0.2.

[0019] As a preferred embodiment of the method for preparing the fluorene ring-based organic material of the present invention, wherein: in the preparation of 9-bis(3-benzoic acid)ethylene-fluorene, the molar ratio of 9-bis(3-benzoic acid methyl ester)ethylene-fluorene to sodium hydroxide is 1:1 to 15.

[0020] As a preferred embodiment of the method for preparing the fluorene ring-based organic material of the present invention, wherein: in the preparation of 9-di(3-benzoic acid)ethylene-fluorene, the volume of the mixed solvent corresponding to each 1 mmol of 9-dibromoethylene-fluorene is 50 to 400 mL.

[0021] As a preferred embodiment of the method for preparing the fluorene ring-based organic material of the present invention, the volume ratio of tetrahydrofuran to methanol and water in the mixed solvent is 1:0.5-2:0.5-2.

[0022] Beneficial effects of the present invention:

[0023] The present invention synthesizes for the first time an organic material 9-bis(3-benzoic acid)ethylene-fluorene based on a fluorene ring and containing a carboxyl group. The material has a significant aggregation-induced emission effect, and its luminescence performance is weak in benign solvents but strong in poor solvents.

[0024] The organic material 9-bis(3-benzoic acid)ethylene-fluorene of the present invention can be used to detect aqueous permanganate. At the same time, because it contains a carboxyl group, it can coordinate with more types of metals with oxygen than other fluorene compounds, and has a wider application. In addition, the preparation method is simple, the yield is high, the reaction activity is good, and it can be applied and promoted on a large scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort. Among them:

[0026] Figure 1 This is the nuclear magnetic spectrum of 9-bis(3-benzoic acid)ethylene-fluorene prepared in the present invention.

[0027] Figure 2 This is the single crystal structure diagram of 9-bis(3-benzoic acid)ethylene-fluorene prepared in the present invention.

[0028] Figure 3 . Solid fluorescence excitation and emission spectra of 9-bis(3-benzoic acid)ethylene-fluorene prepared by the present invention (excitation wavelength 341 nanometers, emission wavelength 494 nanometers).

[0029] Figure 4This is a fluorescence intensity diagram of 9-bis(3-benzoic acid)ethylene-fluorene prepared in the present invention in mixed solutions of DMF and water in different proportions.

[0030] Figure 5 This is a graph showing the change in luminescence intensity when different volumes of aqueous permanganate solution are added to an aqueous suspension of 9-bis(3-benzoate)ethylene-fluorene prepared in the present invention;

[0031] Figure 6 This is the quenching constant curve for detecting permanganate with 9-bis(3-benzoic acid)ethylene-fluorene prepared by the present invention;

[0032] Figure 7 This is the detection limit curve of 9-bis(3-benzoic acid)ethylene-fluorene prepared by the present invention for detecting permanganate. DETAILED DESCRIPTION

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the embodiments of the specification.

[0034] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0035] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0036] Example 1

[0037] This example prepares 9-bis(methyl 3-benzoate)ethylene-fluorene, specifically:

[0038] 9-Dibromoethylene-fluorene (338 mg, 1.00 mmol), 3-methoxycarbonylphenylboronic acid (360 mg, 2.00 mmol), anhydrous potassium carbonate (691 mg, 5.00 mmol), and tetrakistriphenylphosphine palladium (139 mg, 0.12 mmol) as catalyst were added to 100 mL of a mixed solvent of toluene, methanol, and water (V:V:V = 1:0.25:0.05). The mixture was heated to 110°C under nitrogen for 12 hours. After the reaction, the mixture was extracted three times with dichloromethane. The organic layer was collected, dried over anhydrous magnesium sulfate, and evaporated under reduced pressure. The crude product was obtained by column chromatography using ethyl acetate and n-hexane (V:V = 1:8) as eluents. The crude product was then washed with n-hexane to obtain a light yellow product, 9-bis(methyl 3-benzoate)ethylene-fluorene, with a calculated yield of 51%.

[0039] Example 2

[0040] This example is based on Example 1, and the various process parameters in the preparation process of 9-bis(methyl 3-benzoate)ethylene-fluorene are adjusted to explore their effects on the yield. The specific parameter adjustments and results are shown in Table 1.

[0041] Table 1 Effect of different process parameter adjustments on the yield of 9-bis(3-benzoic acid methyl ester)ethylene-fluorene

[0042]

[0043]

[0044] As can be seen from Table 1, in the preparation process of 9-bis(methyl 3-benzoate)ethylene-fluorene, the present invention can improve the yield of 9-bis(methyl 3-benzoate)ethylene-fluorene and improve the preparation efficiency by adjusting the preparation process, such as the amount of raw materials, the amount of catalyst, the solvent ratio, the temperature and the reaction time.

[0045] Example 3

[0046] This example is based on the 9-bis(3-benzoic acid methyl ester)ethylene-fluorene prepared in Example 1, and is specifically prepared as follows:

[0047] 9-bis(3-benzoic acid methyl ester)ethylene-fluorene (446 mg, 1.00 mmol) and sodium hydroxide (410 mg, 10.00 mmol) were added to 60 mL of a mixed solvent of tetrahydrofuran, methanol and water (V:V:V=1:1:1), heated to 80°C under nitrogen protection, reacted for 24 hours, and evaporated under reduced pressure. The product was acidified with hydrochloric acid to a pH <1. The precipitate was filtered out and washed with water to give a light yellow product, 9-bis(3-benzoic acid)ethylene-fluorene, with a calculated yield of 67%.

[0048] Figure 1The NMR spectrum of 9-bis(3-benzoic acid)ethylene-fluorene prepared in this example is characterized as follows:

[0049] 1H NMR(400MHz, DMSO)δ8.08(dt,J=7.4,1.6Hz,2H),8.00-7.93(m,2H),7.88(d,J=7.6Hz,2H),7.7 9-7.65(m,4H),7.31(td,J=7.5,1.0Hz,2H),6.99(td,J=7.7,1.2Hz,2H),6.43(d,J=7.9Hz,2H), Figure 2 As shown in its single crystal structure diagram, it can be seen that the present invention successfully prepared 9-bis(3-benzoic acid)ethylene-fluorene.

[0050] Example 4

[0051] This example is based on Example 3, and the various process parameters in the preparation process of 9-bis(3-benzoic acid)ethylene-fluorene are adjusted to explore their effects on the yield. The specific parameter adjustments and results are shown in Table 2.

[0052] Table 2 Effect of different process parameter adjustments on the yield of 9-bis(3-benzoic acid)ethylene-fluorene

[0053]

[0054]

[0055] Comparative Example 1

[0056] The difference between this comparative example and Example 3 is that no nitrogen was introduced during the heating reaction. The reaction was heated to 80° C. in an air atmosphere and reacted for 24 h to obtain a light yellow product, 9-di(3-benzoic acid)ethylene-fluorene, with a calculated yield of only 20%.

[0057] As can be seen from Table 2 and the results of Comparative Example 1, in the preparation process of 9-bis(3-benzoic acid)ethylene-fluorene of the present invention, the introduction of nitrogen can greatly increase the yield of the material, and by optimizing other preparation processes, such as the amount of catalyst, the solvent ratio and the heating conditions, the yield can be further increased.

[0058] Example 5

[0059] This example verifies the luminescent properties of 9-bis(3-benzoic acid)ethylene-fluorene material.

[0060] Figure 3 The solid fluorescence excitation and emission spectra of 9-bis(3-benzoic acid)ethylene-fluorene prepared in the present invention (excitation wavelength 341 nm, emission wavelength 494 nm) show that the material itself has relatively obvious luminescence characteristics.

[0061] The 9-bis(3-benzoic acid)ethylene-fluorene material was dispersed into 50 mL of a mixed solution of DMF and water in different proportions to prepare a stable suspension with a concentration of 0.1 mg / mL. The luminescence intensity was tested under 330 nm excitation light. The results are as follows: Figure 4 As shown in the figure, as the proportion of water in the mixed solution gradually increases, the luminescence intensity is significantly enhanced, which shows that the material has obvious aggregation-induced emission effect.

[0062] Example 6

[0063] This example verifies the effectiveness of the 9-bis(3-benzoic acid)ethylene-fluorene material in detecting permanganate.

[0064] The 9-bis(3-benzoic acid)ethylene-fluorene prepared in Example 3 of the present invention was dispersed in 50 mL of water to prepare a stable suspension with a concentration of 0.1 mg / mL. 5 mM permanganate aqueous solution of different volumes was added dropwise and the luminescence intensity was tested under 330 nm excitation light. The results are as follows: Figure 5 As shown in Figure 2, as the amount of permanganate increases, the luminescence intensity of the suspension gradually quenches, and the quenching efficiency reaches 95.7%. Figure 6 、 Figure 7 As shown, its quenching constant is 4.37×10 4 M -1 , the detection limit was 4.55×10 -3 mM2, indicating that the material can be effectively used in the detection of permanganate.

[0065] In summary, the present invention synthesized for the first time an organic material 9-bis(3-benzoic acid)ethylene-fluorene based on a fluorene ring and containing a carboxyl group. This material has a significant aggregation-induced emission effect, and its luminescence performance is weak in benign solvents, but strong in poor solvents.

[0066] The organic material 9-bis(3-benzoic acid)ethylene-fluorene of the present invention can be used to detect aqueous permanganate. At the same time, because it contains a carboxyl group, it can coordinate with more types of metals with oxygen than other fluorene compounds, and has a wider application. In addition, the preparation method is simple, the yield is high, the reaction activity is good, and it can be applied and promoted on a large scale.

[0067] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. The use of carboxyl-containing 9-bis(3-benzoic acid)ethylene-fluorene in the detection of permanganate in aqueous phase, characterized by: The carboxyl-containing 9-bis(3-benzoic acid)ethylene-fluorene has a structural formula as shown in Formula A; (Formula A); The 9-bis(3-benzoic acid)ethylene-fluorene is used to detect aqueous permanganate, and its quenching constant is 4.37×10 4 M -1 , the detection limit was 4.55×10 -3 mM.

2. The use of the carboxyl-containing 9-bis(3-benzoic acid)ethylene-fluorene according to claim 1 in detecting aqueous permanganate, characterized in that: The preparation method of the carboxyl-containing 9-bis(3-benzoic acid)ethylene-fluorene comprises: Preparation of 9-bis(methyl 3-benzoate)ethylene-fluorene: Dibromoethylene-fluorene, 3-methoxycarbonylphenylboronic acid, anhydrous potassium carbonate, and tetrakis(triphenylphosphine)palladium catalyst are added to a mixed solvent of toluene, methanol, and water, and heated to 60-140°C under nitrogen protection for 10-30 hours. After completion of the reaction, extraction is performed three times with dichloromethane. The organic layer is collected, dried over anhydrous magnesium sulfate, and evaporated under reduced pressure. Column chromatography is performed using ethyl acetate and n-hexane as eluents to obtain a crude product, which is then washed with n-hexane to obtain a light yellow product, namely 9-bis(methyl 3-benzoate)ethylene-fluorene. Preparation of 9-bis(3-benzoic acid)ethylene-fluorene: 9-Bis(3-benzoic acid methyl ester)ethylene-fluorene and sodium hydroxide are added to a mixed solvent of tetrahydrofuran, methanol, and water. The mixture is heated to 60-140°C under nitrogen and allowed to react for 10-30 hours. The mixture is then evaporated under reduced pressure and acidified with hydrochloric acid to a pH < 1. The precipitate is filtered and washed with water to obtain a light yellow product, 9-bis(3-benzoic acid)ethylene-fluorene, an organic material with aggregation-induced emission.

3. The use of the carboxyl-containing 9-bis(3-benzoic acid)ethylene-fluorene according to claim 2 in detecting aqueous permanganate, characterized in that: The preparation of 9-bis(3-methylbenzoate)ethylene-fluorene, wherein the molar ratio of 9-dibromoethylene-fluorene, 3-methoxycarbonylphenylboronic acid, anhydrous potassium carbonate, and tetrakis(triphenylphosphine)palladium is 1:1~5:4~6:0.1~0.

2.

4. The use of the carboxyl-containing 9-bis(3-benzoic acid)ethylene-fluorene according to claim 3 in detecting aqueous permanganate, characterized in that: The preparation of 9-bis(3-methylbenzoate)ethylene-fluorene, wherein the mixed solvent corresponding to each 1 mmol of 9-dibromoethylene-fluorene is 100 to 300 mL.

5. The use of the carboxyl-containing 9-bis(3-benzoic acid)ethylene-fluorene according to claim 2 in detecting aqueous permanganate, characterized in that: The volume ratio of toluene, methanol and water in the mixed solvent is 1:0.125~0.5:0.05~0.

2.

6. The use of the carboxyl-containing 9-bis(3-benzoic acid)ethylene-fluorene according to claim 2 in detecting aqueous permanganate, characterized in that: The preparation of 9-bis(3-benzoic acid)ethylene-fluorene, wherein the molar ratio of the 9-bis(3-benzoic acid methyl ester)ethylene-fluorene to sodium hydroxide is 1:1~15.

7. The use of the carboxyl-containing 9-bis(3-benzoic acid)ethylene-fluorene according to claim 2 in detecting aqueous permanganate, characterized in that: The preparation of 9-bis(3-benzoic acid)ethylene-fluorene, wherein the volume of the mixed solvent corresponding to each 1 mmol of 9-dibromoethylene-fluorene is 50 to 400 mL.

8. The use of the carboxyl-containing 9-bis(3-benzoic acid)ethylene-fluorene according to claim 2 in detecting aqueous permanganate, characterized in that: The volume ratio of tetrahydrofuran to methanol and water in the mixed solvent is 1:0.5~2:0.5~2.

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