Nitrogen-containing heterocyclic ring organic compound with room-temperature phosphorescence performance as well as preparation method and application of nitrogen-containing heterocyclic ring organic compound
By designing and preparing pure organic compounds with nitrogen-containing heterocyclic structures, the problem that pure organic compounds in the prior art are difficult to emit phosphorescence at room temperature is solved, and the effect of high phosphorescence efficiency and long life is achieved, which is suitable for a variety of application fields.
Patent Information
- Application Number
- CN202410219909.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-02-28
- Publication Date
- 2025-03-07
AI Technical Summary
In the prior art, pure organic compounds are difficult to effectively emit phosphorescence at room temperature due to spin resistance and non-radiative transitions, and the high cost and scarcity of metal materials limit their popularity and development.
By introducing nitrogen-containing heterocyclic structures and introducing different substituent groups by chemical modification methods, a class of pure organic compounds with room temperature phosphorescence properties are designed, and the general formula of which is a specific pyridine derivative. The compound is prepared by a specific reaction step, including the reaction of compound A-4 with compound A-3, followed by reaction with compound R1H, to form a compound with high phosphorescence efficiency and long lifetime.
It has achieved high phosphorescence efficiency and long life pure organic room temperature phosphorescence compounds. Its materials are easy to obtain, simple preparation, fast separation and purification, and are suitable for multiple anti-counterfeiting, chemical sensing and biological imaging fields.
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Figure CN119569719A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of organic luminescent materials, and in particular to a class of nitrogen-containing heterocyclic organic compounds with room temperature phosphorescence properties, and a preparation method and application thereof. Background Art
[0002] Generally speaking, the luminescence that can still be seen by the human eye after the excitation stops is called phosphorescence. Organic phosphorescent materials are mainly used in anti-counterfeiting, information encryption, oxygen sensing and mapping, stimulus response equipment and high-contrast bio-imaging, and are very popular. According to the previous discovery of the phosphorescent electroluminescence phenomenon of platinum metal organic complex molecules at room temperature, compared with previous fluorescent materials, its luminescence efficiency is extremely high. This is because it enhances the spin-orbit coupling effect through heavy metal atoms, so that the singlet exciton can cross to the triplet state through intersystem crossing, and then return to the ground state through radiation transition from the triplet state to emit phosphorescence, achieving 100% exciton utilization.
[0003] However, the metal materials used are very expensive and scarce, which is not conducive to its popularization and development. In addition, pure organic compounds cannot effectively produce triplet excitons due to spin prohibition, and it is difficult to emit phosphorescence at room temperature. In addition, due to non-radiative transitions and exciton quenching, this affects the luminescence efficiency of phosphorescence.
[0004] However, recent studies have shown that room temperature phosphorescence emission of pure organic compounds can be achieved by means of crystallization, deuteration, H-aggregation, doping, and the introduction of a rigid framework. The introduction of halogens, carbonyls, heterocyclic compounds, and boric acid (ester) groups allows intersystem crossing from singlet to triplet states, while deuteration, H-aggregation, doping, and the like can increase molecular rigidity and reduce the non-radiative inactivation of triplet states. Therefore, a pyridine ring containing a N heteroatom is provided as a basic unit, and different substituent groups are introduced by chemical modification to obtain a series of pyridine derivatives with different phosphorescence efficiencies and phosphorescence lifetimes. This type of pure organic room temperature phosphorescent material has broad application potential in the fields of security, anti-counterfeiting, encryption, and biological imaging. Summary of the invention
[0005] In view of the above problems, the purpose of the present invention is to provide a class of pure organic room temperature phosphorescent compounds with high phosphorescence efficiency and long life. Such compounds have high phosphorescence efficiency and long life, and the materials are easy to obtain, the preparation is simple, and the separation and purification are fast, so they are efficient phosphorescent materials.
[0006] Another object of the present invention is to apply the above-mentioned pure organic room temperature phosphorescent compound with high phosphorescence efficiency and long life to the fields of multiple anti-counterfeiting, chemical sensing, biological imaging, etc.
[0007] To achieve the above object, the present invention provides a class of nitrogen-containing heterocyclic organic compounds with room temperature phosphorescence properties, having a general structural formula shown in Formula A:
[0008]
[0009] Wherein, R1 is an electron-donating group selected from one of the groups shown;
[0010]
[0011] Wherein, the dotted line (--) indicates the connection site with another unit;
[0012] In the above structure of R1, R is the same or different and is independently selected from hydrogen, C1-15 alkyl, halogenated C1-15 alkyl, C1-15 alkoxy, halogenated C1-15 alkoxy, C3-20 cycloalkyl, C6-20 aryl, 5-20 membered heteroaryl, 3-20 membered heterocyclyl;
[0013] R2 and R3 in the general formula A are the same or different and are independently selected from H, C1-15 alkyl, C3-20 cycloalkyl, C6-20 aryl, 5-20 membered heteroaryl, 3-20 membered heterocyclyl.
[0014] Preferably, in formula A, R1 is selected from the following structures:
[0015]
[0016] wherein R is selected from H;
[0017] In formula A, R2 and R3 are independently selected from methyl groups.
[0018] Preferably, the structure shown in formula A is selected from the following:
[0019]
[0020] The present invention also provides a method for preparing a class of nitrogen-containing heterocyclic organic compounds having room temperature phosphorescence properties. The nitrogen-containing heterocyclic organic compounds are prepared by the following reaction:
[0021]
[0022] (1) Compound A-4 reacts with compound A-3 to obtain compound A-2;
[0023] (2) Compound A-2 reacts with compound R1H to obtain compound A-1;
[0024] Wherein, X1 is selected from leaving groups including fluorine, chlorine, bromine and iodine; and X2 is selected from cyano.
[0025] Preferably, a method for preparing an organic compound having room temperature phosphorescence performance comprises the following steps:
[0026] 1) adding a base and a carbazole to an organic solvent under nitrogen protection to carry out a dissolution reaction to obtain a reaction solution;
[0027] 2) dissolving the reactant pyridine derivative in an organic solvent and adding it to the reaction solution of step 1), heating to 70-130° C. for reaction, and cooling to room temperature after the reaction is completed.
[0028] 3) The reaction solution was poured into ice water and filtered. The residue was dissolved with dichloromethane and dried with anhydrous sodium sulfate. The filtrate was mixed with silica gel and passed through a column to obtain the product.
[0029] Preferably, the base in step 1) is potassium carbonate, sodium carbonate, cesium carbonate, potassium tert-butoxide, sodium tert-butoxide or sodium hydride; the carbazole is carbazole or phenylcarbazole; the organic solvent is N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, toluene, 1,4-dioxane or tetrahydrofuran; and the pyrazole derivative is shown as A-2.
[0030] The invention also provides an application of an organic compound with room temperature phosphorescence performance in the field of multi-level anti-counterfeiting encryption.
[0031] The invention also provides an application of an organic compound with room temperature phosphorescence performance in the field of biological imaging.
[0032] Therefore, the present invention adopts the above-mentioned nitrogen-containing heterocyclic organic compound with room temperature phosphorescence performance and its preparation method and application, and has the following beneficial effects:
[0033] (1) The present invention combines N-pyridine and oxazoline derivatives with carbazole, phenylcarbazole and other groups to obtain compounds with strong room temperature phosphorescence properties. The synthesis is not only simple but also efficient, and does not require the use of catalysts such as precious metals. The preparation method is simple, the materials are cheap and easy to obtain, and the reaction conditions are mild, and it is easy to separate and purify.
[0034] (2) This type of organic room temperature phosphorescent material containing N-pyridine heterocycle has high phosphorescence quantum efficiency and long lifespan. The lifespan of carbazole of formula 1 can reach 4.64s, and its phosphorescence quantum efficiency can reach 7.44%. Its fluorescence and phosphorescence colors are blue and yellow respectively, with obvious distinguishing effects. It is an ideal material for realizing multiple anti-counterfeiting encryption, biological imaging, etc.
[0035] (3) By adjusting the steric hindrance and conjugation degree of the ligands on the nitrogen-containing heterocycles, adjusting the type of donor to change the strength of electron donation, etc., the luminescence properties of such nitrogen-containing heterocycles can be controlled.
[0036] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS
[0037] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.
[0038] Figure 1 is a comparison diagram of the absorption spectra of the compounds obtained by formula 1 and formula 2 in dichloromethane solution;
[0039] Figure 2 This is a comparison of the steady-state luminescence spectrum and phosphorescence spectrum of the crystalline state of Formula 1
[0040] Figure 3 is a phosphorescence lifetime kinetic decay curve diagram of the compound crystal obtained by formula 1 at room temperature;
[0041] Figure 4 This is a picture showing the effect of irradiating the sample with a 365nm ultraviolet lamp in Example 3;
[0042] Figure 5 This is a picture of the sample effect after turning off the ultraviolet light in Example 3. DETAILED DESCRIPTION
[0043] The technical scheme of the present invention will be further described in detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only exemplary descriptions and explanations of the present invention and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are included in the scope that the present invention is intended to protect.
[0044] Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available or can be prepared by known methods.
[0045] The present invention provides a class of nitrogen-containing heterocyclic organic compounds with room temperature phosphorescence properties, having a general structural formula shown in formula A:
[0046]
[0047] Wherein, R1 is an electron-donating group selected from one of the groups shown;
[0048]
[0049] Wherein, the dotted line (--) indicates the connection site with another unit;
[0050] In the above structure of R1, R is the same or different and is independently selected from hydrogen, C1-15 alkyl, halogenated C1-15 alkyl, C1-15 alkoxy, halogenated C1-15 alkoxy, C3-20 cycloalkyl, C6-20 aryl, 5-20 membered heteroaryl, 3-20 membered heterocyclyl;
[0051] R2 and R3 in the general formula A are the same or different and are independently selected from H, C1-15 alkyl, C3-20 cycloalkyl, C6-20 aryl, 5-20 membered heteroaryl, 3-20 membered heterocyclyl.
[0052] Wherein, as a preferred structure, in formula A, R1 is selected from the following structures:
[0053]
[0054] wherein R is selected from H;
[0055] In formula A, R2 and R3 are independently selected from methyl;
[0056] Then the structure shown in formula A is selected from the following:
[0057]
[0058] The present invention also provides a method for preparing a class of nitrogen-containing heterocyclic organic compounds having room temperature phosphorescence properties. The nitrogen-containing heterocyclic organic compounds are prepared by the following reaction:
[0059]
[0060] (1) Compound A-4 reacts with compound A-3 to obtain compound A-2;
[0061] (2) Compound A-2 reacts with compound R1H to obtain compound A-1;
[0062] Wherein, X1 is selected from leaving groups including fluorine, chlorine, bromine and iodine; and X2 is selected from cyano.
[0063] A method for preparing an organic compound having room temperature phosphorescence performance comprises the following steps:
[0064] 1) adding a base and a carbazole to an organic solvent under nitrogen protection to carry out a dissolution reaction to obtain a reaction solution;
[0065] 2) dissolving the reactant pyridine derivative in an organic solvent and adding it to the reaction solution of step 1), heating to 70-130° C. for reaction, and cooling to room temperature after the reaction is completed.
[0066] 3) The reaction solution was poured into ice water and filtered. The residue was dissolved with dichloromethane and dried with anhydrous sodium sulfate. The filtrate was mixed with silica gel and passed through a column to obtain the product.
[0067] Preferably, the base in step 1) is potassium carbonate, sodium carbonate, cesium carbonate, potassium tert-butoxide, sodium tert-butoxide or sodium hydride; the carbazole is carbazole or phenylcarbazole; the organic solvent is N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, toluene, 1,4-dioxane or tetrahydrofuran; and the pyrazole derivative is shown as A-2.
[0068] The invention also provides an application of an organic compound with room temperature phosphorescence performance in the field of multi-level anti-counterfeiting encryption.
[0069] The invention also provides an application of an organic compound with room temperature phosphorescence performance in the field of biological imaging.
[0070] Example 1
[0071] Preparation of Formula 1:
[0072]
[0073] Synthesis method of the compound of the structure shown: Under nitrogen atmosphere, 2-bromo-6-cyanopyridine (10 mmol, 1.83 g) and 2-amino-2-methyl-1-propanol (10 mmol, 0.89 g) were dissolved in 5 ml of dry o-dichlorobenzene solvent, and the mixture was stirred and refluxed at 100°C for 12 h. After the temperature dropped to room temperature, the o-dichlorobenzene solvent was evacuated with a vacuum pump, and a white transparent solid (1.02 g, 40%) was obtained after column separation.
[0074] Under nitrogen atmosphere, the raw material (4mmol, 1.02g) and carbazole (4.4mmol, 0.73g) obtained in the previous step, potassium carbonate (8mmol, 1.105g), cuprous iodide (0.4mmol, 0.076g) and o-phenanthroline (0.4mmol, 0.072g) were dissolved in 20ml of dry N,N-dimethylformamide, stirred and refluxed at 150°C for 24 hours, and after cooling to room temperature, extracted three times with dichloromethane in saturated brine, dried, and the crude product was separated by column to obtain a white solid (0.572g, 42%). 1HNMR (400MHz, DMSO-d6) δ8.26(s,3H),8.03(s,1H),7.97(s,1H),7.89(d,J=8.3Hz,2H),7.49(s,2H),7.35(s,2H),4.21(s,2H),1.34(s,6H).
[0075] Preparation of Formula 2:
[0076]
[0077] Synthesis method of the compound of the structure shown: The first step is the same synthesis method as in Example 1.
[0078] Under nitrogen atmosphere, the raw material (4mmol, 1.02g) obtained in the previous step and 4-(9-carbazolyl)phenylboronic acid (6mmol, 1.72g), potassium carbonate (8mmol, 1.105g) and palladium acetate (0.06mmol, 0.012g) were dissolved in 48ml of distilled water and 144ml of ethanol, and stirred and refluxed at 80°C for 1 hour. After cooling to room temperature, the mixture was extracted three times with ethyl acetate in saturated brine and dried. The crude product was separated by column to obtain a white solid (0.650g, 39%). 1H NMR (400MHz, DMSO-d6) δ8.43(d,J=8.1Hz,2H),8.27(t,J=6.4Hz,3H),8.07(t,J=7.8Hz,1H),7.99(d,J= 7.7Hz,1H),7.81(d,J=8.3Hz,2H),7.48(q,J=7.7Hz,4H),7.35–7.28(m,2H),4.22(s,2H),1.35(s,6H).
[0079] Example 2
[0080] Cultivation of single crystals: Weigh the compound prepared in Example 2 (0.1 mmol, 0.0417 g) and dissolve it in 3 ml of dichloromethane solution. Stir it at room temperature for 1 hour, then take it out with a syringe. After filtering the solid, spread a layer of ether on it and recrystallize it. After a few days, compound crystals were obtained with a yield of 65%.
[0081] The above is an explanation of the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
[0082] Example 3
[0083] Preparation of double encryption anti-counterfeiting pattern: Under 365nm ultraviolet light, the structure shown in formula I and another material with similar luminescence are prepared as follows Figure 4 First, the structure powder of the long-life room temperature phosphorescent material formula I is used to form a pattern of the number 2, and then the short-life compound is added to make the whole pattern into a pattern of the number 8. When irradiated with a 365nm ultraviolet light, a blue pattern of the number 8 is displayed. After the ultraviolet light is turned off, only the yellow pattern of the number 2 is displayed, as shown in FIG. Figure 5 As shown. The patterns we prepared demonstrate the practical application of this type of material in security encryption and anti-counterfeiting.
[0084] The room temperature phosphorescence properties of the compound crystals obtained in Example 1 are shown in the following table:
[0085] Compound Lifespan τRTP Phosphorescence emission wavelength λ Phosphorescence quantum efficiency Φ Formula 1 0.413s 554nm 7.44％
[0086] As can be seen from the table above, the synthesized compound has a longer room temperature phosphorescence lifetime and a higher phosphorescence quantum efficiency, with the lifetime reaching 400ms and the phosphorescence quantum efficiency reaching 7.44%.
[0087] Therefore, the present invention provides a class of pure organic room temperature phosphorescent compounds with high phosphorescence efficiency and long life. Such compounds have high phosphorescence efficiency and long life, and the materials are easily available, the preparation is simple, and the separation and purification are fast, so they are efficient phosphorescent materials.
[0088] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.
Claims
1. A nitrogen-containing heterocyclic organic compound having room temperature phosphorescence properties, characterized in that: It has the general structural formula shown in formula A: Wherein, R1 is an electron-donating group selected from one of the groups shown; Wherein, the dotted line (--) indicates the connection site with another unit; In the above structure of R1, R is the same or different and is independently selected from hydrogen, C1-15 alkyl, halogenated C1-15 alkyl, C1-15 alkoxy, halogenated C1-15 alkoxy, C3-20 cycloalkyl, C6-20 aryl, 5-20 membered heteroaryl, 3-20 membered heterocyclyl; R2 and R3 in the general formula A are the same or different and are independently selected from H, C1-15 alkyl, C3-20 cycloalkyl, C6-20 aryl, 5-20 membered heteroaryl, 3-20 membered heterocyclyl.
2. The nitrogen-containing heterocyclic organic compound having room temperature phosphorescence according to claim 1, characterized in that: In formula A, R1 is selected from the following structures: wherein R is selected from H; In formula A, R2 and R3 are independently selected from methyl groups.
3. The nitrogen-containing heterocyclic organic compound having room temperature phosphorescence according to claim 2, characterized in that: The structure shown in formula A is selected from the following:
4. The method for preparing a nitrogen-containing heterocyclic organic compound having room temperature phosphorescence according to claim 1, characterized in that: The nitrogen-containing heterocyclic organic compound is prepared by the following reaction: (1) Compound A-4 reacts with compound A-3 to obtain compound A-2; (2) Compound A-2 reacts with compound R1H to obtain compound A-1; Wherein, X1 is selected from leaving groups including fluorine, chlorine, bromine and iodine; and X2 is selected from cyano.
5. The method for preparing an organic compound having room temperature phosphorescence according to claim 4, characterized in that: The steps include: 1) adding a base and a carbazole to an organic solvent under nitrogen protection to carry out a dissolution reaction to obtain a reaction solution; 2) dissolving the reactant pyridine derivative in an organic solvent and adding it to the reaction solution of step 1), heating to 70-130° C. for reaction, and cooling to room temperature after the reaction is completed. 3) The reaction solution was poured into ice water and filtered. The residue was dissolved with dichloromethane and dried with anhydrous sodium sulfate. The filtrate was mixed with silica gel and passed through a column to obtain the product.
6. The method for preparing an organic compound having room temperature phosphorescence according to claim 5, characterized in that: The base described in step 1) is potassium carbonate, sodium carbonate, cesium carbonate, potassium tert-butoxide, sodium tert-butoxide or sodium hydride; the carbazole is carbazole or phenylcarbazole; the organic solvent is N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, toluene, 1,4-dioxane or tetrahydrofuran; the pyrazole derivative is shown as A-2.
7. Application of the organic compound with room temperature phosphorescence property as described in any one of claims 1 to 6 in the field of multi-level anti-counterfeiting encryption.
8. Application of the organic compound with room temperature phosphorescence property as claimed in any one of claims 1 to 6 in the field of biological imaging.