Chiral recognition material as well as preparation method and application thereof

Abstract

The invention discloses a chiral recognition material and a preparation method and application thereof. The chiral recognition material disclosed by the invention is obtained by performing chemical modification by taking a dihydrodibenzophenazine derivative as a parent material, and has the functions of performing chiral recognition on a natural chiral compound by utilizing luminescence color difference and performing ee value detection on the natural chiral compound by utilizing ratio-dependent fluorescence; the chiral recognition effect is obvious, and the limitation on environmental requirements is less.

Description

Technical Field

[0001] The present invention relates to the technical field of organic luminescent materials, and in particular to a chiral recognition material and a preparation method and application thereof. Background Art

[0002] The enantiomers of natural chiral compounds often have different properties. In some specific compounds, the properties of enantiomers are even more different. It is not uncommon for one enantiomer to have a significant effect while the other enantiomer has no effect or is even toxic and harmful. Therefore, chiral identification and determination of the enantiomeric purity of natural chiral compounds are of great significance.

[0003] Light, due to its non-invasive characteristics, has become a key method to amplify the chirality of microscopic molecules to macroscopic manifestations. However, among the current methods of using luminescence for chiral identification, most of them use changes in luminescence intensity for judgment. The change in luminescence intensity is difficult to visually distinguish with the naked eye, and generally requires the use of expensive spectrometers to judge. The change in luminescence wavelength, especially the change in wavelength in the visible light band, is manifested as a change in luminescence color, which can be well captured by the human eye and is conducive to chiral identification. In addition, the current method of using light intensity changes to detect enantiomeric excess percentage (abbreviated as ee value) has high environmental requirements, and the intensity obtained in different environments often varies greatly. The use of ratio fluorescence for ee value detection can greatly reduce environmental impact and is a very promising development direction.

[0004] However, currently, there are few materials that can simultaneously use the difference in luminescent color to perform chiral recognition of natural chiral compounds and use ratiometric fluorescence to perform ee value detection of natural chiral compounds. Summary of the invention

[0005] The present application provides a chiral recognition material and a preparation method and application thereof. The chiral recognition material has the functions of both using the difference in luminescent color to perform chiral recognition on natural chiral compounds and using ratiometric fluorescence to perform ee value detection on natural chiral compounds.

[0006] In the first aspect, the present invention provides a chiral recognition material having a chemical structure shown in formula (I) or (II):

[0007]

[0008] Wherein, n represents the number of methylene groups, and n is any integer between 1 and 10. The R group has a chemical structure shown in any one of formulas (A1) to (A4):

[0009]

[0010] In some embodiments, the chiral material has a dual emission function, and the chiral recognition material has luminescence properties at wavelengths of 460 nm and 600 nm.

[0011] In some embodiments, the chiral recognition material exhibits different luminescence intensities in ethyl acetate, methanol, acetonitrile, and N,N-dimethylformamide.

[0012] In a second aspect, the present invention provides a method for preparing a chiral recognition material, comprising the following steps:

[0013] (1) preparing dihydrodibenzophenazine derivatives;

[0014] (2) Chemically modifying a dihydrodibenzophenazine derivative to obtain the chiral recognition material.

[0015] In a third aspect, the present application provides an application method of a chiral recognition material, comprising the following steps:

[0016] (1) mixing a chiral recognition material and a chiral acid in an organic solvent to obtain a mixed solution;

[0017] (2) Based on the mixed solution, detecting the type of chiral enantiomer and the enantiomeric excess percentage of the chiral acid.

[0018] In some embodiments, the organic solvent comprises at least one of cyclohexane, acetone, chloroform, dichloromethane, ethyl acetate, and tetrahydrofuran.

[0019] In some embodiments, the organic solvent includes cyclohexane and acetone, and the ratio of the cyclohexane to the acetone is 5:1 in terms of mass percentage.

[0020] In some embodiments, the ratio of the chiral recognition material to the chiral acid is 0.1-10 by mass percentage.

[0021] In some embodiments, in step (2), the chiral enantiomer type of the chiral acid is determined based on the luminescence wavelength of the mixed solution.

[0022] In some embodiments, in the step (2), the enantiomeric excess percentage of the chiral acid in the mixed solution is determined based on the ratiometric fluorescence ratio of the mixed solution.

[0023] It can be seen from the above technical scheme that the present specification provides a chiral recognition material, which is obtained by chemically modifying a dihydrodibenzophenazine derivative as a parent material, and the raw materials are pure organic compounds, which have a wide source, are easily available, are inexpensive, simple to synthesize, and convenient to prepare; and the chiral recognition material has stable luminescent properties and can be used in the air without the need for inert gas protection or a vacuum environment; in addition, the chiral recognition material has the functions of using the difference in luminescent color to perform chiral recognition on natural chiral compounds, and using ratiometric fluorescence to perform ee value detection on natural chiral compounds, and has an obvious chiral recognition effect, with few restrictions on the environment, and is suitable for chiral recognition of natural chiral compounds, enantiomeric purity analysis, and other aspects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of 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 work.

[0025] Figure 1 Fluorescence spectra of chiral recognition materials provided in some embodiments of the present application obtained when dissolved in different solvents;

[0026] Figure 2 Pictures of different mixed solutions provided in some application examples of this application after being irradiated by 365nm ultraviolet light;

[0027] Figure 3 Fluorescence spectra of different solutions provided for some application examples of this application;

[0028] Figure 4 A schematic diagram of a curve with ratio fluorescence as the ordinate and ee value as the abscissa after the chiral recognition material provided in some application examples of the present application is mixed with a chiral acid;

[0029] Figure 5 The pictures of the chiral recognition material (1S, 2R)-DPAC provided in some application examples of this application and processed by the standard colorimetric card software after being mixed with chiral acids (B-5) with different ee values;

[0030] Figure 6 The pictures of the chiral recognition material (1R, 2S)-DPAC provided in some application examples of this application and processed by the standard colorimetric card software after being mixed with chiral acids (B-5) with different ee values;

[0031] Figure 7 Pictures of different mixed solutions provided in some application examples of this application after being irradiated by 365nm ultraviolet light;

[0032] Figure 8 Fluorescence spectra of different solutions provided for some application examples of this application;

[0033] Fig. 9 Pictures of different mixed solutions provided in some application examples of this application after being irradiated by 365nm ultraviolet light;

[0034] Fig.10 Fluorescence spectra of different solutions provided for some application examples of this application. DETAILED DESCRIPTION

[0035] In order to facilitate the understanding of this specification, the specification will be described more fully below with reference to the relevant drawings. The preferred embodiments of this specification are given in the drawings. However, this specification can be implemented in many different forms without departing from the core spirit of this specification and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of this specification more thorough and comprehensive.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art to which this specification belongs. The terms used herein in this specification are only for the purpose of describing specific embodiments and are not intended to limit this specification. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0037] In the first aspect, the present invention provides a chiral recognition material having a chemical structure shown in formula (I) or (II):

[0038]

[0039] Wherein, n represents the number of methylene groups, and n is any integer between 1 and 10. The R group has a chemical structure shown in any one of formulas (A1) to (A4):

[0040]

[0041] The chiral recognition material provided in the embodiment of the present application has a dual emission function, and has luminescence characteristics at 460nm and 600nm. In addition, when the chiral recognition material is dissolved in different solvent systems, the corresponding fluorescence intensities at the above two emission wavelengths are different, that is, the difference in solvent systems may affect the fluorescence emission intensity of the chiral recognition material.

[0042] In some embodiments, the chiral recognition material exhibits different luminescence intensities in ethyl acetate, methanol, acetonitrile, and N,N-dimethylformamide, and the absolute fluorescence quantum yield of the chiral recognition material is ≥0.1%.

[0043] In a second aspect, the present invention provides a method for preparing a chiral recognition material, comprising the following steps:

[0044] (1) Preparation of dihydrodibenzophenazine derivatives. The chemical reaction equation involved in the process of preparing dihydrodibenzophenazine derivatives can be as follows:

[0045]

[0046] (2) Chemically modifying the dihydrodibenzophenazine derivative to obtain a chiral recognition material. The chemical reaction equation for chemical modification using the dihydrodibenzophenazine derivative as the parent is as follows:

[0047]

[0048] In the above synthesis process, compound 2 is a dihydrodibenzophenazine derivative, compound 3 is a synthesized chiral recognition material, and the chemical structure of the chiral recognition material is consistent with formula (I), and the modified group is formula (A1). It should be understood that if in the above synthesis process, compound 1 containing only one hydroxyl group is used as a reaction raw material, the chiral recognition material shown in formula (II) can be synthesized according to the above synthesis route.

[0049] In a third aspect, an embodiment of the present application provides an application method of a chiral recognition material, comprising the following steps: (1) mixing a chiral recognition material and a chiral acid in an organic solvent to obtain a mixed solution; and (2) based on the mixed solution, detecting the type of chiral enantiomer and the enantiomeric excess percentage of the chiral acid.

[0050] Wherein, the chiral acid can be selected from any one of the compounds of formula (B-1) to (B-25):

[0051]

[0052]

[0053] In some embodiments, the organic solvent includes at least one of cyclohexane, acetone, chloroform, dichloromethane, ethyl acetate and tetrahydrofuran. In the embodiment of the present application, after the chiral recognition material and the chiral acid are mixed in the above organic solvent, the obtained mixed solution can be subjected to a luminescence color difference test to achieve chiral recognition of the natural chiral compound; and the obtained mixed solution can also be subjected to ratiometric fluorescence detection to determine the ee value of the natural chiral compound.

[0054] In some embodiments, the organic solvent includes cyclohexane and acetone, and the ratio of cyclohexane to acetone is 5: 1 in terms of mass percentage. The inventors have found through a large number of experiments that a mixed solvent is obtained by mixing cyclohexane and acetone in the above ratio, and after dissolving the chiral recognition material and the chiral acid in the mixed solvent, the chiral recognition of the natural chiral compound is performed by using the difference in luminescent color, and the ee value of the natural chiral compound is detected by using ratiometric fluorescence, which can show a strong detection signal, a high signal responsiveness, and improve the detection accuracy.

[0055] In some embodiments, the ratio of the chiral recognition material to the chiral acid is 0.1-10 by mass percentage. When the chiral recognition material is used to perform the above detection on the chiral acid, the amount of both added has a certain influence on the detection result. Too much or too little addition of any one substance will cause the signal to weaken, affecting the accuracy of the detection result. The inventors have found through experiments that controlling the ratio of the chiral recognition material to the chiral acid within the range of 0.1-10 can keep the detection signal at a good level.

[0056] In some embodiments, in step (2), the chiral enantiomer species of the chiral acid is determined based on the emission wavelength of the mixed solution.

[0057] In some embodiments, in step (2), the enantiomeric excess percentage of the chiral acid in the mixed solution is determined based on the ratiometric fluorescence ratio of the mixed solution.

[0058] The following are specific preparation examples involved in the above content of the present disclosure. It should be clear that the following examples are only for illustrating the two-component doped optical materials and their preparation methods and applications disclosed above, and the specific implementation methods and parameters used therein are only one or several methods in accordance with the many processes and methods described above. Those skilled in the art can use other parameters according to the content introduced in this specification to prepare two-component doped optical materials according to the above method without deviating from the core spirit disclosed in the application.

[0059] Example 1

[0060] This embodiment provides a chiral recognition material, comprising the following steps:

[0061] (1) Preparation of dihydrodibenzophenazine derivatives. The chemical reaction equation involved in the process of preparing dihydrodibenzophenazine derivatives can be as follows:

[0062]

[0063] Compound 1 (300 mg, 0.61 mmol, 1 eq) was dissolved in 20 mL of ultra-dry tetrahydrofuran, and 2-bromoethanol (1.51 g, 12.1 mmol, 20 eq) and p-toluenesulfonic acid (115.5 mg, 0.67 mmol, 1.1 eq) were added, and the mixture was stirred at room temperature for 3 hours. After the reaction, the solvent was removed in vacuo, the mixture was quenched with water, and the organic layer was extracted with ethyl acetate, dried over anhydrous magnesium sulfate, filtered and concentrated, and purified by silica gel column chromatography (petroleum ether: ethyl acetate = 2:1) to obtain 350 mg of a white solid (compound 2). Compound 2 is a dihydrodibenzophenazine derivative with a mass of , and a yield of 81.2%.

[0064] (2) Chemically modifying the dihydrodibenzophenazine derivative to obtain a chiral recognition material. The chemical reaction equation for chemical modification using the dihydrodibenzophenazine derivative as the parent is as follows:

[0065]

[0066] Compound 2 (400 mg, 0.56 mmol, 1 eq), (1S,2R)-2-amino-1,2-diphenylethanol (481 mg, 2.26 mmol, 4 eq) and K2CO3 (232.2 mg, 1.68 mmol, 3 eq) were added to ultra-dry acetonitrile (100 ml), and the mixture was stirred and refluxed at 50°C for 10 hours. After the reaction was completed, the reactants were quenched with water, and the organic layer was extracted with dichloromethane, dried over anhydrous magnesium sulfate, filtered, concentrated, and purified by silica gel column chromatography (dichloromethane: methanol = 10:1) to obtain 210 mg of a white solid (compound 3), which was the chiral recognition material, with a yield of 38.6%.

[0067] The chiral recognition material prepared in Example 1 was dissolved in ethyl acetate (EA), methanol (MeOH), acetonitrile (MeCN), and N,N-dimethylformamide (DMF) respectively, and the fluorescence luminescence of the solution was detected. Figure 1 The fluorescence spectra of the chiral recognition material prepared in Example 1 dissolved in different solvents are shown, wherein the abscissa is the wavelength and the ordinate is the intensity. Figure 1 As shown, the chiral recognition material has dual emission function, showing luminescence characteristics at wavelengths of 460nm and 600nm respectively. In addition, the chiral recognition material will show different luminescence intensities in different solvents (such as ethyl acetate, methanol, acetonitrile, N,N-dimethylformamide).

[0068] Application Example 1

[0069] The chiral recognition material prepared in Example 1 has two enantiomers, which are respectively represented as (1S, 2R)-DPAC and (1R, 2S)-DPAC for easy distinction.

[0070] In this application example, the chiral recognition material is used to recognize the chiral acid (B-5).

[0071] Cyclohexane and acetone were prepared into a mixed solvent in a mass ratio of 5:1, (1S, 2R)-DPAC was dissolved in the mixed solvent, and two chiral enantiomers RB-5 and SB-5 of the chiral acid (B-5) were added to the mixed solvent respectively to obtain mixed solution 1 and mixed solution 2, wherein the chiral enantiomer RB-5 was added to the mixed solution 1, and the chiral enantiomer SB-5 was added to the mixed solution 2.

[0072] The mixed solution 1 and the mixed solution 2 were irradiated with 365 nm ultraviolet light. Figure 2 The following are pictures of the two mixed solutions in Application Example 1 after being irradiated by a 365nm ultraviolet lamp. Figure 2 As shown, for chiral acids of different configurations, after mixing them with chiral recognition materials, obvious differences in luminescent colors can be observed with the naked eye after irradiation with 365nm ultraviolet light.

[0073] The fluorescence luminescence of mixed solution 1 and mixed solution 2 is detected. Figure 3 The fluorescence spectra of different solutions in Application Example 1 are shown, wherein the horizontal axis is the wavelength and the vertical axis is the intensity. Figure 3 As shown in the figure, compared with the case where only (1S,2R)-DPAC exists, obvious wavelength differences can be observed after mixing (1S,2R)-DPAC with chiral acid; and different mixed solutions also have obvious wavelength differences. Figure 2 , Figure 3 It can be confirmed from the phenomenon that the chiral recognition material prepared in Example 1 can be used for chiral recognition of natural chiral compounds.

[0074] The same equivalent of (1S,2R)-DPAC and (1R,2S)-DPAC were mixed with chiral acid (B-5) with different ee values, respectively, to obtain two curves with ratio fluorescence as the horizontal axis and ee value as the vertical axis. Figure 4 The figure shows a curve schematic diagram of the chiral recognition material and the chiral acid mixed in Application Example 1, with the ratio fluorescence as the ordinate and the ee value as the abscissa. Figure 4 As shown in the figure, at different ee values, the ratio fluorescence of chiral recognition materials is different. Figure 4 The curve shown allows for ee value detection of chiral acids based on ratiometric fluorescence of unknown ee values.

[0075] Figure 5 The images are shown after (1S, 2R)-DPAC in Application Example 1 is mixed with chiral acids (B-5) of different ee values ​​and processed by standard colorimetric card software. Figure 6 The following are pictures of (1R,2S)-DPAC and chiral acids (B-5) with different ee values ​​mixed in Application Example 1 and processed by the standard colorimetric card software. As the ee value changes, the color of the mixed solution can be observed to change with the naked eye.

[0076] Application Example 2

[0077] In this application example, the chiral recognition material is used to recognize the chiral acid (B-11).

[0078] Cyclohexane and acetone were prepared into a mixed solvent in a mass ratio of 5:1, (1S, 2R)-DPAC was dissolved in the mixed solvent, and two chiral enantiomers RB-11 and SB-11 of the chiral acid (B-11) were added to the mixed solvent respectively to obtain mixed solution 3 and mixed solution 4, wherein the chiral enantiomer RB-11 was added to the mixed solution 3, and the chiral enantiomer SB-11 was added to the mixed solution 4.

[0079] The mixed solution 3 and the mixed solution 4 are irradiated with 365 nm ultraviolet light. Figure 7 The following are pictures of the two mixed solutions in Application Example 2 after being irradiated by a 365nm ultraviolet lamp. Figure 7 As shown, for chiral acids of different configurations, after mixing them with chiral recognition materials, obvious differences in luminescent colors can be observed with the naked eye after irradiation with 365nm ultraviolet light.

[0080] The fluorescence luminescence of mixed solution 3 and mixed solution 4 was detected. Figure 8 FIG. 2 shows the fluorescence spectra of different solutions in Application Example 2, wherein the horizontal axis is the wavelength and the vertical axis is the intensity. Figure 8 As shown in the figure, compared with the case where only (1S,2R)-DPAC exists, obvious wavelength differences can be observed after mixing (1S,2R)-DPAC with chiral acid; and different mixed solutions also have obvious wavelength differences. Figure 7 , Figure 8 It can be confirmed from the phenomenon that the chiral recognition material prepared in Example 1 can be used for chiral recognition of natural chiral compounds.

[0081] Application Example 3

[0082] In this application example, the chiral recognition material is used to recognize the chiral acid (B-20).

[0083] Cyclohexane and acetone were prepared into a mixed solvent in a mass ratio of 5:1, (1S, 2R)-DPAC was dissolved in the mixed solvent, and two chiral enantiomers RB-20 and SB-20 of the chiral acid (B-20) were added to the mixed solvent respectively to obtain mixed solution 5 and mixed solution 6, wherein the chiral enantiomer RB-20 was added to the mixed solution 5, and the chiral enantiomer SB-20 was added to the mixed solution 6.

[0084] The mixed solution 5 and the mixed solution 6 are irradiated with 365 nm ultraviolet light. Fig. 9 The following are pictures of the two mixed solutions in Application Example 3 after being irradiated by a 365nm ultraviolet lamp. Fig. 9 As shown, for chiral acids of different configurations, after mixing them with chiral recognition materials, obvious differences in luminescent colors can be observed with the naked eye after irradiation with 365nm ultraviolet light.

[0085] The mixed solution 5 and the mixed solution 6 are tested for fluorescence emission. Fig.10 FIG. 4 shows the fluorescence spectra of different solutions in Application Example 3, wherein the horizontal axis is the wavelength and the vertical axis is the intensity. Fig.10 As shown in the figure, compared with the case where only (1S,2R)-DPAC exists, obvious wavelength differences can be observed after mixing (1S,2R)-DPAC with chiral acid; and different mixed solutions also have obvious wavelength differences. Fig. 9 , Fig.10 It can be confirmed from the phenomenon that the chiral recognition material prepared in Example 1 can be used for chiral recognition of natural chiral compounds.

[0086] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0087] The above-described embodiments only express several embodiments of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. It should be understood that the technical solutions obtained by those skilled in the art through logical analysis, reasoning or limited experiments on the basis of the technical solutions provided by the present invention are all within the protection scope of the claims attached to the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims, and the description and drawings may be used to interpret the contents of the claims.

Claims

1. A chiral recognition material, characterized in that: It has a chemical structure shown in formula (I) or (II): Wherein, n represents the number of methylene groups, and n is any integer between 1 and 10. The R group has a chemical structure shown in any one of formulas (A1) to (A4):

2. The chiral recognition material according to claim 1, characterized in that The chiral material has a dual emission function, and the chiral recognition material has luminescence characteristics at wavelengths of 460nm and 600nm.

3. The chiral recognition material according to claim 1, characterized in that The chiral recognition material exhibits different luminescence intensities in ethyl acetate, methanol, acetonitrile and N,N-dimethylformamide.

4. A method for preparing a chiral recognition material, characterized in that: The following steps are involved: (1) preparing dihydrodibenzophenazine derivatives; (2) Chemically modifying a dihydrodibenzophenazine derivative to obtain the chiral recognition material.

5. A method for applying a chiral recognition material, characterized in that: The following steps are involved: (1) mixing a chiral recognition material and a chiral acid in an organic solvent to obtain a mixed solution; (2) Based on the mixed solution, detecting the type of chiral enantiomer and the enantiomeric excess percentage of the chiral acid.

6. The method for applying the chiral recognition material according to claim 5, characterized in that: The organic solvent includes at least one of cyclohexane, acetone, chloroform, dichloromethane, ethyl acetate and tetrahydrofuran.

7. The method for applying the chiral recognition material according to claim 6, characterized in that: The organic solvent includes cyclohexane and acetone, and the ratio of the cyclohexane to the acetone is 5:1 in terms of mass percentage.

8. The method for applying the chiral recognition material according to claim 5, characterized in that: In terms of mass percentage, the ratio of the chiral recognition material to the chiral acid is 0.1-10.

9. The method for applying the chiral recognition material according to claim 5, characterized in that: In the step (2), the chiral enantiomer type of the chiral acid is determined based on the luminescence wavelength of the mixed solution.

10. The method for applying the chiral recognition material according to claim 5, characterized in that: In the step (2), the enantiomeric excess percentage of the chiral acid in the mixed solution is determined based on the ratiometric fluorescence ratio of the mixed solution.

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