CN116589377A - A kind of 4,4'-azodibenzoic acid ethylenediamine dye eutectic and preparation method thereof - Google Patents

Abstract

The invention discloses a 4,4' -azo-bis-benzoic acid ethylenediamine dye eutectic with a molecular formula of C ₃₀ H ₂₄ N ₆ O ₈ The structural formula isThe preparation method specifically comprises the following steps: (1) 4,4' -azobisbenzoic acid, ethylenediamine and solvent are put into a reaction vessel together under the airtight conditionPlacing the mixture on a stirrer for stirring and fully reacting; (2) Sealing the mouth of the reaction vessel with tinfoil, punching a plurality of small holes on the tinfoil with a needle, standing for volatilization, and obtaining the red transparent blocky crystal after the red transparent blocky crystal begins to be separated out from the reaction vessel. Compared with the dye, the dye eutectic of the invention has obviously improved thermal stability, and the fluorescence intensity of the dye eutectic of the invention is improved by 5 times compared with the dye, thus greatly solving the problems of the original dye in stability and fluorescence intensity.

Description

A kind of 4,4'-azodibenzoic acid ethylenediamine dye eutectic and its preparation method

technical field

The invention relates to the technical field of solid-state dye eutectics, in particular to a 4,4'-azodibenzoic acid ethylenediamine dye eutectic and a preparation method thereof.

Background technique

In 1894, E. Fischer of Germany proposed the "lock-key" model based on the idea of "selective interaction between molecules", which was the prototype of modern supramolecular science theory. In 1937, German K.L.Wolf et al. created the term "supramolecular" to describe highly ordered entities formed by the association of molecules. In a general sense, any collection of molecules has interactions, so people often refer to the structural level of material aggregation as "supramolecules". It was not until 1978 that French professor J.M. Lehn finally proposed the complete concept of "supramolecular chemistry" based on the traditional research on host-guest systems rooted in organic chemistry.

Supramolecular chemistry is a science that studies complex and ordered molecular aggregates with specific structures and functions formed by the conclusion of intermolecular interactions. . Therefore, the basis of supramolecular chemistry is the non-covalent bond interaction between molecules, and the science of functional systems formed by the non-covalent bond interaction between multiple different kinds of molecules.

Supramolecular chemistry has the following notable features: a. The strong binding force that forms supramolecular compounds is the result of the superposition and synergy of weak interaction forces between different molecules, and is a comprehensive expression of various forces; b. It is formed by the self-assembly of different molecules Supramolecular compounds show new functions that are completely different from the original self-assembled molecules. Molecular recognition and supramolecular self-assembly through the synergy of intermolecular weak interactions are the core parts of supramolecular chemistry research.

Crystal engineering applies the principles and methods of supramolecular chemistry to the design and growth of crystals. Through the joint action of molecular recognition and self-assembly processes, new crystals with adjustable structures and specific physical and chemical properties are obtained. It is feasible to use the theory of crystal engineering to design dye eutectics, and use the principles of crystal engineering to connect organic dye components with other co-crystal precursors through hydrogen bonds to form new crystals. Organic dye components in crystalline form have traditionally been limited by their weak fluorescence and poor thermal stability. In terms of intellectual property rights, the organic dye components themselves have high application value, among which the structure and composition are the most important components. The Cambridge Structural Database (CSD) is the main source of microscopic information on the structure of matter for molecular design and materials design.

Fluorescence is an important property of matter and plays a vital role in many technical fields, such as fluorescent tumor markers and OLEDs. In some dyes, due to their structural characteristics and the characteristics of the functional groups contained, these dyes have certain fluorescent properties, which also makes these dyes have more uses. However, for solid-state dyes, in the case of close packing, exciton coupling will occur between dye molecules to generate new excitonic states, which will lead to the quenching of the fluorescence properties of the dyes.

Therefore, how to maintain or enhance the fluorescent properties of solid-state dyes is an urgent problem to be solved by those skilled in the art.

Contents of the invention

In view of this, the object of the present invention is to provide a 4,4'-azodibenzoic acid ethylenediamine dye co-crystal and a preparation method thereof, so as to solve the deficiencies in the prior art.

In order to achieve the above object, the present invention adopts the following technical solutions:

A 4,4′-azodibenzoic acid ethylenediamine dye eutectic, the molecular formula is C ₃₀ H ₂₄ N ₆ O ₈ , and the structural formula is

Furthermore, the above-mentioned 4,4'-azodibenzoic acid ethylenediamine dye eutectic is prepared by reacting 4,4'-azodibenzoic acid dye as an organic dye component and ethylenediamine as a precursor;

Among them, the molecular formula of 4,4′-azobisbenzoic acid is C ₁₄ H ₁₀ N ₂ O ₄ , and the structural formula is shown in a, which is

The molecular formula of ethylenediamine is C ₂ H ₈ N ₂ , and the structural formula is shown in b, which is

The beneficial effect of adopting the above-mentioned further technical scheme is that the present invention has significantly improved thermal stability compared with the dye itself by forming a co-crystal of the azo compound 4,4'-azobisbenzoic acid and ethylenediamine molecules . Moreover, it forms a co-crystal with ethylenediamine molecules, which enhances the transfer of electrons between dye molecules, making the fluorescence intensity of the co-crystal increase by nearly 5 times compared with the dye itself, which greatly solves the problem of poor thermal stability and fluorescence intensity of the original dye. weak problem.

Furthermore, the crystal structure of the above-mentioned 4,4'-azobisbenzoic acid ethylenediamine dye co-crystal is: one ethylenediamine molecule and two 4,4'-azobisbenzoic acid molecules are bound together by hydrogen bonds , forming the basic structural unit.

Further, in the above-mentioned 4,4'-azobisic acid ethylenediamine dye eutectic, an N atom (N1) on the amino group in an ethylenediamine molecule acts as a hydrogen bond donor, and two 4,4 The O atoms (O2 and O2 ⁱ ) on the carboxylic acid in the '-azodibenzoic acid molecule act as hydrogen bond acceptors to form two hydrogen bonds.

Furthermore, the space group of the above-mentioned 4,4'-azodibenzoic acid ethylenediamine dye eutectic is monoclinic, and the unit cell parameters are: axial length a=26.894-27.294, b=4.495-4.895, c=11.836 ～12.236; axis angle α=90.00, β=92.904～93.304, γ=90.00.

Further, the characteristic peaks of the XRD spectrum of the above-mentioned 4,4′-ethylenediamine azodibenzoic acid dye cocrystal appear at 5.96°-6.36°, 9.54°-9.94°, 10.34°-10.74°, 13.68°-14.08°, 15.85°～16.25°, 18.76°～19.16°, 22.37°～22.77°, 26.39°～26.79, 28.52°～28.92°. More specifically, they are 6.16°, 9.74°, 10.54°, 13.88°, 16.05°, 18.96°, 22.57°, 26.59°, 28.72°.

Further, the thermogravimetric curve of the above-mentioned 4,4'-azodiamine diamine dye eutectic under air atmosphere test conditions is as follows: at 152-248°C, the weight loss starts at 18%-19%, and then at 385-542°C Completely break down.

A kind of preparation method (solvent room temperature volatilization method) of above-mentioned 4,4'-azodibenzoic acid ethylenediamine dye eutectic, specifically comprises the following steps:

(1) Put 4,4'-azobisbenzoic acid, ethylenediamine and solvent together into a reaction vessel, place it on a stirrer under airtight conditions to stir, fully react, and obtain a red clear liquid;

(2) Seal the mouth of the reaction vessel with tinfoil, pierce several small holes in the tinfoil with a needle, let it stand for volatilization, and wait until the reaction vessel begins to precipitate red transparent blocky crystals to obtain 4,4′-azobis Ethylenediamine benzoate dye co-crystal.

Further, in the above step (1), the molar volume ratio of 4,4'-azobisbenzoic acid, ethylenediamine and solvent is (0.12～0.14)mmol:(0.16～0.18)mmol:(8～10)mL ; The solvent is prepared by mixing ethanol, methanol and water with a volume ratio of 7:2:1; the stirring time is 1 to 3 hours.

The beneficial effect of adopting the above-mentioned further technical solution is that the boiling point of the solvent selected in the present invention is relatively low, so crystals are precipitated during the process of solvent volatilization.

Further, in the above step (2), the time for standing to volatilize is 7 to 10 days.

Via the above-mentioned technical scheme, it can be seen that compared with the prior art, the beneficial effects of the present invention are as follows:

The solid-state quinoline azo fluorescent dye eutectic with a novel structure of the present invention has significantly improved thermal stability compared with the dye itself, and its fluorescence intensity has increased by 5 times compared with the dye itself, which greatly solves the problem of the original dye There are problems with stability and fluorescence intensity.

Description of drawings

Fig. 1 is the structural unit schematic diagram of the 4,4'-azodibenzoic acid ethylenediamine dye eutectic that embodiment 1 makes;

Fig. 2 is the XRD spectrogram and the simulated XRD spectrogram of the 4,4'-azodibenzoic acid ethylenediamine dye eutectic obtained in Example 1;

Fig. 3 is the thermal gravimetric spectrum of the 4,4'-azodibenzoic acid ethylenediamine dye co-crystal prepared in Example 1.

Detailed ways

The following clearly and completely describes the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In the following examples, the reaction container is a transparent glass vial, imported from abroad, with a capacity of 20 mL, which has strong airtightness and can maintain good airtightness at temperatures below 120°C.

Example 1

The preparation method of 4,4'-ethylenediamine azodibenzoic acid dye cocrystal specifically comprises the following steps:

(1) First use a 10mL pipette to measure 7mL of ethanol, 2mL of methanol and 1mL of water in a 20mL transparent glass vial and mix to obtain a solvent; then add 0.13mmol (35.00mg) accurately weighed with an analytical balance4,4 '-Azodibenzoic acid and 0.17mmol (10.20mg) ethylenediamine were placed on a stirrer under airtight conditions and stirred for 2h to fully react to obtain a red clear liquid;

(2) Take out the stirring bar, seal the mouth of the reaction vessel with tinfoil, pierce several small holes on the tinfoil with a needle, let it stand for 9 days to evaporate, and wait for red transparent massive crystals to precipitate in the reaction vessel to obtain 4, 4'-Azodibenzoic acid ethylenediamine dye co-crystal.

Example 2

The preparation method of 4,4'-ethylenediamine azodibenzoic acid dye cocrystal specifically comprises the following steps:

(1) First use a 10mL pipette to measure 7mL of ethanol, 2mL of methanol and 1mL of water in a 20mL transparent glass vial and mix to obtain a solvent; then add 0.12mmol (32.00mg) accurately weighed with an analytical balance4,4 '-Azodibenzoic acid and 0.16mmol (9.60mg) of ethylenediamine were placed on a stirrer under airtight conditions and stirred for 1h to fully react to obtain a red clear liquid;

(2) Take out the stirring bar, seal the mouth of the reaction vessel with tinfoil, pierce several small holes on the tinfoil with a needle, let it stand for volatilization for 7 days, and wait for the reaction vessel to start to precipitate red transparent massive crystals, to obtain 4, 4'-Azodibenzoic acid ethylenediamine dye co-crystal.

Example 3

The preparation method of 4,4'-ethylenediamine azodibenzoic acid dye cocrystal specifically comprises the following steps:

(1) First use a 10mL pipette to measure 7mL of ethanol, 2mL of methanol and 1mL of water in a 20mL transparent glass vial and mix to obtain a solvent; then add 0.14mmol (38.00mg) accurately weighed with an analytical balance4,4 '-Azodibenzoic acid and 0.18mmol (10.80mg) ethylenediamine were placed on a stirrer under airtight conditions and stirred for 3h to fully react to obtain a red clear liquid;

(2) Take out the stirring bar, seal the mouth of the reaction vessel with tinfoil, pierce several small holes on the tinfoil with a needle, let it stand for volatilization for 10 days, and start to precipitate red transparent block crystals in the reaction vessel to obtain 4, 4'-Azodibenzoic acid ethylenediamine dye co-crystal.

Performance Testing

1. Take the 4,4′-azodibenzoic acid ethylenediamine dye cocrystal prepared in Example 1, and use Bruker Apex IICCD X-ray single crystal diffractometer (Bruker SMART-APEX CCD Diffractometer) to determine its structural units. The result is shown in Figure 1.

It can be known from Figure 1 that one molecule of ethylenediamine and two molecules of 4,4'-azodibenzoic acid are bound together by hydrogen bonds to form a basic structural unit. Among them, an N atom (N1) on the amino group in an ethylenediamine molecule is used as a hydrogen bond donor, and an O atom (O2 and O2 ⁱ ) acts as a hydrogen bond acceptor to form two hydrogen bonds.

The space group of the eutectic is monoclinic, and its unit cell parameters are as follows: axial length a=26.894～27.294, b=4.495～4.895, c=11.836～12.236; axial angle α=90.00, β=92.904～93.304, Gamma = 90.00.

2. Take the 4,4'-azodibenzoic acid ethylenediamine dye cocrystal obtained in Example 1, use X-RayDIFFRACTOMETER (produced by Shimadzu Corporation, model XRD-6000), Cu-Kα The tube voltage was 40kV, the tube current was 30mA, and the scanning speed was 8°/min, and its XRD spectrum was measured. And according to the crystal structure data, its XRD spectrum was simulated by MaterialsStudio software. The result is shown in Figure 2.

As can be seen from Fig. 2, as can be seen from the X-ray diffraction spectrum peak (curve a) of this eutectic, at 5.96°～6.36°, 9.54°～9.94°, 10.34°～10.74°, 13.68°～14.08°, A series of characteristic peaks appear at 15.85°～16.25°, 18.76°～19.16°, 22.37°～22.77°, 26.39°～26.79, 28.52°～28.92°, more specifically 6.16°, 9.74°, 10.54°, 13.88°, 16.05 °, 18.96°, 22.57°, 26.59°, 28.72°. Moreover, it can be seen through comparison that these characteristic peaks are consistent with the simulated X-ray diffraction peaks (curve b).

3. Get the 4,4'-azodibenzoic acid ethylenediamine dye cocrystal obtained in Example 1, use the thermogravimetric (TGA) and The differential thermal analyzer (DTA) adopts an air atmosphere, and the heating rate is 10°C/min, and the thermogravimetric spectrum is measured. The result is shown in Figure 3.

It can be seen from Fig. 3 that the thermogravimetric curve of the eutectic under air atmosphere test conditions is: 18%-19% weight loss at 152-248°C, and then complete decomposition at 385-542°C.

4. Take the 4,4'-azobisbenzoic acid and the prepared 4,4'-azobisbenzoic acid ethylenediamine dye eutectic in Example 1, respectively, and measure their fluorescence intensity respectively.

It was found that 4,4'-azodibenzoic acid had a PeakA [fluorescence intensity of 56 (au)] at λ _EX/EM = 280/322nm, and when it formed 4,4'-azodiphenyl PeakA [fluorescence intensity of 286 (au)] at λ _EX/EM = 312/334 nm after co-crystallization of ethylenediamine formic acid dye.

The above test shows that the solid-state quinoline azo fluorescent dye eutectic with novel structure of the present invention has significantly improved thermal stability relative to the dye itself, and its fluorescence intensity has increased by 5 times relative to the dye itself, which greatly solves the problem. The problems existing in the stability and fluorescence intensity of the original dyes were overcome.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. A4, 4' -azo dibenzoic acid ethylenediamine dye eutectic is characterized in that the molecular formula is C ₃₀ H ₂₄ N ₆ O ₈ The structural formula is

2. The co-crystal of 4,4 '-azobisbenzoic acid ethylenediamine dye according to claim 1, wherein the dye 4,4' -azobisbenzoic acid is used as an organic dye component, ethylenediamine is used as a precursor, and the co-crystal is prepared by reaction;

the molecular formula of the 4,4' -azo dibenzoic acid is C ₁₄ H ₁₀ N ₂ O ₄ The structural formula is

The molecular formula of the ethylenediamine is C ₂ H ₈ N ₂ The structural formula is

3. The co-crystal of 4,4' -azobisbenzoic acid ethylenediamine dye according to claim 2, wherein the crystal structure is: one ethylenediamine molecule and two 4,4' -azobisbenzoic acid molecules are combined together through hydrogen bonds to form a basic structural unit.

4. The co-crystal of 4,4 '-azobisbenzoic acid ethylenediamine dye according to claim 3, wherein one N atom on an amino group in one ethylenediamine molecule is used as a hydrogen bond donor, and an O atom on a carboxylic acid in two 4,4' -azobisbenzoic acid molecules is used as a hydrogen bond acceptor to form two hydrogen bonds.

5. The co-crystal of ethylenediamine 4,4' -azobisbenzoate dye according to claim 1 wherein the space group is monoclinic, the unit cell parameters are: the axial length a= 26.894-27.294, b= 4.495-4.895 and c= 11.836-12.236; the shaft angle α=90.00, β= 92.904 to 93.304, γ=90.00.

6. The co-crystal of 4,4' -azobisbenzoic acid ethylenediamine dye according to claim 1 wherein the XRD spectrum characteristic peaks appear at 5.96 ° to 6.36 °,9.54 ° to 9.94 °,10.34 ° to 10.74 °,13.68 ° to 14.08 °,15.85 ° to 16.25 °,18.76 ° to 19.16 °,22.37 ° to 22.77 °,26.39 ° to 26.79, 28.52 ° to 28.92 °.

7. The co-crystal of ethylenediamine 4,4' -azobisbenzoate dye according to claim 1 wherein the thermogravimetric curve under air atmosphere test conditions is: the weight loss is 18 to 19 percent at the temperature of 152 to 248 ℃, and then the mixture is completely decomposed at the temperature of 385 to 542 ℃.

8. A method for preparing the co-crystal of the 4,4' -azobisbenzoic acid ethylenediamine dye according to claim 1, comprising the following steps:

(1) Placing 4,4' -azobisbenzoic acid, ethylenediamine and a solvent into a reaction vessel, placing the reaction vessel on a stirrer under a closed condition, stirring, and fully reacting to obtain a red clear liquid;

(2) Sealing the mouth of the reaction container by using tinfoil, punching a plurality of small holes on the tinfoil by using a needle, standing for volatilization, and obtaining the 4,4' -azo-bis-benzoic acid ethylenediamine dye eutectic when red transparent blocky crystals begin to be separated out from the reaction container.

9. The method for preparing an ethylenediamine 4,4 '-azobisbenzoate dye co-crystal according to claim 8, wherein in the step (1), the molar volume ratio of the ethylenediamine to the 4,4' -azobisbenzoate dye is (0.12-0.14) mmol (0.16-0.18) mmol (8-10) mL; the solvent is prepared by mixing ethanol, methanol and water in a volume ratio of 7:2:1; the stirring time is 1-3 h.

10. The method for preparing an ethylenediamine 4,4' -azobisbenzoate dye co-crystal according to claim 8, wherein in the step (2), the standing volatilization time is 7-10 days.