Bis-cuprous complex as well as preparation method and application thereof

Abstract

The invention discloses a double-cuprous complex and a preparation method and application thereof.The double-cuprous complex is specifically a binuclear cuprous complex which is formed by two cuprous ions, four N atoms of bitzH2 and P atoms on two POP and has two twisted tetrahedral configurations, solid powder of the complex emits blue light, and the double-cuprous complex can be used for preparing blue light. After mechanical grinding, blue fluorescence is converted into green fluorescence, and after a ground solid sample is fumigated by dichloromethane steam, blue light is recovered, so that the compound has a reversible force-induced color-changing property and also has high optical contrast; the characteristics of wide color gamut change range and high color vividness are beneficial to the preparation of high-contrast force sensing materials, and have huge application potential in the fields of force sensors, memories, anti-counterfeiting marks and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of mechanochromic materials, and in particular relates to a di-cuprous complex and a preparation method and application thereof. Background Art

[0002] Mechanochromic materials have attracted widespread research interest from scientists due to their potential application value in the fields of mechanical sensors, anti-counterfeiting, and information storage. Mechanochromic materials have the ability to change their visible color in response to mechanical force. Under the action of external mechanical force, the optical properties of smart materials with mechanochromic properties will change. To date, many pure organic compounds with mechanochromic properties have been reported. In comparison, there are fewer reports on metal complexes with mechanochromic properties. The coordination bonds of metal complexes are more sensitive to external forces. Slight mechanical stress can trigger changes in the coordination environment (such as bond length, bond angle, or coordination number), thereby triggering a faster color response than pure organic compounds.

[0003] In the study of stimulus-responsive luminescent materials, noble metal complexes (such as platinum, iridium, ruthenium, etc.) have long dominated due to their excellent photophysical properties and stability. These complexes usually exhibit efficient photoluminescence and electroluminescence properties and are widely used in fields such as organic light-emitting diodes (OLEDs), chemical sensors, and bioimaging. For example, patents CN111187286A and CN118598890A report two gold complexes with mechanochromic properties. However, the high cost and scarcity of noble metals limit their large-scale application. The first transition metals (such as copper, zinc, nickel, etc.) have gradually become a research hotspot due to their abundant reserves, low prices, and controllable optical properties. Therefore, how to prepare the first transition metals into mechanochromic materials is a problem that scientists in this field need to solve. Summary of the Invention

[0004] In order to overcome the problems existing in the above-mentioned prior art, one object of the present invention is to provide a di-cuprous complex. A second object of the present invention is to provide a method for preparing the di-cuprous complex. A third object of the present invention is to provide applications of the di-cuprous complex.

[0005] Cuprous (Cu(I)) complexes have unique d 10The electronic configuration and flexible coordination geometry show significant advantages in the field of stimulus-responsive luminescence. Cuprous complexes usually have lower energy excited states and higher luminescence efficiency, and their luminescence behavior is highly sensitive to external stimuli (such as light, heat, pressure, solvent polarity, etc.). This stimulus-responsive characteristic gives cuprous complexes broad application prospects in the fields of smart luminescent materials, sensors, and information storage. In addition, cuprous complexes can achieve precise control of luminescence color and intensity through ligand design and coordination environment regulation, further expanding their application potential in multifunctional luminescent materials. Therefore, as an efficient, economical and environmentally friendly luminescent material, cuprous complexes have important research significance and application value in the field of stimulus-responsive luminescence. The present invention proposes a triazole binuclear cuprous complex, which has reversible mechanochromic properties and can be used in fields such as force sensors, memories, and anti-counterfeiting labels.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] The first aspect of the present invention provides a bis-cuprous complex, the structural formula of the cuprous complex is shown in Formula A:

[0008]

[0009] Preferably, the cuprous complex is a single crystal material.

[0010] More preferably, the cuprous complex is a white block crystal.

[0011] Preferably, the bis-cuprous complex has two distorted tetrahedral configurations.

[0012] The second aspect of the present invention provides a method for preparing the di-cuprous complex described in the first aspect, comprising the following steps:

[0013] S1, bis(2-diphenylphosphinophenyl)ether and [Cu(MeCN)4](ClO4) are reacted to carry out reaction 1, and then 5,5'-bis(trifluoromethyl)-2H,2'H-3,3'-bi(1,2,4-triazole) is added to the reaction system to carry out reaction 2;

[0014] S2. The solid product obtained in step S1 reaction 2 is dissolved in a solvent again, and the di-cuprous complex is obtained by a solvent diffusion method.

[0015] Preferably, the molar ratio of the bis(2-diphenylphosphinophenyl)ether to [Cu(MeCN)4](ClO4) is (0.65-1.5):1.

[0016] More preferably, the molar ratio of the bis(2-diphenylphosphinophenyl)ether to [Cu(MeCN)4](ClO4) is (0.9-1.1):1.

[0017] Preferably, the molar ratio of the 5,5'-bis(trifluoromethyl)-2H,2'H-3,3'-bi(1,2,4-triazole) to [Cu(MeCN)4](ClO4) is (0.65-1.5):1.

[0018] Preferably, the molar ratio of the 5,5'-bis(trifluoromethyl)-2H,2'H-3,3'-bi(1,2,4-triazole) to [Cu(MeCN)4](ClO4) is (0.9-1.1):1.

[0019] Preferably, the reaction temperature of the reaction 1 is 15-40°C.

[0020] More preferably, the reaction temperature of the reaction 1 is 20-30°C.

[0021] Preferably, the reaction time of reaction 1 is 20 to 60 minutes.

[0022] More preferably, the reaction time of the reaction 1 is 20 to 40 minutes.

[0023] Preferably, the reaction temperature of the reaction 2 is 15-40°C.

[0024] More preferably, the reaction temperature of the reaction 2 is 20-30°C.

[0025] Preferably, the reaction time of reaction 2 is 90 to 150 minutes.

[0026] More preferably, the reaction time of the reaction 2 is 100 to 140 minutes.

[0027] Preferably, the reaction 1 and the reaction 2 are carried out under a protective atmosphere.

[0028] More preferably, the protective atmosphere is a nitrogen atmosphere.

[0029] Preferably, the reaction 1 and the reaction 2 are carried out in a solvent.

[0030] More preferably, the solvent includes at least one of dichloromethane, chloroform, acetone, and tetrahydrofuran.

[0031] Preferably, the solvent in step S2 is a mixed solution of dichloromethane and acetone.

[0032] Preferably, the solvent diffusion method uses diethyl ether or n-hexane as the diffusion solvent.

[0033] Preferably, the solvent diffusion method is performed at room temperature, specifically at room temperature for 3 to 7 days.

[0034] Preferably, the method for separating the solid product obtained by the S1 reaction 2 comprises: spinning the solution after the reaction 2 to dryness to obtain the solid product obtained by the S1 reaction 2.

[0035] Preferably, the preparation method of [Cu(MeCN)4](ClO4) comprises the following steps: dissolving basic copper carbonate in perchloric acid to obtain a basic copper carbonate solution, mixing the basic copper carbonate solution with an acetonitrile solution containing copper powder, and reacting to obtain the [Cu(MeCN)4](ClO4).

[0036] The second aspect of the present invention provides the use of the bis-cuprous complex described in the first aspect in a mechanochromic luminescent material.

[0037] Preferably, the bis-cuprous complex is used in the fields of mechanical sensors, anti-counterfeiting and information storage.

[0038] The beneficial effects of the present invention are:

[0039] 1. The present invention proposes a di-cuprous complex, specifically a binuclear cuprous complex with two distorted tetrahedral configurations formed by two cuprous ions, four N atoms of a bitzH2, and two P atoms on POP. The solid powder of the complex exhibits blue luminescence. After mechanical grinding, the blue fluorescence turns to green fluorescence. After fumigating the ground solid sample with dichloromethane vapor, the blue fluorescence returns to blue. Therefore, the compound has reversible mechanochromic properties and high optical contrast. Its wide color gamut and high color vividness are conducive to the preparation of high-contrast force sensing materials and have great application potential in the fields of force sensors, memory devices, and anti-counterfeiting labels.

[0040] 2. The present invention also proposes a method for preparing the above-mentioned di-cuprous complex. The material synthesis route provided by the present invention is simple, easy to operate, low in cost, high in yield, and easy to achieve industrial production. The obtained di-nuclear cuprous complex of triazole has excellent luminescence properties and exhibits stimulus-responsive luminescence properties of grinding color change and steam color change. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a single crystal structure diagram of the dinuclear cuprous complex of triazole in Example 1;

[0042] Figure 2 This is the H NMR spectrum of the dinuclear cuprous complex of triazole in Example 1;

[0043] Figure 3 This is the NMR phosphine spectrum of the dinuclear cuprous complex of triazole in Example 1;

[0044] Figure 4This is the infrared spectrum of the dinuclear cuprous complex of triazole in Example 1;

[0045] Figure 5 This is a diagram showing the color change of the triazole binuclear cuprous complex of Example 1 after grinding and fumigation;

[0046] Figure 6 The fluorescence spectra of the dinuclear cuprous triazole complex of Example 1, the complex after grinding, and the complex after fumigation;

[0047] Figure 7 1 and 2 are powder diffraction patterns of the dinuclear cuprous triazole complex of Example 1, the complex after grinding, and the complex after fumigation. DETAILED DESCRIPTION

[0048] The present invention is further described in detail below through specific examples. Unless otherwise specified, the raw materials used in the following examples can be obtained from conventional commercial sources or prepared and isolated by simple synthesis; unless otherwise specified, the processes used are conventional processes in the art.

[0049] Example 1

[0050] This embodiment provides a triazole binuclear cuprous complex, the structural formula of which is shown in Formula A:

[0051]

[0052] The preparation method of the triazole binuclear cuprous complex is as follows:

[0053] S1. The preparation of [Cu(MeCN)4](ClO4) was based on the literature [Mukherjee J, Mukherjee R. Reaction with dioxygen of a Cu(I) complex of 1-benzyl-[3-(2'-pyridyl)]pyrazole triggers ethyl acetate hydrolysis: acetato- / pyrazolato-, dihydroxo- and diacetato-bridgedCu(II) complexes[J]]. Dalton transactions: An international journal of inorganic chemistry, 2006, 0(13)]. The relevant steps are as follows: 2 g of basic copper carbonate was placed in a beaker, and 1.7 mL of perchloric acid was slowly added dropwise while stirring until the basic copper carbonate was completely dissolved; then, the dissolved solution was transferred to 150 mL of acetonitrile solution containing 15 g of copper powder and stirred for 30 minutes. The solvent was then drained to obtain white [Cu(MeCN)4](ClO4).

[0054] The preparation of S2, 5,5'-bis(trifluoromethyl)-2H,2'H-3,3'-bi(1,2,4-triazole) was prepared according to the literature [Ru(II)sensitizers bearing dianionic biazolate ancillaries:ligand synergy forhigh performance dye sensitized solar cells]. The relevant steps are as follows: oxalyl dihydrazide (1.00 g, 8.5 mmol) and trifluoroacetamidine (2.38 g, 21.2 mmol) were weighed and placed in a reaction flask, and 100 ml of ethanol was added as the reaction solvent. After heating to reflux for 24 hours, the solid was collected by filtration and washed with an appropriate amount of water. After vacuum drying, the intermediate product was transferred to a single-necked flask and heated to 280°C for 2 hours of dehydration reaction. The final crude product was purified by sublimation (180° C., 10 −1 torr) to obtain a white solid product, namely 5,5′-bis(trifluoromethyl)-2H,2′H-3,3′-bi(1,2,4-triazole).

[0055] S3. Under nitrogen, bis(2-diphenylphosphinophenyl) ether and [Cu(MeCN)4](ClO4) were stirred in dichloromethane at room temperature for 30 minutes; the masses of bis(2-diphenylphosphinophenyl) ether (POP) and [Cu(MeCN)4](ClO4)(bitzH2) were 0.054 and 0.033 g, respectively, with a molar ratio of 1:1, and the volume of dichloromethane was 3 mL;

[0056] S4. Continue to add 0.028 g of 5,5'-bis(trifluoromethyl)-2H,2'H-3,3'-bi(1,2,4-triazole), bis(2-diphenylphosphinophenyl) ether and 5,5'-bis(trifluoromethyl)-2H,2'H-3,3'-bi(1,2,4-triazole) and [Cu(MeCN)4](ClO4) in a molar ratio of (1:1:1), and continue stirring at room temperature for 2 hours.

[0057] S5. The reaction solution was spin-dried, redissolved with a dichloromethane:acetone solution with a volume ratio of 10:1 (the volume of the solution was 4 mL), transferred to four test tubes, and covered with 12 mL of n-hexane. After 5 days, a triazole binuclear cuprous complex was obtained. The chemical formula of the obtained triazole cuprous complex is [{Cu2(bitzH2)}(μ-POP)2](ClO4)2.

[0058] Material characterization

[0059] Figures 1-4 They are the single crystal structure diagram, H NMR spectrum, phosphine NMR spectrum and infrared spectrum of the dinuclear cuprous complex of triazole of Example 1. Figure 1 As shown, crystal structure analysis revealed that the two cuprous ions formed a dinuclear cuprous complex with two distorted tetrahedral configurations through the four N atoms of a bitzH2 and the P atoms on two POPs. 1 H NMR) analysis showed ( Figure 2 ), the integrated area of ​​each characteristic peak is highly consistent with the results of single crystal X-ray diffraction analysis, which provides direct evidence for the successful synthesis of the triazole binuclear cuprous complex. It is worth noting that 31 PNMR spectrum ( Figure 3 ) presents only a single sharp peak at the corresponding chemical shift, indicating that the phosphorus atoms in the four phosphine ligands are in completely identical coordination environments, which further confirms the symmetrical coordination mode observed in the crystal structure. Infrared spectroscopy characterization results ( Figure 4 ) Display: Located at 1100cm -1 The strong absorption peak at 1600 cm is attributed to the characteristic vibration of perchlorate anion; -1 The absorption band at 3200 cm corresponds to the in-plane bending vibration of the NH bond, while the absorption band at 3200 cm -1 The broad peak at is attributed to the stretching vibration of the NH bond. The systematic appearance of these characteristic peaks fully reveals the structural characteristics of the triazole ligand in the complex. The mutual support of the above multi-spectral characterization data fully confirms the precise structure of the target complex and its successful synthesis at the molecular level.

[0060] Mechanochromic experimental characterization

[0061] Figure 5 This is the color change diagram of the triazole binuclear cuprous complex of Example 1 after grinding and fumigation. Figure 6 The fluorescence spectra of the dinuclear cuprous triazole complex of Example 1, the ground complex, and the fumigated complex at an excitation wavelength of 365 nm are shown. After grinding the crystals for 0.5 h, the sample color changed from blue to green, and the maximum emission peak of the fluorescence spectrum also underwent a significant red shift, from 460 nm to 505 nm. After exposing the ground sample to dichloromethane vapor for 10 minutes, the color returned to blue, and the maximum emission peak of the fluorescence spectrum also returned to 505 nm. This demonstrates that this material exhibits both color reversibility upon grinding and high optical contrast. Its wide color gamut and high color vividness are advantageous for the preparation of high-contrast force sensing materials.

[0062] Figure 7 This is the powder diffraction pattern of the complex during the milling and fumigation process. The powder diffraction pattern of the initial sample is consistent with that of the single crystal simulation, indicating the high phase purity of the complex. However, the powder diffraction peaks of the milled sample differ from those of the initial sample, indicating that milling disrupts the molecular crystal structure. After fumigation with dichloromethane vapor, the diffraction peaks return to essentially the same peaks as the initial sample, demonstrating that this stimulus-responsive luminescence process is fully reversible.

[0063] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered as equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. A cuprous complex, characterized in that The structural formula of the cuprous complex is shown in Formula A:

2. The cuprous complex according to claim 1, wherein The double cuprous complex is a single crystal material.

3. The method for preparing the double cuprous complex according to claim 1 or 2, wherein: The steps include: S1, bis(2-diphenylphosphinophenyl)ether and [Cu(MeCN)4](ClO4) are reacted to carry out reaction 1, and then 5,5'-bis(trifluoromethyl)-2H,2'H-3,3'-bi(1,2,4-triazole) is added to the reaction system to carry out reaction 2; S2. The solid product obtained by the reaction of S1 is dissolved in a solvent again, and the di-cuprous complex is obtained by a solvent diffusion method.

4. The method for preparing a double cuprous complex according to claim 3, wherein The molar ratio of the bis(2-diphenylphosphinophenyl)ether and [Cu(MeCN)4](ClO4) is (0.65-1.5):1; And / or, the molar ratio of the 5,5'-bis(trifluoromethyl)-2H,2'H-3,3'-bi(1,2,4-triazole) to [Cu(MeCN)4](ClO4) is (0.65-1.5):

1.

5. The method for preparing a double cuprous complex according to claim 3, wherein The reaction temperature of the reaction 1 is 15 to 40°C; And / or, the reaction time of the reaction 1 is 20 to 60 minutes.

6. The method for preparing a double cuprous complex according to claim 3, wherein: The reaction temperature of the reaction 2 is 15 to 40°C; And / or, the reaction time of the reaction 2 is 90 to 150 minutes.

7. The method for preparing a double cuprous complex according to claim 3, wherein: The solvent diffusion method uses ether or n-hexane as the diffusion solvent.

8. The method for preparing a double cuprous complex according to claim 3, wherein: The preparation method of [Cu(MeCN)4](ClO4) comprises the following steps: dissolving basic copper carbonate in perchloric acid to obtain a basic copper carbonate solution, mixing the basic copper carbonate solution with an acetonitrile solution containing copper powder, and reacting to obtain the [Cu(MeCN)4](ClO4).

9. Use of the double cuprous complex according to claim 1 or 2 in a mechanochromic luminescent material.

10. The use according to claim 9, characterized in that The bis-cuprous complex is used in the fields of mechanical sensors, anti-counterfeiting and information storage.

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