Multifunctional compounds based on tris(quinoline-5-methoxy-diachydrazide)benzene, their synthesis and applications

Abstract

This invention provides a multifunctional compound, TQ5, based on tris(quinoline-5-methoxy-diachydrazide)benzene, for highly sensitive detection of phosgene and triphosgene and efficient separation of heavy metal ions. The concentration is 1×10⁻⁶. ‑5 When triphosgene solution was added to a TQ5 1,4-dioxane solution of M, the fluorescence of the solution at 365 nm changed from colorless to bright green. However, the fluorescence of solutions containing common volatile toxic gases did not change significantly upon addition. The detection limit of triphosgene reached 4.70 × 10⁻⁶. ‑8 M. Similarly, the same mechanism can be used for the detection and identification of highly toxic phosgene. Furthermore, this invention is based on TQ5 compound phosgene fluorescent colorimetric material for convenient, rapid, and highly sensitive detection of triphosgene and phosgene in real-world environments. Finally, TQ5 dry gel powder can be applied to the efficient detection and adsorption separation of heavy metal ions in water, including Cd. 2+ Hg 2+ Ag + The adsorption rates reached 80.85%, 91.64%, and 88.62%, respectively. This study provides a new method for developing multifunctional supramolecular smart materials for multi-substrate detection and separation, which has certain application prospects in the fields of food and environmental safety detection and control.

Description

Technical Field

[0001] This invention relates to a multifunctional compound based on tris(quinoline-5-methoxy-diachydrazido)benzene and its synthesis method; this invention also relates to the application of this multifunctional compound TQ5 in the fluorescence detection of phosgene / triphosgene and in the efficient adsorption and separation of heavy metal ions, belonging to the fields of chemical synthesis, molecular detection and ion adsorption. Background Technology

[0002] Triphosgene (C3Cl6O3, BTC), as a safer alternative to highly toxic phosgene (COCl2), is widely used in pharmaceutical, dye, and chemical research fields due to its solid-state properties. However, in industry, numerous phosgene poisoning incidents caused by leaks have highlighted the continued safety concerns surrounding the storage and application of triphosgene. Therefore, developing more effective detection methods for qualitative identification of phosgene and triphosgene is crucial for safety in industrial production. Currently, its detection still faces some challenges. For example, most known triphosgene probes have detection lines of up to 10... -6 The concentration of M is crucial; therefore, further research is needed for ultrasensitive detection at the micromolar level or even smaller. While traditional instrument detection can achieve ultrasensitive detection, it suffers from problems such as lack of portability, long response time, and high instrument cost. Therefore, it is both necessary and feasible to design and synthesize ultrasensitive, instantaneous, highly selective, portable, and low-cost phosgene and triphosgene detection methods by utilizing the properties of functional supramolecular molecules.

[0003] Toxic metal ions refer to toxic metallic elements existing in water or other environmental media in ionic form. These ions migrate into plants through soil and water, affecting plant growth and development, threatening ecological balance, and causing a series of adverse effects on human health, such as kidney and liver damage or other diseases. Therefore, highly sensitive real-time monitoring of heavy metal concentrations in the environment and analysis and purification using instrumental and chemical methods to reduce their harm to human health and ecosystems are important issues facing modern society.

[0004] Based on this, the present invention designs and synthesizes a three-legged supramolecular multifunctional compound, TQ5, formed by introducing an acetylhydrazine-modified oxyquinoline fluorescent group. Utilizing the nitrogen atom in the quinoline group as a reaction site, it reacts with the acyl chloride structures of phosgene and triphosgene. This reaction signal is amplified via fluorescence. Therefore, its solution can achieve ultrasensitive identification and detection of highly toxic phosgene and triphosgene. Simultaneously, due to the presence of numerous supramolecular forces such as hydrogen bonding and synergistic effects, as well as the loose and porous structure of the dry gel powder, adsorption and separation of heavy metal ions are achieved. Summary of the Invention

[0005] The purpose of this invention is to provide a multifunctional compound, TQ5, that can detect phosgene / triphosgene with fluorescence and efficiently adsorb heavy metals;

[0006] Another object of the present invention is to provide a method for synthesizing the above-mentioned multifunctional compound TQ5;

[0007] Another objective of this invention is to provide the application of the multifunctional compound TQ5 in the fluorescence detection of phosgene / triphosgene and the efficient adsorption of heavy metals.

[0008] I. TQ5, a multifunctional compound based on tris(quinoline-5-methoxy-diazidyl)benzene, and its synthesis

[0009] The molecular formula of the multifunctional compound based on tris(quinoline-5-methoxy-diachydrazido)benzene in this invention is: C 42 H 33 N9O9, designated as TQ5, has the following structural formula:

[0010] .

[0011] Synthesis of the multifunctional compound TQ5: A DCM solution of 1,3,5-pyromellitic trimethylbenzene chloride was added dropwise to a DCM solution of 2-(quinoline-5-oxy)acetylhydrazine. After stirring at room temperature for 20-25 hours, the mixture was washed, filtered, and purified by recrystallization with DMF and water. The purified compound was then dried under vacuum to obtain the multifunctional compound TQ5 based on tri(quinoline-5-methoxy-diacylhydrazine)benzene. The molar ratio of 1,3,5-pyromellitic trimethylbenzene chloride to 2-(quinoline-5-oxy)acetylhydrazine was 1:3 to 1:3.3.

[0012] The structural formula of 2-(quinoline-5-oxy)acetylhydrazine (Q5) is: .

[0013] II. Application of the multifunctional compound TQ5 in the detection of phosgene / triphosgene

[0014] 1. Fluorescence properties of the multifunctional compound TQ5

[0015] Studies on the fluorescence properties of the multifunctional compound TQ5 show that it possesses certain solubility (1×10⁻⁶) in 1,4-dioxane solution. -5 M), which is colorless fluorescent under a 365nm fluorescent lamp.

[0016] 2. The multifunctional compound TQ5 identifies phosgene / triphosgene.

[0017] Figure 3 A 1,4-dioxane solution (C) of the multifunctional compound TQ5 of the present invention. TQ5 =1×10 -5The fluorescence intensity change (λ) of 20-fold equivalent triphosgene in M) ex =420 nm). By Figure 3 It was found that the 1,4-dioxane solution of TQ5 exhibited a maximum emission peak at 384 nm under an excitation wavelength of 420 nm. After adding 20 equivalents of triphosgene solution, the fluorescence peak at 384 nm gradually decreased, and a new fluorescence peak appeared at 416 nm. Simultaneously, the fluorescence of the DMSO solution of TQ5 changed from colorless to bright green after the addition of triphosgene.

[0018] Figure 4 Methanol, ethanol, acetone, benzene, toluene, formaldehyde, acetaldehyde, dichloromethane, ammonia, hydrazine hydrate, phenol, diethyl ether, carbon disulfide, and DMSO solution of triphosgene were added to a 1,4-dioxane solution of TQ5, respectively. It can be seen that only the TQ5 solution of the sensor with added triphosgene solution showed fluorescence, indicating that the multifunctional compound TQ5 is selective for triphosgene.

[0019] Fluorescent titration experiments showed that the limit of detection for triphosgene fluorescence of the multifunctional compound TQ5 was 4.70 × 10⁻⁶. -8 M, (e.g.) Figure 5 , Figure 6 ).

[0020] 3. Analysis of the recognition mechanism of phosgene and triphosgene by the multifunctional compound TQ5

[0021] Figure 7 This is an NMR titration diagram of the multifunctional compound TQ5 of this invention and triphosgene recognition. In the diagram, a, b, c, d, e, f, and g correspond to the changes in the hydrogen proton signal peaks corresponding to the addition of 0, 0.5, 1, 1.5, 2, 3, and 4.5 times the equivalent of triphosgene, respectively. Figure 7 1 1H NMR titration results showed that the hydrogen atoms on the quinoline ring underwent a low-field shift when 0–4.5 equivalents of triphosgene were gradually added to the TQ5 solution, indicating that the reaction occurred only on the quinoline ring. Figure 9 The high-resolution mass spectrometry data shown indicates that in this reactive recognition, the triphosgene acyl chloride structure reacts with the nucleophilic N atom in the quinoline group of TQ5 to form an N-acylchloroquinoline structure as shown in Figure 8. This structure exhibits bright green fluorescence in a dilute solution of 1,4-dioxane, and the fluorescence of the sensor solution gradually increases with the addition of the reactant triphosgene. Figure 10 Before the reaction, TQ5 was observed to be dispersed in 1,4-dioxane as regular lumps in the scanning electron microscope image. However, after the addition of triphosgene, the product dispersion morphology showed a regular lumpy stacking state, which indirectly verified the occurrence of the reaction.

[0022] 4. Multifunctional compound TQ5: A practical detection device for phosgene and triphosgene.

[0023] Since the detection mechanism of triphosgene is also applicable to the detection of highly toxic phosgene, this invention, in order to achieve real-time fluorescence visualization of highly toxic phosgene, developed a TQ5-loaded fluorescent colorimetric material for the preliminary quantitative detection of triphosgene and the qualitative detection of gaseous phosgene. For example... Figure 11 The fluorescent colorimetric material shown can be used for the preliminary quantitative detection of triphosgene solutions, and it can produce an immediate fluorescence response when exposed to phosgene, emitting obvious bright green fluorescence.

[0024] 5. Adsorption rate of TQ5 gel powder for toxic metal ions in aqueous solution

[0025] A multifunctional compound, TQ5 (w%=1%) hydrogel, was prepared by ultrasonication. The hydrogel was then dried naturally to obtain TQ5 dry gel powder. Two mg of TQ5 dry gel powder was added to 5 ml (0.03 M) of a metal ion solution and ultrasonically dispersed for 0.5 hours. After centrifugation using a high-speed centrifuge, the supernatant was filtered through an organic phase membrane. This method enabled the adsorption and separation of heavy metal ions in water.

[0026] Figure 11 a) The response of the TQ5 smart phosgene fluorescent display material to phosgene under ultraviolet light (365nm); when the TQ5 smart phosgene fluorescent display material comes into contact with phosgene, its fluorescence turns on instantly as shown in the figure. b) The fluorescence response of the TQ5 fluorescent display filter paper to different concentrations of BTC; c) The TQ5 silica gel-supported fluorescent colorimetric material detects different concentrations of BTC solution; when the display material comes into contact with different concentrations of BTC solution, it exhibits different fluorescence intensities.

[0027] Figure 12 The fluorescence changes of TQ5 powder under natural light and 365 nm UV lamp after the addition of metal ions are shown.

[0028] Figure 13 This represents the adsorption rate of the dry powder of the multifunctional gel compound TQ5 on heavy metal ions in aqueous solution. 2 mg of the dry gel powder was weighed and added to 5 ml of an aqueous solution containing metal ions (2 × 10⁻⁶). -3 In M), after ultrasonic vibration for 1 hour, the supernatant was centrifuged and the ion content was tested. The final result was obtained from ICP (Inductively Coupled Plasma) data. 2 mg of TQ5 hydrogel powder was found to be effective against the toxic metal ion Cr. 3+ Co 3+ Cd 2+ Hg 2+ Ag + Pd 2+ The adsorption rate histogram. (See attached image.) Figure 13 TQ5 dry gel powder for Cd2+ Hg 2+ Ag + The adsorption rates can reach 80.85%, 91.64%, and 88.62%, respectively.

[0029] 6. Recognition and adsorption mechanism of metal cations by TQ5

[0030] Figure 14 This multifunctional compound TQ5 reacts with heavy metal ions Hg 2+ The host-guest NMR titration diagram. 0-2 equivalents of Hg were gradually added to TQ5. 2+ hour, 1 H NMR nuclear magnetic titration, such as Figure 14 As shown, Hg 2+ The added shielding effect caused a high-field shift in the hydrogen proton signal peak on the benzene ring, while TQ5 and Hg... 2+ The low-field shift in the hydrogen proton signal peaks on the quinoline ring is caused by the cation-π bonding mechanism.

[0031] In summary, this invention provides a multifunctional compound TQ5 based on tris(quinoline-5-methoxy-diachydrazido)benzene, which is used for highly sensitive detection of phosgene and triphosgene and efficient separation of heavy metal ions. (The concentration is 1×10⁻⁶) -5 When triphosgene solution was added to a TQ51,4-dioxane solution of M, the fluorescence of the solution at 365 nm changed from colorless to bright green. However, the fluorescence of solutions containing common volatile toxic gases did not change significantly upon addition. The detection limit of triphosgene reached 4.70 × 10⁻⁶. -8 M. Similarly, the same mechanism can be used for the detection and identification of highly toxic phosgene. Furthermore, this invention is based on TQ5 compound phosgene fluorescent colorimetric material for convenient, rapid, and highly sensitive detection of triphosgene and phosgene in real-world environments. Finally, TQ5 dry gel powder can be applied to the efficient detection and adsorption separation of heavy metal ions in water, including Cd. 2+ Hg 2+ Ag + The adsorption rates reached 80.85%, 91.64%, and 88.62%, respectively. This study provides a new method for developing multifunctional supramolecular smart materials for multi-substrate detection and separation, which has certain application prospects in the fields of food and environmental safety detection and control. Attached Figure Description

[0032] Figure 1 Mass spectrum of the multifunctional compound TQ5.

[0033] Figure 2 : The proton NMR spectrum of the multifunctional compound TQ5.

[0034] Figure 3Multifunctional compound TQ5 in 1,4-dioxane solution (1×10⁻⁶) -5 Fluorescence spectra of M before and after the addition of BTC (λex = 420 nm).

[0035] Figure 4 : TQ5 1,4-dioxane solution (1×10 -5 Fluorescence response of M to volatile organic gas solutions.

[0036] Figure 5 Multifunctional compound TQ5 in 1,4-dioxane solution (1×10⁻⁶) -5 Fluorescence titration spectrum of triphosgene (0-2 equivalents) in M) (λex = 420 nm).

[0037] Figure 6 Linear fitting curve of fluorescence titration of BTC in 1,4-dioxane solution of TQ5.

[0038] Figure 7 : Proton NMR titration of TQ5 with equivalence of triphosgene added gradually (a~g: 0-4.5 equiv).

[0039] Figure 8 : Reaction mechanism diagram of TQ5 with phosgene and triphosgene.

[0040] Figure 9 Mass spectrometry of the multifunctional compound TQ5 after reaction with triphosgene.

[0041] Figure 10 Scanning electron micrographs of TQ5 and the product of the reaction between TQ5 and phosgene in 1,4-dioxane.

[0042] Figure 11 a) TQ5 smart phosgene fluorescent display material under UV lamp (365 nm) irradiation; b) Fluorescence response of TQ5 fluorescent display filter paper to different concentrations of triphosgene (BTC); c) Detection of different concentrations of triphosgene using TQ5 silica gel-supported fluorescent colorimetric material.

[0043] Figure 12 Changes in the fluorescence of TQ5 powder under natural light and 365 nm UV lamp after the addition of metal ions.

[0044] Figure 13 Adsorption rate of heavy metal ions in aqueous solution by TQ5 gel dry powder (w%=1%).

[0045] Figure 14 TQ5 and Hg 2+ Nuclear magnetic titration. Detailed Implementation

[0046] The preparation of the multifunctional compound TQ5 of this invention and its application in fluorescence recognition of phosgene / triphosgene and adsorption and separation of heavy metal ions are further illustrated below through specific examples.

[0047] Example 1: Synthesis of the multifunctional compound TQ5.

[0048] (1) Synthesis of 2-(quinoline-5-oxy)acetylhydrazine: Take a 250 ml volumetric flask, place 5-hydroxyquinoline (1.4500 g, 0.01 mmol) and anhydrous potassium carbonate (2.0700 g, 0.015 mmol) in 100 ml acetone solution, stir at room temperature for 20 min, weigh ethyl chloroacetate (1.8300 g, 0.015 mmol), and reflux at 80 °C for 24 h under nitrogen atmosphere. After the reaction is complete, filter under reduced pressure, wash three times with DCM, and remove the filter cake. Separate and purify the solution by column chromatography (petroleum ether: ethyl acetate 5:1, v / v) to obtain a brown oily target compound, which turns into a pale yellow solid product Q5 after standing. Weigh Q5 (2.300 g, 0.0099 mmol) and mix thoroughly with 30 ml of anhydrous ethanol, add 6 ml of 80% hydrazine hydrate, and react at 80 °C for 8 h. After the reaction was complete, column chromatography (methanol:dichloromethane, 10:1, v / v) was used for separation and purification to obtain white flocculent solid Q5, with an overall yield of 70%.

[0049] (2) Synthesis of the multifunctional compound TQ5: 0.2656 g (1 mmol) of 1,3,5-pyromellitic acid chloride was dissolved in 50 mL of DCM, and 0.7161 g (3.3 mmol) of 2-(quinoline-5-oxy)acetylhydrazine was dissolved in 20 mL of DCM. A 250 mL round-bottom flask was used, and the DCM solution of 1,3,5-pyromellitic acid chloride was gradually added dropwise to the DCM solution of 2-(quinoline-5-oxy)acetylhydrazine. After stirring at room temperature for 24 hours, the mixture was washed three times with DCM and filtered under vacuum to obtain a pale yellow solid. Finally, it was purified by recrystallization with DMF and water, and dried in a vacuum oven at 60 °C to obtain the pale yellow solid TQ5. The yield was 86%. The mass spectrum and proton NMR spectrum of the multifunctional compound TQ5 are shown below. Figure 1 and Figure 2 .

[0050] The synthesis route for TQ5 is as follows:

[0051]

[0052] Example 2: TQ5 selectively identifies phosgene / triphosgene

[0053] Transfer 2 mL of a 1,4-dioxane solution of the multifunctional compound TQ5 molecule (C) TQ5= 1×10 -5 M), methanol, ethanol, acetone, benzene, toluene, formaldehyde, acetaldehyde, dichloromethane, ammonia, hydrazine hydrate, phenol, diethyl ether, carbon disulfide, and triphosgene in DMSO solution (C=0.1M) are added respectively. If the fluorescence of the 1,4-dioxane solution of the multifunctional compound TQ5 changes from colorless to bright green, it indicates that the added solution contains triphosgene solution. If the fluorescence does not change, it indicates that the added solution does not contain phosgene or triphosgene.

[0054] Example 3: TQ5 fluorescent colorimetric material used to identify phosgene and triphosgene

[0055] The multifunctional compound TQ5 was loaded onto filter paper or silica powder via an immersion method. When the fluorescent material came into contact with triphosgene solutions of different concentrations, it exhibited corresponding fluorescence activation. Figure 11 Meanwhile, this fluorescent colorimetric material emits a distinct bright green fluorescence when it comes into contact with highly toxic phosgene.

[0056] Example 4: TQ5 dry gel powder is used for efficient adsorption and separation of heavy metal ions.

[0057] The specific preparation method of TQ5 hydrogel powder is as follows: Weigh 10 mg of TQ5 and pour it into a 1.5 ml gel bottle, add 1 ml of H2O, and sonicate the system to form a hydrogel (w%=1%). Place the hydrogel in the air to dry naturally to obtain 10 mg of TQ5 hydrogel powder.

[0058] 2 mg of TQ5 dry gel powder was added to 5 ml (0.03 M) of a metal ion solution. After ultrasonic dispersion for 0.5 hours, the solution was centrifuged at high speed, and the supernatant was filtered through an organic phase membrane. This achieved the adsorption and separation of heavy metal ions in water. TQ5 dry gel powder showed good adsorption for Cd. 2+ Hg 2+ Ag + The adsorption rates can reach 80.85%, 91.64%, and 88.62%, respectively.

Claims

1. A multifunctional compound based on tris(quinoline-5-methoxy-diachydrazide)benzene, with the molecular formula C 42 H 33 N9O9, designated as TQ5, has the following structural formula: 。 2. The method for synthesizing the multifunctional compound based on tris(quinoline-5-methoxy-diazidyl)benzene as described in claim 1, wherein a DCM solution of 1,3,5-pyromellitic tricarboxylic acid chloride is added dropwise to a DCM solution of 2-(quinoline-5-oxy)acetylhydrazine, and after stirring at room temperature for 20-25 hours, the mixture is washed, filtered, purified by recrystallization with DMF and water, and dried under vacuum to obtain the multifunctional compound TQ5 based on tris(quinoline-5-methoxy-diazidyl)benzene; The structural formula of 2-(quinoline-5-oxy)acetylhydrazine is: .

3. The method for synthesizing the multifunctional compound as described in claim 2, characterized in that: The molar ratio of 1,3,5-trimethylbenzene chloride and 2-(quinoline-5-oxy)acetylhydrazine is 1:3 to 1:3.

3.

4. The application of the multifunctional compound based on tris(quinoline-5-methoxy-diachydrazido)benzene as described in claim 1 in the adsorption and separation of heavy metal ions, characterized in that: The heavy metal ion is Cd 2+ Hg 2+ Ag + .

5. The application of the multifunctional compound based on tris(quinoline-5-methoxy-diachydrazide)benzene as described in claim 1 in the preparation of phosgene / triphosgene fluorescent test strips.

6. The application as described in claim 5, characterized in that: In a solution of the multifunctional compound 1,4-dioxane, methanol, ethanol, acetone, benzene, toluene, formaldehyde, acetaldehyde, dichloromethane, ammonia, hydrazine hydrate, phenol, diethyl ether, carbon disulfide, and DMSO solution of triphosgene were added respectively. Only the addition of triphosgene caused the fluorescence of the 1,4-dioxane solution of the multifunctional compound to change from colorless to bright green.

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