Use of multifunctional hemicyanine compounds for discriminating organic solvents
By adding a multifunctional hemicyanine compound to an organic solvent, and utilizing color change, spectral scanning, and fluorescence observation, the problem of the complexity of identifying multiple organic solvents in existing technologies has been solved, and a rapid and economical solvent identification method has been achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- TAIZHOU UNIV
- Filing Date
- 2023-02-01
- Publication Date
- 2026-07-14
AI Technical Summary
Existing methods for identifying multiple organic solvents require large-scale experimental instruments and are complex, time-consuming, and labor-intensive, lacking cost-effective and simple analytical methods.
By adding different types of solvents to organic solvents using multifunctional hemicyanine compounds, ethyl acetate, ethanol, and dichloromethane can be rapidly identified by observing color changes with the naked eye, scanning with ultraviolet-visible light spectroscopy, or observing fluorescence color under ultraviolet light.
It enables rapid and economical identification of various organic solvents, especially ethyl acetate, ethanol, and dichloromethane. The operation is simple and has good scientific research and practical application value.
Smart Images
Figure CN116087182B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of analytical testing technology, specifically to a novel use of a known hemicyanine compound in identifying various organic solvents. Background Technology
[0002] Over the past century, the development of chemistry has effectively improved people's lives. In particular, the emergence of modern medicines and new materials has raised people's material standards, increased their happiness, and extended their lifespan. However, the development of chemistry is inseparable from the use of organic solvents. Most organic solvents serve as chemical raw materials and reaction media, possessing immense industrial value and being indispensable in human production processes. Visually, most organic solvents are colorless and transparent liquids. Identification methods primarily include gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS), which generally require the combined use of multiple large-scale experimental instruments, making them time-consuming and labor-intensive. Therefore, it is essential to find an economical, convenient analytical method capable of identifying multiple types of organic solvents.
[0003] In view of the above, this application is hereby submitted. Summary of the Invention
[0004] This application provides a novel application of multifunctional hemicyanine compounds in the identification of various organic solvents. The identification method is simple to operate and has good scientific research and practical application value.
[0005] The structural formula of the multifunctional hemicyanine compound involved in this application is shown in formula (I):
[0006]
[0007] Application of a multifunctional hemicyanine compound with the structural formula shown in formula (I) in the identification of organic solvents.
[0008] Application of a multifunctional hemicyanine compound with the structural formula shown in formula (I) in the preparation of reagents or kits for identifying organic solvents.
[0009] Optionally, the organic solvent is ethyl acetate, dichloromethane, or ethanol.
[0010] In experiments, the inventors of this application discovered that when hemicyanine compounds with the structural formula shown in formula (I) were added to different types of test solvents (1,4-dioxane, tetrahydrofuran, ethyl acetate, dichloromethane, chloroform, acetone, dimethyl sulfoxide, N,N-dimethylformamide, acetonitrile, glycerol, ethanol, methanol, and water), and after mixing and standing at room temperature for 18 hours, the tetrahydrofuran, ethyl acetate, and N,N-dimethylformamide solvents changed from blue or purple solutions to colorless. Further research on the color-removing solvents revealed that, compared to the other two solvents, the ethyl acetate solution showed the most significant color fading after 1 hour.
[0011] Based on this discovery, this application also provides a method for identifying ethyl acetate, comprising:
[0012] Add the hemicyanine compound with the structural formula shown in formula (I) to the ethyl acetate standard, mix well, and observe the color change of the solution with the naked eye for 1 hour, as a standard control;
[0013] Then, add the structural formula (I) to the solvent to be tested, mix well, observe the color change of the solution with the naked eye after 1 hour, and compare it with the color of the solution of the standard control.
[0014] Optionally, if the color change of the solution is consistent after 1 hour, the solution to be tested can be determined to be ethyl acetate.
[0015] Secondly, the inventors of this application discovered in experiments that when hemicyanine compounds with the structural formula shown in formula (I) are added to different types of test solvents (1,4-dioxane, tetrahydrofuran, ethyl acetate, dichloromethane, chloroform, acetone, dimethyl sulfoxide, N,N-dimethylformamide, acetonitrile, glycerol, ethanol, methanol, and water) and mixed thoroughly, the resulting mixed solutions are scanned in the wavelength range of 450–750 nm using a UV-Vis spectrophotometer to detect the optimal absorption wavelength and absorption intensity of the hemicyanine compounds in each solvent. It was found that the optimal absorption wavelength of the hemicyanine compounds in dichloromethane solvent is 676 nm, and the absorption intensity is highest at 676 nm.
[0016] Based on this discovery, this application also provides a method for identifying dichloromethane, comprising:
[0017] Add the hemicyanine compound with the structural formula shown in formula (I) to dichloromethane standard and mix well; perform ultraviolet-visible spectral scanning on the resulting mixed solution at 450-750 nm, record the optimal absorption wavelength and the absorption intensity at that wavelength, and use it as a standard control.
[0018] Then, add a hemicyanine compound with the structural formula shown in formula (I) to the solvent to be tested and mix well; after treating the resulting mixture under the same conditions as the standard control, record the optimal absorption wavelength and absorption intensity of the resulting mixture at that wavelength, and compare it with the optimal absorption wavelength and absorption intensity of the standard control at that wavelength.
[0019] Optionally, when comparing absorption intensity, if the optimal absorption wavelength of the test solution is within ±2 nm of the optimal emission wavelength of the standard control and the absorption intensity value is 90-110% of the absorption intensity value of the standard control, the test solution is determined to be dichloromethane.
[0020] Optionally, the optimal emission wavelength for the standard comparison is 676 nm.
[0021] Finally, the inventors of this application discovered in experiments that when the hemicyanine compound with the structural formula shown in formula (I) was added to different types of test solvents (1,4-dioxane, tetrahydrofuran, ethyl acetate, dichloromethane, chloroform, acetone, dimethyl sulfoxide, N,N-dimethylformamide, acetonitrile, glycerol, ethanol, methanol, and water) and mixed well, the sample was irradiated with a handheld ultraviolet lamp at 365 nm under dark conditions, and the fluorescence color was observed with the naked eye. It was found that compared with other solvents, the hemicyanine compound with the structural formula shown in formula (I) exhibited the strongest light blue fluorescence in ethanol.
[0022] Based on this discovery, this application also provides a method for identifying ethanol, comprising:
[0023] Add the hemicyanine compound with the structural formula shown in formula (I) to the ethanol standard and mix well; irradiate the sample under dark conditions with a 365nm ultraviolet lamp and observe the fluorescence color with the naked eye as a standard control.
[0024] Then, add a hemicyanine compound with the structural formula shown in formula (I) to the solvent to be tested and mix well; after treating the resulting mixed solution under the same conditions as the standard control, observe it with the naked eye and compare it with the fluorescence color of the standard control.
[0025] Optionally, when comparing fluorescence colors, if the colors are consistent when observed with the naked eye, the solution to be tested can be determined to be ethanol.
[0026] Optionally, the standard control exhibits a pale blue fluorescence.
[0027] This application provides a method for preparing hemicyanine derivatives, comprising:
[0028] Compounds (II) and (III) were reacted under nitrogen atmosphere with ethanol as solvent and piperidine as basic reagent. After the reaction, the target compound with the structural formula (I) was separated by column chromatography.
[0029]
[0030] The synthesis route is as follows:
[0031]
[0032] Optionally, the molar ratio of compound (II) to compound (III) is 1:0.9 to 1.
[0033] Optionally, when compound (II) is used at a dose of 0.5 mmol, the amount of piperidine used is 3 to 5 drops.
[0034] Preferably, the molar ratio of compound (II) to compound (III) is 1:0.9.
[0035] Optionally, the reaction conditions are: 40℃~80℃, stirring for 4h~8h.
[0036] Preferably, the reaction conditions are: 60℃, stirring for 6 hours.
[0037] Optionally, the separation and purification method may be as follows: the reaction solution is concentrated under reduced pressure, and separation and purification are carried out by column chromatography, using dichloromethane:methanol with a volume ratio of 30:1 as the eluent to obtain compound (I).
[0038] Compound (II) of this application is a disclosed compound, and its preparation method can be found in the literature "Simultaneous imaging of mitochondrial viscosity and hydrogen peroxide in Alzheimer's disease by a single near-infrared fluorescent probe with a large Stokesshift. Chemical. Communication, 2020, 56(7), 1050-1053".
[0039] Compound (III) of this application is a disclosed compound, and its preparation method can be found in the literature Facile incorporation of Pd(PPh3)2Hal substituents into polymethines, merocyanines, and perylene diimides as a means of suppressing intermolecular interactions. Journal of the American Chemical Society, 2016, 138(32), 10112-10115.
[0040] This application has at least the following beneficial effects:
[0041] (1) This application found that hemicyanine compounds with the structural formula shown in formula (I) can be rapidly, efficiently and economically identified from many colorless solvents by different means. The operation method is simple and has good scientific research and practical application value.
[0042] (2) This application found that hemicyanine compounds can be identified from a number of unknown single solvents by ultraviolet-visible light spectral scanning to determine whether they are dichloromethane; they can be identified from a number of unknown single solvents by observing the fluorescence color and brightness under ultraviolet light irradiation at 365nm; and they can be identified from a number of unknown single solvents by observing the color change of the compound in the solvent before and after 1 hour. Attached Figure Description
[0043] Figure 1 The 1H NMR spectrum of compound (I) prepared in Example 1 of this application.
[0044] Figure 2 High-resolution mass spectra of compound (I) prepared in Example 1 of this application.
[0045] Figure 3 The fluorescence images of compound (I) prepared in Example 1, observed by the naked eye under a handheld UV lamp in different test solvents.
[0046] Figure 4 The UV-Vis absorption spectra of compound (I) prepared in Example 1 in different test solvents are shown.
[0047] Figure 5 The images show the initial and 18-hour visual color of compound (I) prepared in Example 1 in different solvents.
[0048] Figure 6 The naked-eye color observation of compound (I) prepared in Example 1 in tetrahydrofuran, ethyl acetate, and N,N-dimethylformamide at the initial stage and after 1 hour. Detailed Implementation
[0049] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.
[0051] Example 1: Preparation of hemicyanine compound (I)
[0052] In a nitrogen atmosphere, compounds (II) and (III) were added to a sufficient amount of ethanol solution at a molar ratio of 1:0.9, and 3 to 5 drops of piperidine were added, with 0.5 mmol of compound (II) and 10 mL of ethanol. The mixture was stirred at 60 °C for 6 h. The reaction mixture was concentrated under reduced pressure and purified by silica column chromatography with dichloromethane / methanol (v / v, 30:1) to obtain hemicyanine compound (I) (yield 42%).
[0053] Synthesis route:
[0054]
[0055] 1 H NMR (400MHz, DMSO-d6) δ8.71(d,J=15.7Hz,1H),8.41(d,J=8.6Hz,1H),8.26(d,J=8.9Hz,1H),8.19(d,J=8.4Hz,1H),8.14(d,J=3.8Hz,1H),8.05(dd,J =8.9,1.8Hz,1H),7.73–7.58(m,5H),7.11(d,J=15.8Hz,1H),6.86–6.79(m,2H),4.15(s,3H),3.03(d,J=1.8Hz,6H),2.00(s,6H).HRMS(ESI)calcd.For C 29 H 29 N2S[M] + 437.2046, found 437.2049.
[0056] Its 1H NMR spectrum is shown in [reference needed]. Figure 1 For high-resolution mass spectrometry, see [link to high-resolution mass spectrometry]. Figure 2 .
[0057] Example 2: Application of hemicyanine compound (I) (8 μM) in the identification of ethanol solvent.
[0058] Accurately weigh a certain amount of the hemicyanine compound with the structural formula shown in formula (I) (prepared in Example 1), prepare a 1 mM stock solution with dimethyl sulfoxide, and pipette 32 μL into 4 mL of different solvents (1-13 are: 1,4-dioxane, tetrahydrofuran, ethyl acetate, dichloromethane, chloroform, acetone, dimethyl sulfoxide, N,N-dimethylformamide, acetonitrile, glycerol, ethanol, methanol, and water, respectively). After shaking and mixing, proceed as follows:
[0059] Irradiate the sample at 365nm using a handheld UV lamp in dark conditions and observe the fluorescence color with the naked eye; the results are as follows. Figure 3 As shown, by Figure 3It was found that when the sample was irradiated with a handheld UV lamp at 365nm under dark conditions and the fluorescence color was observed with the naked eye, ethanol showed the strongest pale blue fluorescence; the other colors were as follows: 1,4-dioxane, tetrahydrofuran, ethyl acetate, dimethyl sulfoxide, and N,N-dimethylformamide showed light blue fluorescence, dichloromethane, chloroform, and acetonitrile showed blue-violet fluorescence, acetone showed purple-blue fluorescence, glycerol showed light purple fluorescence, and methanol and water showed purple fluorescence.
[0060] Depend on Figure 3 The results show that, compared with other solvents, hemicyanine compound (I) exhibits the strongest pale blue fluorescence in ethanol, which is the most different from other colors and the easiest to distinguish.
[0061] For unknown types of test solvents, accurately weigh a certain amount of the hemicyanine compound with the structural formula shown in formula (I), prepare a 1 mM stock solution with dimethyl sulfoxide, pipette 32 μL and add it to 4 mL of the test solvent (unknown type), shake to mix, and then irradiate the sample at 365 nm with a handheld UV lamp in the dark and observe the fluorescence color with the naked eye. If the color observed by the naked eye is similar to... Figure 3 If the color matches that of ethanol, then the solvent being tested can be identified as ethanol.
[0062] Example 3: Application of hemicyanine compound (I) (8 μM) in the identification of dichloromethane solvent.
[0063] Accurately weigh a certain amount of the hemicyanine compound with the structural formula shown in formula (I) (prepared in Example 1), prepare a 1 mM stock solution with dimethyl sulfoxide, and pipette 32 μL into 4 mL of different solvents (1-13 are: 1,4-dioxane, tetrahydrofuran, ethyl acetate, dichloromethane, chloroform, acetone, dimethyl sulfoxide, N,N-dimethylformamide, acetonitrile, glycerol, ethanol, methanol, and water, respectively). After shaking and mixing, proceed as follows:
[0064] The resulting mixed solution was scanned using a UV-Vis spectrophotometer in the wavelength range of 450–750 nm, and the optimal absorption wavelength and absorption intensity at that wavelength were recorded; the results are as follows. Figure 4 As shown, the optimal emission wavelength of the hemicyanine compound in dichloromethane was found to be 676 nm, with an absorption intensity of 0.394.
[0065] In summary, the above data indicate that the probe has the ability to distinguish dichloromethane.
[0066] For unknown solvents, accurately weigh a certain amount of the hemicyanine compound with the structural formula shown in formula (I), prepare a 1 mM stock solution with dimethyl sulfoxide, pipette 32 μL and add it to 4 mL of the test solvent (unknown type), shake to mix, and then perform a spectral scan of the resulting mixed solution in the UV-Vis band of 450–750 nm. Compare the optimal absorption wavelength and the absorption intensity at the optimal absorption wavelength with... Figure 4 The solvent is compared to determine whether it is dichloromethane.
[0067] When comparing absorption intensities, if the optimal absorption wavelength of the test solution is within 676 nm ± 2 nm of the optimal emission wavelength of the standard control and the absorption intensity value is 90–110% of the standard control absorption intensity value, the test solution is determined to be dichloromethane.
[0068] Example 4: Application of hemicyanine compound (I) (8 μM) in the identification of ethyl acetate solvent.
[0069] Accurately weigh a certain amount of the hemicyanine compound with the structural formula shown in formula (I), prepare a 1 mM stock solution with dimethyl sulfoxide, and pipette 32 μL into 4 mL of different solvents (1-13 are 1,4-dioxane, tetrahydrofuran, ethyl acetate, dichloromethane, chloroform, acetone, dimethyl sulfoxide, N,N-dimethylformamide, acetonitrile, glycerol, ethanol, methanol, and water, respectively). After shaking and mixing, proceed as follows:
[0070] like Figure 5 After being left at room temperature for 18 hours, the solutions of tetrahydrofuran, ethyl acetate, and N,N-dimethylformamide changed from blue or purple to colorless. Further research on the color-removing solvents revealed that, for example... Figure 6 Compared to the other two solvents, the ethyl acetate solution showed the most significant decolorization after 1 hour.
[0071] In summary, the above data indicate that hemicyanine compounds have the ability to distinguish ethyl acetate.
[0072] For unknown solvents, accurately weigh a certain amount of the hemicyanine compound with the structural formula shown in formula (I), prepare a 1 mM stock solution with dimethyl sulfoxide, pipette 32 μL and add it to 4 mL of the test solvent (unknown type). After shaking and mixing, observe the color change of the solution visually for 1 hour, using this as a standard control. Then, add the structural formula shown in formula (I) to the test solvent, mix well, observe the color change of the solution visually for 1 hour, and compare it with the color of the standard control solution. Figure 6 The solvent is compared to determine whether it is ethyl acetate.
[0073] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.
Claims
1. The application of a multifunctional hemicyanine compound with the structural formula shown in formula (I) in the identification of organic solvents, characterized in that, The organic solvent is ethyl acetate, dichloromethane, and ethanol. （I）； The identification of ethyl acetate includes: Add the hemicyanine compound with the structural formula shown in formula (I) to the ethyl acetate standard, shake and mix well. The initial color is blue. After 1 hour, the solution fades to light purple. Record the color change as a standard control. Then add the hemicyanine compound with the structural formula shown in formula (I) to the solvent to be tested, mix well; observe the color change of the solvent and compare it with the color change of the standard control. If the color change is consistent after 1 hour, the solution to be tested is ethyl acetate. Identifying dichloromethane includes: Add the hemicyanine compound with the structural formula shown in formula (I) to dichloromethane standard and mix well; perform ultraviolet-visible spectral scanning on the resulting mixed solution at 450~750nm, record the optimal absorption wavelength of 676nm and the absorption intensity at that wavelength as a standard control; Then, add the hemicyanine compound with the structural formula shown in formula (I) to the solvent to be tested and mix well; after treating the resulting mixture under the same conditions as the standard control, record the optimal absorption wavelength and absorption intensity of the resulting mixture at that wavelength, and compare it with the optimal absorption wavelength and absorption intensity of the standard control at that wavelength. When comparing absorption intensity, if the optimal absorption wavelength of the test solution is within ±2nm of the optimal absorption wavelength of the standard control and the absorption intensity value is 90~110% of the absorption intensity value of the standard control, the test solution is determined to be dichloromethane. Identifying ethanol includes: Add the hemicyanine compound with the structural formula shown in formula (I) to the ethanol standard and mix well; irradiate the sample under dark conditions with a 365nm ultraviolet lamp and observe the fluorescence color with the naked eye as a standard control; Then, add the hemicyanine compound with the structural formula shown in formula (I) to the solvent to be tested and mix well; after treating the resulting mixed solution under the same conditions as the standard control, observe it with the naked eye and compare it with the fluorescence color of the standard control; When comparing fluorescence colors, if the colors are consistent when observed with the naked eye, the test solution can be determined to be ethanol. During the identification of the three substances, the amount of hemicyanine compound added was calculated based on its final concentration of 8-9 μM.