Column [5] quinone compound, chromatographic column and preparation method and application thereof

Abstract

The invention discloses a column [5] quinone compound, a chromatographic column and a preparation method and application thereof, and belongs to the technical field of organic analysis materials. According to the method, column [5] arene is demethylated to generate column [5] arene complete hydroxyl, the column [5] arene complete hydroxyl further reacts with an oxidizing agent to generate column [5] quinone (Q5), gram-level preparation of Q5 can be achieved through the two-step reaction, and the synthesis yield reaches up to 96%. The Q5 is modified on an amino silicon ball to serve as a stationary phase material of a high performance liquid chromatographic column, and separation of eight typical aromatic nitro explosives and qualitative prediction of unknown nitro explosives can be realized in one chromatographic column. The method has the advantages that the raw materials of the column [5] quinone can be commercially purchased, the synthesis is simple and convenient, and the yield is high.

Description

Technical Field

[0001] The present invention relates to the technical field of organic analysis materials, and particularly relates to a column [5] quinone compound, a chromatographic column, a preparation method thereof and an application thereof. Background Art

[0002] At present, the detection methods for aromatic nitro explosives mainly include fluorescence spectroscopy (optical sensor), gas chromatography-mass spectrometry (GC-MS), high performance liquid chromatography (HPLC), etc. Due to the characteristics of thermal instability and high boiling point of aromatic nitro explosives, they are incompatible with gas chromatography. And high performance liquid chromatography is more suitable for the detection of aromatic nitro explosives because of its high resolution, high sensitivity and high repeatability. However, due to the complex composition of explosives, there are still few studies on the analysis of explosives by high performance liquid chromatography. Using two-dimensional high performance liquid chromatography to separate aromatic nitro explosives and connecting two chromatographic columns in series will result in higher detection costs. Therefore, separating various aromatic nitro explosives with a single column is an attractive method. The separation ability of a high performance liquid chromatography column depends on its stationary phase. Therefore, designing a new stationary phase material specifically for the separation of aromatic nitro explosives has important economic value and national defense significance. Summary of the Invention

[0003] The purpose of the present invention is to provide a column [5] quinone compound, a chromatographic column, a preparation method thereof and an application thereof. The column [5] arene pentahydroxy is synthesized from commercially available raw materials, and the column [5] quinone is obtained in high yield through room temperature oxidation. By modifying the column [5] quinone on silica spheres as a high performance liquid chromatography stationary phase material and further preparing a chromatographic column, it is possible to separate eight typical aromatic nitro explosives with a single chromatographic column and make predictions, which is superior to commercial double-column separation and is expected to fill the domestic blank of related similar products.

[0004] In order to achieve the above-mentioned invention purpose, the present invention provides the following technical solutions: The present invention provides a column [5] quinone compound, which is prepared by oxidizing a column [5] arene compound, and the structure of the column [5] quinone compound is shown in formula (I): .

[0005] On the one hand, the present invention also provides a preparation method of the above-mentioned column [5] quinone compound, and the preparation method includes the following steps: Using column [5] arene pentahydroxy as a raw material, dispersing it in a solvent, adding an oxidant, filtering by suction after the reaction is completed, and washing with the solvent to obtain the product Q5. The solvent is one of water, methanol, ethanol, acetonitrile, acetone, isopropanol, tetrahydrofuran, N,N-dimethylformamide, dimethyl sulfoxide, preferably water and dimethyl sulfoxide. The oxidant is potassium peroxymonosulfate (Oxone).

[0006] On the other hand, the present invention also provides a liquid chromatography column prepared from the above-mentioned pillar [5] quinone compound, and its characteristics include the following aspects: The structure of the Q5-Sil liquid chromatography column is shown in Formula (II): .

[0007] The present invention also provides a method for preparing a Q5-Sil liquid chromatography column, which is characterized in that the preparation method includes the following steps: Disperse Q5, amino silica spheres, and diaminotriphenyl in an organic solvent, mix them in a set ratio, heat and react, and then purify and dry to obtain Q5-modified silica spheres Q5-Sil. Prepare the obtained Q5-Sil into a suspension and pour it into a homogenization tank with a stainless steel column connected at the lower end. Install the homogenization tank on a column packing machine, pack the column under a certain pressure, remove the pressure, remove the chromatographic column, and screw on the column cap to obtain the Q5-Sil liquid chromatography column. The organic solvent is one of methanol, ethanol, acetonitrile, acetone, isopropanol, tetrahydrofuran, N,N-dimethylformamide, and dimethyl sulfoxide, and ethanol is preferred.

[0008] The present invention also provides an application of the above-mentioned Q5-Sil liquid chromatography column in the analysis and prediction of explosives. The experimental results show that the Q5-Sil liquid chromatography column has the ability to predict the explosion intensity of unknown aromatic nitro explosives to a certain extent.

[0009] The beneficial effects of the present invention compared with the prior art are as follows: The raw materials for preparing the pillar [5] quinone of the present invention are commercially available, the synthesis is simple, the yield is high, and the prepared Q5-Sil liquid chromatography column can achieve the separation and prediction of eight typical aromatic nitro explosives with a single chromatographic column, which is superior to the commercial double-column separation. Description of the Drawings

[0010] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings; Figure 1 It is the nuclear magnetic spectrum of pillar [5] quinone in Example 1; Figure 2 It is the characterization schematic diagram of the silica spheres used in the Q5-Sil liquid chromatography column in Example 2; where a: Thermogravimetric analysis of NH2-Sil and Q5-Sil; b: Fourier transform infrared spectra of NH2-Sil and Q5-Sil; c: Fourier transform infrared spectrum of Q5; Figure 3Schematic diagram of the structure of the Q5-Sil liquid chromatography column in Example 2; Figure 4 Results of the separation of explosives by the Q5-Sil liquid chromatography column in Example 3; where a: Liquid chromatogram of the separation of nitro explosives by the Q5-Sil packed column (2.1 mm × 150 mm, 5 μm). b: Van't Hoff plot of nitro explosives on the Q5-Sil liquid chromatography column; c: Simulated calculation of the surface electrostatic potential of Q5 and aromatic nitro explosives; (1: Nitrobenzene, 2: 2-Nitrotoluene, 3: 4-Nitrotoluene, 4: 3-Nitrotoluene, 5: m-Dinitrobenzene, 6: 2,4,6-Trinitrotoluene, 7: 2-Amino-4,6-dinitrotoluene, 8: 2,4,6-Trinitrotoluene). Detailed implementation manners

[0011] Now, various exemplary implementation manners of the present invention will be described in detail. This detailed description should not be regarded as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, characteristics, and implementation schemes of the present invention.

[0012] It should be understood that the terms described in the present invention are only for describing specific implementation manners and are not used to limit the present invention. Additionally, for the numerical ranges in the present invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each intermediate value within any stated value or stated range, as well as each smaller range between any other stated value or intermediate value within the stated range, is also included in the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0013] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention pertains. Although the present invention only describes preferred methods and materials, any methods and materials similar or equivalent to those described herein can also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In case of conflict with any incorporated document, the content of this specification shall prevail.

[0014] Without departing from the scope or spirit of the present invention, various improvements and changes can be made to the specific implementation manners of the description of the present invention, which are obvious to those skilled in the art. Other implementation manners obtained from the description of the present invention are obvious to those skilled in the art. The description of the present invention and the examples are only exemplary.

[0015] Regarding the terms "comprising", "including", "having", "containing", etc. used herein, they are all open-ended terms, meaning including but not limited to.

[0016] The raw materials used in the present invention (1,4-dimethoxybenzene and nitro compounds for separation) are all commercially available. The preparation methods of pillar[5]arene and pillar[5]arene fully hydroxylated are synthesized according to the literature (J. Org. Chem. 2011, 76, 328–331). This is hereby stated. Example

[0017] Example 1 of the present invention discloses a synthesis method of pillar[5]quinone, and the preparation route is as follows:

[0018] A pillar[5]quinone compound was prepared in Example 1 of the present invention, and the specific preparation method is as follows: A mixture of fully hydroxylated methoxypillar[5]arene (1.0 g, 1.6 mmol) and Oxone (10.0 g, 16 mmol) was added to a single-necked flask, and then a dimethyl sulfoxide-water (50 mL + 50 mL) mixed solution was added as the reaction solvent. Stir at room temperature, add iodobenzene (0.83 g, 4.0 mmol), and stir vigorously at room temperature for 1 day for post-treatment. After the reaction, the reaction system was poured into a 500 mL beaker, 200 mL of water was added, stirred for 5 min, and then left to stand. Most of the water in the upper layer was removed by decantation filtration. The solid-liquid mixture in the lower layer was filtered by suction and the solid was washed with dimethyl sulfoxide, dichloromethane, and water respectively. Finally, a yellow solid was obtained. It was dried in a vacuum drying oven at 55 °C to completely remove the residual solvent. Pure pillar[5]quinone (0.93 g) was obtained. Characterization data: 1 H NMR (400 MHz, CD3Cl) δ (ppm): 6.81 (s, 10H), 3.59 (s, 10H), see Figure 1 。 Example

[0019] Example 2 of the present invention discloses a preparation method of a pillar[5]quinone (Q5) compound chromatographic column, and the specific preparation method is as follows: Take 1.0 g of amino silica gel NH2-Sil, 0.1 g of 4,4'-diaminotriphenyl, 0.5 g of Q5, mix with ethanol and reflux for 72 h. The crude product of Q5-modified silica gel Q5-Sil was prepared. After washing with ethanol multiple times and filtering by suction, pure Q5-Sil was obtained. The product was placed in a vacuum drying oven and dried at 60 °C for 24 h before use.

[0020] Thermogravimetric analysis data showed that: for Q5-Sil, there was only a 2.5% weight loss before 100 °C, which was considered to be the dissociation of adsorbed water. There was approximately a 17.5% weight loss before 600 °C, indicating that the content of Q5 on NH2-Sil was about 15.0%. This showed that Q5 had a high grafting efficiency on the surface of NH2-Sil and could be used as the stationary phase for liquid chromatography. See Figure 2 a.

[0021] FT-IR spectroscopy was used to characterize the amino modification of Q5 and silica spheres and the preparation of Q5-Sil microspheres. The characteristic quinone group band of Q5 was at 1660 cm -1 (-C=O) ( Figure 2 c). Compared with the FT-IR spectrum of NH2-Sil, in the FT-IR spectrum of SiO2 after Q5 modification, there were the characteristic bands of the quinone group at 1660 cm -1 (-C=O) and the characteristic band of the formed carbon-nitrogen single bond at 1440 cm -1 (-C-N), and there was an obvious characteristic peak of Si-O-Si at 1060 cm -1 for both Q5-Sil and NH2-Sil, indicating that Q5 was successfully modified on NH2-Sil. See Figure 2 b-2c.

[0022] After thorough drying, 0.6 g of Q5-Sil was weighed into a 100 mL beaker, 50 mL of methanol was added, and it was ultrasonically dispersed for 5 min. The obtained suspension was poured into a homogenization tank with a stainless steel column (150 mm × 2.1 mm i.d.) at the lower end. The homogenization tank was installed on a column packing machine and packed at a pressure of 6000 psi. After removing the pressure, the chromatographic column was removed, the column cap was screwed on, and the Q5-Sil packed chromatographic column was obtained. The chromatographic column was connected to a Waters ACQUITY UPLC H-Class chromatograph and equilibrated with methanol at 0.2 mL min -1 for 2 h and then could be used for chromatographic separation. The structural schematic diagram is shown in Figure 3 . Example

[0023] Example 3 of the present invention discloses a method for the separation and prediction of explosives detection using a column [5] quinone (Q5) compound chromatographic column, specifically as follows: The chromatographic column was a self-made Q5-Sil liquid chromatographic column (2.1 mm × 150 mm, 5 μm); the mobile phase: methanol: water: glacial acetic acid (50:47.5:2.5); the flow rate was 0.2 mL / min; the injection volume was 2 μL. The detection wavelength was 254 nm. The column oven temperature was set at 30 °C.

[0024] We separated eight nitrobenzene derivatives, which are all the main components of explosives, using a Q5-Sil liquid chromatography column. Experiments have proven that the Q5-Sil liquid chromatography column has good retention and separation effects on nitrobenzene derivatives. As Figure 4 shown in Figure a, nitrobenzene, 2-nitrotoluene, 4-nitrotoluene, 3-nitrotoluene, m-dinitrobenzene, tetryl, 2-amino-4,6-dinitrotoluene, and trinitrotoluene were eluted in sequence for separation. The separation results show that as the number of nitro substitutions increases, their retention ability in the Q5-Sil liquid chromatography column increases in sequence, and the explosion intensity of nitro explosives gradually increases with the increase in the number of nitro groups. Based on this property, the explosion intensity of some nitro explosives can be predicted. According to the experimental results, we summarized a recommended formula for predicting the retention time of simple nitrobenzene derivatives on the Q5 chromatographic column: Time (min) = 5.4×logP + 7.3×Num(nitro group) + 6.5×Num(substituent group) - 15.6. (The logP value (polar interaction), the number of nitro groups (dipole interaction), and the number of substituent groups (steric hindrance) all contribute to increasing the retention time). To verify the universality of this invention, we selected 5 nitrobenzene derivatives with only alkyl substitutions: 1,3,5-trinitrobenzene, 1,3-dinitrobenzene, 2,5-dimethylnitrobenzene, 1-ethyl-3-nitrobenzene, and 4-ethylnitrobenzene. After experimental verification, the predicted values are close to the experimental values. Therefore, we can roughly estimate the danger level of an unknown nitro compound based on its separation time and take effective measures. This chromatographic column is expected to be applied to predict the danger level of nitro explosives.

[0025]

[0026] The present invention discloses a method for preparing gram-scale column [5] quinone with high yield, which has the advantages of commercially available raw materials, simple synthesis, and high yield. Column [5] quinone further reacts with amino silica spheres to obtain the stationary phase material of a high-performance liquid chromatography column. This chromatographic column can achieve single-column separation of nitro explosives and can quickly analyze and predict the types of unknown nitro explosives.

[0027] Aiming at the limitation that tandem chromatographic columns must be used for the detection of nitro explosives, a high-performance liquid chromatography column was prepared simply and efficiently, realizing single-column high-efficiency separation of nitro explosives. In addition, the explosion intensity of unknown nitro explosives can be further predicted based on the retention time of nitro compounds on this chromatographic column.

[0028] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Those skilled in the art understand that, without departing from the spirit and scope of the present invention, various equivalent substitutions, modifications or improvements can be made to the technical solutions and their implementation manners of the present invention, and all of these fall within the scope of the present invention. Additionally, it should be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction to avoid unnecessary repetition. Furthermore, any combination can be made between the various different embodiments of the present invention as long as it does not violate the idea of the present invention, and it should equally be regarded as the content disclosed by the present invention.

Claims

1. A method for synthesizing column [5] quinone (Q5), characterized in that The preparation method comprises the following steps: Using pillar[5]arene pentahydroxide as a raw material, dispersing it in a solvent, adding an oxidant, performing suction filtration after the reaction is completed, and washing with the solvent to obtain product Q5; the solvent is one of water, methanol, ethanol, acetonitrile, acetone, isopropanol, tetrahydrofuran, N,N-dimethylformamide, and dimethyl sulfoxide, preferably water and dimethyl sulfoxide; the oxidant is Oxone; The structure of the said pillar[5]quinone (Q5) is shown in formula (I): Formula (I).

2. A liquid chromatography column prepared by the Q5 synthesis method as described in claim 1, and its characteristics include the following aspects: The structure of the said Q5-Sil liquid chromatography column is shown in formula (II): Formula (II).

3. A method for preparing the Q5-Sil liquid chromatography column according to claim 2, characterized in that, The product prepared is a chromatography column, and the preparation method comprises the following steps: Using Q5, amino silica spheres, and diaminotriphenyl as raw materials, mixing and dispersing them in an organic solvent according to a set ratio, heating and reacting, and then purifying and drying to obtain modified silica spheres Q5-Sil; preparing the obtained Q5-Sil into a suspension and pouring it into a homogenizing tank with a stainless steel column connected at the lower end, installing the homogenizing tank on a column packing machine, packing the column under a certain pressure, removing the pressure, disassembling the chromatography column, and screwing on the column cap to obtain the Q5-Sil liquid chromatography column; the organic solvent is one of methanol, ethanol, acetonitrile, acetone, isopropanol, tetrahydrofuran, N,N-dimethylformamide, and dimethyl sulfoxide, preferably ethanol.

4. Application of the Q5-Sil liquid chromatography column prepared by the preparation method of the Q5-Sil liquid chromatography column as described in claim 2 or the Q5-Sil liquid chromatography column as described in claim 3 in the analysis and prediction of aromatic nitro explosives.

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