Imidazolium ionic liquid functionalized pillar[5]arene stationary phase, capillary gas chromatographic column and preparation method thereof

Abstract

The application discloses a capillary gas chromatographic column with an imidazole ionic liquid functionalized column pentaarene stationary phase and a preparation method of the column pentaarene stationary phase, and the chemical formula of the stationary phase is P5A-C4-IM-C1[NTf2], P5A-C10-IM-C1[NTf2], P5A-C4-IM-C8[NTf2] and P5A-C10-IM-C8[NTf2]. The preparation process of the imidazole ionic liquid functionalized column pentaarene stationary phase is characterized by mild reaction conditions, low cost of raw materials, novel structure of the stationary phase, obvious separation effect, stable final product, good performance, and the like, and the obtained final product can be used for accurate separation of halogenated benzene, aromatic aldehyde isomers and aromatic amine isomers.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of chromatographic analysis, and particularly relates to an imidazole ionic liquid functionalized column pentaarene stationary phase. BACKGROUND

[0002] In the past few decades, macrocyclic host molecules such as crown ethers, cyclodextrins, calixarenes and cucurbiturils have attracted much attention due to their typical cavity structure, host-guest recognition properties and wide range of applications. In 2008, a new type of columnar host molecule (column pentaarene) was first reported by Ogoshi and his colleagues. X-ray crystal analysis showed that column pentaarene was composed of five benzene ring units, which were bridged by methylene groups at their para positions. So far, researchers have isolated and characterized column pentaarene to column decaarene, among which column pentaarene has been widely studied due to its easy synthesis, high yield and good stability. Compared with typical host molecules, column arenes have the following advantages. First, compared with crown ethers and calixarenes, column arenes have a highly symmetrical columnar structure, which makes them have high selectivity for some guest molecules through non-covalent interactions; second, compared with cucurbiturils, column arenes are more easily derivatized, and different substituents can be introduced on all or part of the benzene rings to adjust their host-guest properties; third, compared with water-soluble cucurbiturils and cyclodextrins, column arenes are easily soluble in common organic solvents, making their applications more extensive.

[0003] Due to the excellent properties of column arenes, research on column arenes is rapidly expanding in many fields such as host-guest chemistry, coordination chemistry, artificial transmembrane channels, catalysts, sensors, etc. At the same time, the structure and properties of column arenes also make them good candidates for chromatographic separation stationary phases. However, column arenes are rarely studied in the field of chromatographic analysis, and the main reason may be that their high melting point and poor film-forming ability greatly limit the research and application of column arenes in this field. SUMMARY

[0004] The present application aims to solve the problem that it is difficult to use column arenes to prepare high selectivity and high inert chromatographic separation stationary phases in the prior art, and provides an imidazole ionic liquid functionalized column pentaarene stationary phase.

[0005] In order to solve the above technical problems, the specific solution adopted by the present application is as follows:

[0006] The imidazole ionic liquid functionalized column pentaarene stationary phase has a chemical formula of P5A-C4-IM-C1[NTf2], P5A-C10-IM-C1[NTf2], P5A-C4-IM-C8[NTf2] and P5A-C10-IM-C8[NTf2], and the chemical structural formula of the stationary phase is as follows:

[0007]

[0008]

[0009] The application also provides a preparation method of the above-mentioned imidazole ionic liquid functionalized pillar [5] quinoid stationary phase, comprising the following steps:

[0010] 1) reacting 1,4-hydroquinone, dibromodecane or dibromobutane, potassium carbonate, potassium iodide and 2-propanone, and after post-treatment and purification, a compound (I) is obtained;

[0011] 2) performing a cyclization reaction on the compound (I), paraformaldehyde, boron trifluoride ether and 1,2-dichloroethane, and after post-treatment and purification, an intermediate (II) is obtained;

[0012] 3) reacting the intermediate (II), 1-octyl imidazole or methyl imidazole and acetonitrile, and after post-treatment, an intermediate (III) is obtained;

[0013] 4) reacting the intermediate (III), lithium bistrifluoromethanesulfonimide and methanol, and after post-treatment, the imidazole ionic liquid functionalized pillar [5] quinoid stationary phase is obtained.

[0014] As a further optimization of the above-mentioned preparation method of the imidazole ionic liquid functionalized pillar [5] quinoid stationary phase, in step 1), the adding amount ratio of 1,4-hydroquinone, dibromodecane or dibromobutane, potassium carbonate, potassium iodide and 2-propanone is 1 mol:4 mol:1 mol:4 mol:35-40 mL, and column chromatography is used during purification, and the volume ratio of petroleum ether:dichloromethane in the eluent is 5:1.

[0015] As a further optimization of the above-mentioned preparation method of the imidazole ionic liquid functionalized pillar [5] quinoid stationary phase, in step 2), the reaction temperature is 35℃, the reaction time is 3-4 h, and the adding amount ratio of the compound (I), paraformaldehyde, boron trifluoride ether, 1,2-dichloroethane is 1 mol:3 mol:1 mol:48-50 mL, and column chromatography is used during purification, and the volume ratio of petroleum ether:dichloromethane in the eluent is 3:1.

[0016] As a further optimization of the above-mentioned preparation method of the imidazole ionic liquid functionalized pillar [5] quinoid stationary phase, in step 3), the reaction time is 7-8 d, and the adding amount ratio of the intermediate (II), 1-octyl imidazole or methyl imidazole and acetonitrile is 1 mol:20 mol:20 mL.

[0017] As a further optimization of the above-mentioned preparation method of the imidazole ionic liquid functionalized pillar [5] quinoid stationary phase, in step 4), the reaction temperature is 25℃, the reaction time is 3-4 d, and the adding amount ratio of the intermediate (III), lithium bistrifluoromethanesulfonimide and methanol is 1 mol:15-20 mol:20 mL.

[0018] The application also provides a capillary gas chromatographic column, which is prepared from the imidazole ionic liquid functionalized pentacene stationary phase.

[0019] As a further optimization of the capillary gas chromatographic column of the application: the preparation method of the capillary gas chromatographic column is static coating.

[0020] The imidazole ionic liquid functionalized pentacene stationary phase of the application has excellent chromatographic separation performance for halogenated benzene isomers, aromatic aldehyde isomers and aromatic amine isomers.

[0021] The halogenated benzene isomers include dichlorobenzene isomers, dibromobenzene isomers, chloronitrobenzene isomers and bromonitrobenzene isomers; the dichlorobenzene isomers include o-dichlorobenzene, m-dichlorobenzene and p-dichlorobenzene; the dibromobenzene isomers include o-dibromobenzene, m-dibromobenzene and p-dibromobenzene; the chloronitrobenzene isomers include o-chloronitrobenzene, m-chloronitrobenzene and p-chloronitrobenzene; the bromonitrobenzene isomers include o-bromonitrobenzene, m-bromonitrobenzene and p-bromonitrobenzene.

[0022] The aromatic aldehyde isomers include methylbenzaldehyde isomers, dichlorobenzaldehyde isomers, nitrobenzaldehyde isomers and hydroxybenzaldehyde isomers; the methylbenzaldehyde isomers include o-methylbenzaldehyde, m-methylbenzaldehyde and p-methylbenzaldehyde; the dichlorobenzaldehyde isomers include 2,3-dichlorobenzaldehyde, 2,4-dichlorobenzaldehyde, 2,5-dichlorobenzaldehyde, 2,6-dichlorobenzaldehyde and 3,4-dichlorobenzaldehyde; the nitrobenzaldehyde isomers include o-nitrobenzaldehyde, m-nitrobenzaldehyde and p-nitrobenzaldehyde; the hydroxybenzaldehyde isomers include o-hydroxybenzaldehyde, m-hydroxybenzaldehyde and p-hydroxybenzaldehyde.

[0023] The aromatic aniline isomers include toluidine isomers, dimethyl aniline isomers, iodoaniline isomers and phenylenediamine isomers; the toluidine isomers include o-toluidine, m-toluidine and p-toluidine; the dimethyl aniline isomers include 2,3-dimethyl aniline, 2,5-dimethyl aniline, 2,6-dimethyl aniline and 3,4-dimethyl aniline; the iodoaniline isomers include o-iodoaniline, m-iodoaniline and p-iodoaniline; the phenylenediamine isomers include o-phenylenediamine, m-phenylenediamine and p-phenylenediamine.

[0024] Compared with the prior art, the application has the following beneficial effects:

[0025] In this invention, the imidazole ionic liquid-functionalized column pentaaryl aromatic stationary phases P5A-C10-IM-C8[NTf2] and P5A-C4-IM-C8[NTf2] can accurately separate halogenated benzene isomers, aromatic aldehyde isomers, and aromatic amine isomers. This is because, compared with traditional macrocyclic compounds such as crown ethers, cucurbiturates, cyclodextrins, and calixarenes, column aromatics have a highly symmetrical columnar structure, exhibiting high selectivity for guest molecules through non-covalent interactions and being more easily derivatized. Their host-guest properties can be adjusted by introducing different substituents. The tail chain length (C8) of the imidazole ionic liquid-functionalized column pentaaryl aromatics has a significant impact on the selectivity and inertness of the chromatographic column. The introduction of octylimidazole ionic liquid significantly improves the separation performance of the column for aliphatic analytes of different polarities and aromatic compounds. Furthermore, the long alkyl chain (C10), as the connecting unit between the column aromatics and the ionic liquid, is beneficial for improving its separation performance and extends the retention time for nonpolar aliphatic analytes due to its enhanced van der Waals forces. Furthermore, it can achieve baseline separation of halobenzenes, aromatic aldehydes, and aromatic anilines. Therefore, due to the unique π-electron-rich cavity, amphiphilic structure, and excellent physicochemical properties of the imidazole ionic liquid-functionalized column pentaaryl aromatic stationary phase, multiple molecular recognition interactions exist between it and the analyte, including van der Waals forces, hydrogen bonds, dipole-dipole, CH…π, and π-π interactions. Thus, the imidazole ionic liquid-functionalized column pentaaryl aromatic stationary phase exhibits excellent chromatographic separation performance for halobenzene isomers, aromatic aldehyde isomers, and aromatic amine isomers. Attached Figure Description

[0026] Figure 1 This is a reaction route diagram of four imidazole ionic liquid-functionalized columnar aromatic hydrocarbons prepared from 1,4-hydroquinone as a raw material according to the present invention.

[0027] Figure 2 Thermogravimetric analysis comparison of four imidazole ionic liquid-functionalized pentaaryl aromatic stationary phases P5A-C10-IM-C8[NTf2], P5A-C4-IM-C8[NTf2], P5A-C10-IM-C1[NTf2], and P5A-C4-IM-C1[NTf2] with the control columns P5A-C10 and P5A-C4 is shown.

[0028] Figure 3 The graph shows a comparison of the column efficiency (Golay curves) of the four capillary gas chromatographic columns prepared in this invention and P5A-C10, measured at 120℃ using n-dodecane as a probe compound.

[0029] Figure 4 This is a chromatogram showing the separation of 15 aliphatic mixture samples of different polarities using four capillary gas chromatography columns prepared in this invention.

[0030] Figure 5This invention provides chromatograms showing the separation of different polarities and types of trimethylbenzene isomers: 1,3,5-trimethylbenzene, 1,2,4-trimethylbenzene, 1,2,3-trimethylbenzene; trichlorobenzene isomers: 1,3,5-trichlorobenzene, 1,2,4-trichlorobenzene, 1,2,3-trichlorobenzene; dimethylphenol isomers: 2,3-dimethylphenol, 2,5-dimethylphenol, 2,6-dimethylphenol, 3,4-dimethylphenol, 3,5-dimethylphenol; and methylnaphthalene isomers: 2-methylnaphthalene, 1-methylnaphthalene, using four capillary gas chromatography columns.

[0031] Figure 6 This is a comparison diagram of the separation of 18 complex mixture samples of different polarities and types by the two capillary gas chromatography columns P5A-C10-IM-C8[NTf2] and P5A-C4-IM-C8[NTf2] prepared in this invention, and the separation by commercial columns HP-5, HP-35 and DB-17.

[0032] Figure 7 This is a comparison chromatogram showing the separation of halobenzene isomers using two capillary gas chromatography columns, P5A-C10-IM-C8[NTf2] and P5A-C4-IM-C8[NTf2], prepared in this invention, and the separation using commercial columns HP-5, HP-35, and DB-17. The isomers include: dichlorobenzene isomers: o-dichlorobenzene, m-dichlorobenzene, and p-dichlorobenzene; dibromobenzene isomers: o-dibromobenzene, m-dibromobenzene, and p-dibromobenzene; chloronitrobenzene isomers: o-chloronitrobenzene, m-chloronitrobenzene, and p-chloronitrobenzene; and bromonitrobenzene isomers: o-bromonitrobenzene, m-bromonitrobenzene, and p-bromonitrobenzene.

[0033] Figure 8 This is a comparison chromatogram showing the separation of benzaldehyde isomers using two capillary gas chromatography columns, P5A-C10-IM-C8[NTf2] and P5A-C4-IM-C8[NTf2], prepared in this invention, compared with the separation using commercial columns HP-5, HP-35, and DB-17. The isomers include: methylbenzaldehyde isomers: o-methylbenzaldehyde, m-methylbenzaldehyde, and p-methylbenzaldehyde; dichlorobenzaldehyde isomers: 2,3-dichlorobenzaldehyde, 2,4-dichlorobenzaldehyde, 2,5-dichlorobenzaldehyde, 2,6-dichlorobenzaldehyde, and 3,4-dichlorobenzaldehyde; nitrobenzaldehyde isomers: o-nitrobenzaldehyde, m-nitrobenzaldehyde, and p-nitrobenzaldehyde; and hydroxybenzaldehyde isomers: o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, and p-hydroxybenzaldehyde.

[0034] Figure 9This is a comparison chromatogram showing the separation of aromatic aniline isomers using two capillary gas chromatography columns prepared in this invention, P5A-C10-IM-C8[NTf2] and P5A-C4-IM-C8[NTf2], compared with the separation using commercial columns HP-5, HP-35, and DB-17. The isomers include: toluidine isomers: o-toluidine, m-toluidine, and p-toluidine; dimethylaniline isomers: 2,3-dimethylaniline, 2,5-dimethylaniline, 2,6-dimethylaniline, and 3,4-dimethylaniline; iodoaniline isomers: o-iodoaniline, m-iodoaniline, and p-iodoaniline; and phenylenediamine isomers: o-phenylenediamine, m-phenylenediamine, and p-phenylenediamine.

[0035] Figure 10 The P5A-C10-IM-C8[NTf2] capillary gas chromatography column prepared in this invention separates 12 groups of cis-trans isomers with different polarities.

[0036] Figure 11 These are scanning electron microscope (SEM) images of the two capillary gas chromatography columns P5A-C10-IM-C8[NTf2] and P5A-C4-IM-C8[NTf2] prepared in this invention;

[0037] Figure 12 The P5A-C10-IM-C8[NTf2] capillary gas chromatographic column prepared in this invention is used to analyze and detect related isomer impurities in commercial analytical grade products, including 1,2,4-trichlorobenzene, 2,4-dimethylaniline, 2,5-dimethylaniline, 3,5-dimethylaniline, geraniol, cis-decahydronaphthalene, and trans-decahydronaphthalene. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0039] Example 1

[0040] (1) 2 g (18.16 mmol) of 1,4-hydroquinone, 21.80 g (72.65 mmol) of 1,10-dibromodecane, 2.51 g (18.16 mmol) of potassium carbonate, and 12.06 g (72.65 mmol) of potassium iodide were added to 80 mL of 2-propanone and reacted at 65 °C for 72 h. After cooling, the mixture was filtered, and the filter cake was washed with 100 mL of dichloromethane. The filtrate was collected and evaporated to dryness to obtain 24.250 g of a brown, viscous crude product. The product was purified by column chromatography with petroleum ether:dichloromethane = 5:1 (V:V) as the eluent to obtain compound (Ⅰ): 2.50 g. Compound (Ⅰ) is 1,4-bis(10-bromodecyloxy)benzene, and the structural formula of compound (Ⅰ) is as follows:

[0041]

[0042] (2) 2.00 g (3.65 mmol) of compound (Ⅰ), 0.33 g (10.94 mmol) of paraformaldehyde, 0.52 g (3.65 mmol) of boron trichloride diethyl ether and 50 mL of 1,2-dichloroethane were added to a 250 mL single-necked flask and reacted at 35 °C for 4 h. 50 mL of deionized water was added, and the organic phase was washed with 50 mL of saturated brine, dried over anhydrous magnesium sulfate, filtered, and evaporated to dryness to obtain 2.40 g of green crude product. The product was purified by column chromatography using petroleum ether:dichloromethane = 3:1 (V:V) to obtain intermediate (Ⅱ) as a white solid: 0.26 g. Intermediate (Ⅱ) is a brominated pentaary aromatic hydrocarbon. The structural formula of intermediate (Ⅱ) is as follows:

[0043]

[0044] (3) Add 0.2 g (0.07 mmol) of intermediate (II) and 0.26 g (1.40 mmol) of 1-octylimidazole obtained in step 2 to 20 mL of acetonitrile and react under N2 for 7 days. After the reaction is complete, evaporate the solvent, wash the crude product three times with 20 mL of ethyl acetate, filter, and obtain 0.26 g of intermediate (III) as a yellow solid. Intermediate (III) is a 1-octylimidazole bromide liquid-functionalized columnar pentaaryl aromatic hydrocarbon. The structural formula of intermediate (III) is:

[0045]

[0046] Its characterization data are: IR(KBr,cm -1 ):3064.18(CH3),2923.50(CH2),2853.80(CH2),1635.03(CN),1561.10(CN), 1496.59(C=C), 1457.99(C=C), 1375.85(C=C), 1159.12(COC), 1106.84(COC).

[0047] (4) Take 0.2 g (0.04 mmol) of intermediate (Ⅲ) and 0.25 g (0.87 mmol) of lithium bis(trifluoromethanesulfonylimide) obtained in step (3) and add them to 20 mL of methanol. Stir and react at 25 °C for 3 days. After evaporating the solvent, dissolve the residue in 20 mL of dichloromethane. Wash the organic phase three times with 20 mL of deionized water and dry with anhydrous magnesium sulfate to obtain 0.18 g of the final product (Ⅳ), a brown oily substance. The final product is an imidazole ionic liquid-functionalized columnar pentaaryl aromatic hydrocarbon with the chemical formula P5A-C10-IM-C8[NTf2]. The structural formula of the final product (Ⅳ) is...

[0048]

[0049] Its characterization data are as follows: 1 H NMR(300MHz,DMSO-d6)δ9.07(br,10H),7.71(br,10H),7.67(s,10H),6.76(br,10H),4.08(dq,J=13.3,7.1,6.6 Hz,40H),3.81(s,10H),3.62(s,20H),1.94–1.56(m,60H),1.38–0.98(m,218H),0.86–0.79(m,30H).IR(KBr,cm -1 ):2928.19(CH2),2856.84(CH2),1713.89(CN),1686.52(CN),1563.12(C=C),1498. 06(C=C),1469.45(C=C),1347.54(SO),1179.72(CF),1133.15(COC),1052.06(COC).

[0050] Example 2

[0051] (1) 2.50 g of 1,4-hydroquinone, 27.25 g of 1,10-dibromodecane, 3.14 g of potassium carbonate, and 15.08 g of potassium iodide were added to 85 mL of 2-propanone and reacted at 65 °C for 72 h. After cooling, the mixture was filtered, and the filter cake was washed with 100 mL of dichloromethane. The filtrate was collected and evaporated to dryness to obtain a yellow, viscous crude product. This product was purified by column chromatography with petroleum ether:dichloromethane = 5:1 (V:V) as the eluent to obtain compound (Ⅰ): 2.80 g.

[0052] (2) 2.50 g (1.82 mmol) of compound (Ⅰ), 0.16 g (5.47 mmol) of paraformaldehyde, 0.26 g (1.82 mmol) of boron trichloride ether and 60 mL of 1,2-dichloroethane were added to a 100 mL single-necked flask and reacted at 35 °C for 4 h. 50 mL of deionized water was added, and the organic phase was washed with 50 mL of saturated brine, dried over anhydrous magnesium sulfate, filtered, and evaporated to dryness to obtain 2.90 g of green crude product. The product was purified by column chromatography with petroleum ether:dichloromethane = 3:1 (V:V) to obtain intermediate (Ⅱ) white solid: 0.35 g.

[0053] (3) Add 0.3g (0.11mmol) of intermediate (II) and 0.39g (2.16mmol) of 1-octylimidazole obtained in step 2 to 20mL of acetonitrile and react under N2 for 7 days. After the reaction is completed, evaporate the solvent, wash the crude product three times with 20mL of ethyl acetate, filter, and obtain intermediate (III) yellow solid: 0.36g.

[0054] (4) Take 0.35 g (0.08 mmol) of intermediate (Ⅲ) and 0.45 g (1.55 mmol) of lithium bis(trifluoromethanesulfonylimide) obtained in step (3) and add them to 20 mL of methanol. Stir and react at 25 °C for 3 days. After evaporating the solvent, dissolve the residue in 20 mL of dichloromethane. Wash the organic phase three times with 20 mL of deionized water and dry with anhydrous magnesium sulfate to obtain 0.32 g of the final product P5A-C10-IM-C8[NTf2](Ⅳ) brown oil.

[0055] Example 3

[0056] (1) 3.00 g of 1,4-hydroquinone, 32.70 g of 1,10-dibromodecane, 3.27 g of potassium carbonate, and 18.09 g of potassium iodide were added to 100 mL of 2-propanone and reacted at 65 °C for 72 h. After cooling, the mixture was filtered, and the filter cake was washed with 100 mL of dichloromethane. The filtrate was collected and evaporated to dryness to obtain a yellow, viscous crude product. This product was purified by column chromatography with petroleum ether:dichloromethane = 5:1 (V:V) as the eluent to obtain compound (Ⅰ): 3.6 g.

[0057] (2) 2.00 g (3.65 mmol) of compound (Ⅰ), 0.33 g (10.94 mmol) of paraformaldehyde, 0.52 g (3.65 mmol) of boron trichloride ether and 50 mL of 1,2-dichloroethane were added to a 100 mL single-necked flask and reacted at 35 °C for 4 h. 50 mL of deionized water was added, and the organic phase was washed with 50 mL of saturated brine, dried over anhydrous magnesium sulfate, filtered, and evaporated to dryness to obtain 1.2 g of green crude product. The product was purified by column chromatography with petroleum ether:dichloromethane = 3:1 (V:V) to obtain intermediate (Ⅱ) white solid: 0.26 g.

[0058] (3) Add 0.25 g (0.09 mmol) of intermediate (II) and 0.32 g (1.77 mmol) of 1-octylimidazole obtained in step 2 to 20 mL of acetonitrile and react under N2 for 7 days. After the reaction is completed, evaporate the solvent, wash the crude product three times with 20 mL of ethyl acetate, filter, and obtain intermediate (III) yellow solid: 0.30 g.

[0059] (4) Take 0.25 g (0.06 mmol) of intermediate (Ⅲ) and 0.32 g (1.11 mmol) of lithium bis(trifluoromethanesulfonylimide) obtained in step (3) and add them to 20 mL of methanol. Stir and react at 25 °C for 3 days. After evaporating the solvent, dissolve the residue in 20 mL of dichloromethane. Wash the organic phase three times with 20 mL of deionized water and dry it with anhydrous magnesium sulfate to obtain 0.23 g of the final product P5A-C10-IM-C8[NTf2](Ⅳ) brown oil.

[0060] Example 4

[0061] (1) 3.00 g of 1,4-hydroquinone, 32.70 g of 1,4-dibromobutane, 3.27 g of potassium carbonate, and 18.09 g of potassium iodide were added to 100 mL of 2-propanone and reacted at 65 °C for 72 h. After cooling, the mixture was filtered, and the filter cake was washed with 100 mL of dichloromethane. The filtrate was collected and evaporated to dryness to obtain a yellow, viscous crude product. This product was purified by column chromatography using petroleum ether:dichloromethane = 5:1 (V:V) as the eluent to obtain compound (Ⅰ): 4.3 g. Its structural formula is as follows:

[0062]

[0063] (2) 0.99 g (2.60 mmol) of compound (Ⅰ), 0.23 g (7.81 mmol) of paraformaldehyde, 0.37 g (2.59 mmol) of boron trichloride diethyl ether, and 50 mL of 1,2-dichloroethane were added to a 100 mL single-necked flask and reacted at 35 °C for 3 h. 50 mL of deionized water was added, and the organic phase was washed with 50 mL of saturated brine, dried over anhydrous magnesium sulfate, filtered, and evaporated to dryness to obtain 1.2 g of green crude product. This product was purified by column chromatography using a petroleum ether:dichloromethane ratio of 3:1 (V:V) to obtain intermediate (Ⅱ), a white solid weighing 0.68 g. Its structural formula is as follows:

[0064]

[0065] (3) Add 0.20 g (0.10 mmol) of intermediate (II) obtained in step 2 and 0.37 g (2.00 mmol) of 1-octylimidazole to 20 mL of acetonitrile and react under N2 for 7 days. After the reaction is completed, evaporate the solvent, wash the crude product three times with 20 mL of ethyl acetate, filter, and obtain intermediate (III) yellow solid: 0.33 g, the structural formula of which is as follows:

[0066]

[0067] Its characterization data are: IR(KBr,cm -1):3064.18(CH3),2923.50(CH2),2853.80(CH2),1635.03(CN),1561.10(CN), 1496.59(C=C), 1457.99(C=C), 1375.85(C=C), 1159.12(COC), 1106.84(COC).

[0068] (4) Take 0.32 g (0.09 mmol) of intermediate (Ⅲ) and 0.49 g (1.70 mmol) of lithium bis(trifluoromethanesulfonylimide) obtained in step (3) and add them to 20 mL of methanol. Stir and react at 25 °C for 3 days. After evaporating the solvent, dissolve the residue in 20 mL of dichloromethane. Wash the organic phase three times with 20 mL of deionized water and dry with anhydrous magnesium sulfate to obtain 0.29 g of the final product P5A-C4-IM-C8[NTf2](Ⅳ) brown oil. Its structural formula is as follows:

[0069]

[0070] Its characterization data are as follows: 1 H NMR(300MHz, CDCl3)δ8.81(s,10H),7.56(s,20H),7.21(s,10H),4.31(s,20H),4.13(s,2 0H),3.90(s,20H),3.68(s,10H),2.10(s,40H),1.26(s,120H),0.88(s,30H).IR(KBr,cm -1 ): 2929.26(CH2), 2859.09(CH2), 1563.12(CN), 1498.06(C=C), 1469.45(C=C), 1347.54(SO), 1179.72(CF), 1133.15(COC), 1052.06(COC).

[0071] Example 5

[0072] (1) 2.50 g of 1,4-hydroquinone, 27.25 g of 1,10-dibromodecane, 3.14 g of potassium carbonate, and 15.08 g of potassium iodide were added to 85 mL of 2-propanone and reacted at 65 °C for 72 h. After cooling, the mixture was filtered, and the filter cake was washed with 100 mL of dichloromethane. The filtrate was collected and evaporated to dryness to obtain a yellow, viscous crude product. This product was purified by column chromatography with petroleum ether:dichloromethane = 5:1 (V:V) as the eluent to obtain compound (Ⅰ): 2.80 g.

[0073] Its structural formula is as follows:

[0074]

[0075] (2) Take 2.50 g (1.82 mmol) of the obtained compound (Ⅰ) and 0.16 g (5.47 mmol)

[0076] Paraformaldehyde, 0.26 g (1.82 mmol) of boron trichloride diethyl ether, and 60 mL of 1,2-dichloroethane were added to a 100 mL single-necked flask and reacted at 35 °C for 4 h. 50 mL of deionized water was added, and the organic phase was washed with 50 mL of saturated brine, dried over anhydrous magnesium sulfate, filtered, and evaporated to dryness to obtain 2.90 g of a green crude product. This product was purified by column chromatography using a petroleum ether:dichloromethane ratio of 3:1 (V:V) to give intermediate (II) as a white solid: 0.35 g. Its structural formula is as follows:

[0077]

[0078] (3) Add 0.25 g (0.09 mmol) of intermediate (II) and 0.15 g (1.80 mmol) of 1-methylimidazole obtained in step 2 to 20 mL of acetonitrile. React under N2 for 7 days. After the reaction is complete, evaporate the solvent, wash the crude product three times with 20 mL of ethyl acetate, filter, and obtain 0.28 g of intermediate (III) as a yellow solid. Its structural formula is as follows:

[0079]

[0080] Its characterization data are: IR(KBr,cm -1 ):3099.00(CH3),2925.53(CH2),2853.16(CH2),1633.51(CN),1571.56(C=C),1496.84(C=C),1468.28(C=C),1208.65(COC),1166.75(COC).

[0081] (4) Take 0.21 g (0.06 mmol) of intermediate (Ⅲ) and 0.36 g (1.25 mmol) of lithium bis(trifluoromethanesulfonylimide) obtained in step (3) and add them to 20 mL of dichloromethane. Stir and react at 25 °C for 3 days. After evaporating the solvent, dissolve the residue in 20 mL of dichloromethane. Wash the organic phase three times with 20 mL of deionized water and dry with anhydrous magnesium sulfate to obtain 0.06 g of the final product P5A-C10-IM-C1[NTf2](Ⅳ) brown oil.

[0082]

[0083] Its characterization data are as follows: 1H NMR(300MHz,CD3OD)δ9.05(s,3H),7.59(s,20H),6.91(s,10H),4.51–4.00(m,20H),3.96(s,40H ),3.82(s,10H),3.74(d,J=4.1Hz,10H),1.89(s,40H),1.60(s,20H),1.39(s,100H).IR(KBr,cm -1 ): 2921.36(CH2), 2855.17(CH2), 1572.57(CN), 1507.49(C=C), 1472.83(C=C), 1349.39(SO), 1184.66(CF), 1054.45(COC), 1030.49(COC).

[0084] Example 6

[0085] (1) 3.00 g of 1,4-hydroquinone, 32.70 g of 1,4-dibromobutane, 3.27 g of potassium carbonate, and 18.09 g of potassium iodide were added to 100 mL of 2-propanone and reacted at 65 °C for 72 h. After cooling, the mixture was filtered, and the filter cake was washed with 100 mL of dichloromethane. The filtrate was collected and evaporated to dryness to obtain a yellow, viscous crude product. This product was purified by column chromatography using petroleum ether:dichloromethane = 5:1 (V:V) as the eluent to obtain compound (Ⅰ): 4.3 g. Its structural formula is as follows:

[0086]

[0087] (2) 0.99 g (0.60 mmol) of compound (Ⅰ), 0.23 g (7.66 mmol) of paraformaldehyde, 0.37 g (2.59 mmol) of boron trichloride diethyl ether, and 50 mL of 1,2-dichloroethane were added to a 100 mL single-necked flask and reacted at 35 °C for 3 h. 50 mL of deionized water was added, and the organic phase was washed with 50 mL of saturated brine, dried over anhydrous magnesium sulfate, filtered, and evaporated to dryness to obtain 1.2 g of green crude product. This product was purified by column chromatography using a petroleum ether:dichloromethane ratio of 3:1 (V:V) to obtain intermediate (Ⅱ), a white solid weighing 0.68 g. Its structural formula is as follows:

[0088]

[0089] (3) Add 0.35 g (0.18 mmol) of intermediate (II) and 0.30 g (3.60 mmol) of 1-methylimidazole obtained in step 2 to 20 mL of acetonitrile, and react under N2 for 7 days. After the reaction is completed, evaporate the solvent, wash the crude product three times with 20 mL of ethyl acetate, filter, and obtain intermediate (III) yellow solid: 0.40 g, the structural formula of which is as follows:

[0090]

[0091] Its characterization data are: IR(KBr,cm -1 ):3090.60(CH3),2929.53(CH2),2868.46(CH2),1631.43(CN),1571.01(C=C),1497.95(C=C),1404.56(C=C),1207.32

[0092] (COC), 1165.23(COC).

[0093] (4) Take 0.15 g (0.05 mmol) of intermediate (Ⅲ) and 0.31 g (1.08 mmol) of lithium bis(trifluoromethanesulfonylimide) obtained in step (3) and add them to 20 mL of dichloromethane. Stir and react at 25 °C for 3 days. After evaporating the solvent, dissolve the residue in 20 mL of dichloromethane. Wash the organic phase three times with 20 mL of deionized water and dry with anhydrous magnesium sulfate to obtain 0.05 g of the final product P5A-C4-IM-C1[NTf2](Ⅳ) brown oil. Its structural formula is as follows:

[0094]

[0095] Its characterization data are as follows: 1 H NMR(300MHz,CD3OD)δ8.36(s,10H),7.45(s,10H),7.23(s,10H),6.86(s,10H),4.24(t,J=7.1Hz, 20H),3.97(s,20H),3.76(s,14H),3.68(s,26H),2.13(t,J=9.0Hz,20H),1.88(s,20H).IR(KBr,cm -1 ):2939.81(CH2),2875.38(CH2),1573.55(CN),1498.09(C=C),1474.57(C=C ),1406.47(C=C),1346.53(SO),1177.98(CF),1132.75(COC),1051.89(COC).

[0096] By introducing different substituents into the column aromatic structure for derivatization, its melting point can be lowered and its selectivity can be changed, thus obtaining a capillary gas chromatography column with high selectivity and high inertness.

[0097] The ease of synthesis and derivatization of columnar aromatics makes them suitable platforms for chemical modification. To find a feasible strategy for developing highly selective stationary phases with low melting points and good film-forming abilities for gas chromatography separation, we designed an approach that incorporates imidazole ionic liquid units into the three-dimensional rigid framework of columnar aromatics. Based on their complementary structures and properties, columnar aromatics functionalized with amphiphilic imidazole ionic liquids may exhibit synergistic properties of low melting points, good film-forming abilities, high inertness, unique selectivity, and high thermal stability.

[0098] This invention uses 1,4-hydroquinone as a raw material. First, compound (I) is obtained through an etherification reaction. Then, compound (I) and paraformaldehyde undergo a cyclization reaction to obtain intermediate (II). Next, intermediate (II) undergoes an amination reaction to obtain intermediate (III). Finally, intermediate (III) undergoes an ion exchange reaction to obtain an imidazole ionic liquid-functionalized columnar pentaaryl aromatic derivative P5A-C10-IM-C8[NTf2] (e.g.). Figure 1 The entire experimental process was conducted under mild reaction conditions, with inexpensive raw materials, a novel stationary phase structure, and significant separation effect, resulting in a stable and high-performance final product.

[0099] Introducing imidazole ionic liquids with longer tail chains and alkyl chains into calixarenes can significantly improve the film-forming ability and column inertness of the stationary phase, enrich the intermolecular selectivity between the stationary phase and the analyte, and enhance selectivity. Compared to calixarenes, columnar aromatics have a highly symmetrical columnar structure and exhibit high selectivity for guest molecules through non-covalent interactions. Therefore, we introduce alkyl chains and imidazole ionic liquids into the structure of columnar aromatics. Imidazole ionic liquid columnar aromatics stationary phases with longer tail chains (C8) exhibit better separation performance and column inertness. The long alkyl chain (C10) connecting the columnar aromatics and imidazole ionic liquid also contributes to improving the separation performance and selectivity of the chromatographic column.

[0100] like Figure 2 As shown, four imidazole ionic liquid-functionalized pentaary aromatic hydrocarbons, P5A-C10-IM-C8[NTf2], P5A-C4-IM-C8[NTf2], P5A-C10-IM-C1[NTf2], and P5A-C4-IM-C1[NTf2], exhibit good thermal stability as stationary phases in capillary gas chromatography columns, ranging from 339℃ to 360℃.

[0101] Example 7

[0102] A capillary chromatographic column is prepared using an imidazole ionic liquid-functionalized pentaaryl aromatic stationary phase provided by this invention. Specifically, it can be prepared by static coating, taking P5A-C10-IM-C8[NTf2] as an example:

[0103] (1) Cut a quartz capillary with a length of 5m and an inner diameter of 250μm. First, rinse it with dichloromethane for 10min, and then age it at 200℃ for 2-3h under nitrogen protection so that the impurities in the capillary column are released with the nitrogen flow at high temperature.

[0104] (2) Weigh 1.31g of ground NaCl powder and place it in 10mL of anhydrous methanol solution. Stir vigorously for 45min to obtain a saturated sodium chloride methanol solution. Add 6mL of the saturated solution to 8mL of chloroform solution under vigorous stirring, then add 0.6mL of anhydrous methanol solution and stir for 5min. Add another 8mL of chloroform solution and continue stirring for 2min to obtain a saturated colloidal solution.

[0105] (3) The saturated colloidal solution was forced into the capillary under a nitrogen pressure of 0.01-0.02 MPa. Then the solution in the column was blown out with nitrogen and recrystallized at 200 °C for 3 hours under nitrogen protection to complete the roughening of the inner surface of the capillary column.

[0106] (4) In this experiment, the static column preparation method was used. P5A-C10-IM-C8[NTf2] was dissolved in dichloromethane solution to prepare a stationary solution with a concentration of 0.15% (w / v). The stationary solution was ultrasonicated for 5 min to remove air bubbles.

[0107] (5) Use a syringe to push the stationary phase into the capillary column until the stationary phase fills the entire column. Then seal one end of the capillary and connect the other end to the vacuum system. In a constant temperature water bath at 40°C, the solvent will slowly evaporate and the stationary phase will be evenly dispersed on the inner wall of the capillary column.

[0108] (6) The coated capillary column was aged under nitrogen protection using a programmed temperature increase method: it was kept at 40℃ for 30 min, and then increased to 180℃ at a rate of 1℃ / min and kept for 7 h to complete the aging of the column and obtain the capillary gas chromatography column.

[0109] This invention is the first to select four imidazole ionic liquid-functionalized pentaary aromatic derivatives, P5A-C10-IM-C8[NTf2], P5A-C4-IM-C8[NTf2], P5A-C10-IM-C1[NTf2], and P5A-C4-IM-C1[NTf2], as chromatographic stationary phases. The capillary gas chromatography column prepared by the static coating method has high column efficiency.

[0110] The four imidazole ionic liquid-functionalized column pentaaryl aromatic derivatives prepared in this invention, namely P5A-C10-IM-C8[NTf2], P5A-C4-IM-C8[NTf2], P5A-C10-IM-C1[NTf2], and P5A-C4-IM-C1[NTf2], possess unique structures. The column rings, alkyl chains, and imidazole ionic liquid functional groups enable this stationary phase to exhibit good performance in practical applications. It also exhibits various weak interactions with different analytes, including van der Waals forces, hydrogen bonds, π-π interactions, dipole-dipole interactions, and CH-π interactions, resulting in excellent separation performance for the P5A-C10-IM-C8[NTf2] and P5A-C4-IM-C8[NTf2] columns.

[0111] This invention is the first to use P5A-C10-IM-C8[NTf2], P5A-C4-IM-C8[NTf2], P5A-C10-IM-C1[NTf2], and P5A-C4-IM-C1[NTf2] as stationary phases for capillary gas chromatography columns. These materials perfectly combine the structural characteristics of column pentaaryral hydrocarbons with the advantages of imidazole ionic liquid functionalization, making it possible to use this type of novel material as a stationary phase for capillary gas chromatography columns and providing a wider range of separation materials for chromatographic separation research.

[0112] Figure 11 These are scanning electron microscope (SEM) images of the P5A-C10-IM-C8[NTf2] and P5A-C4-IM-C8[NTf2] capillary chromatographic columns prepared in this invention. The imidazole ionic liquid-functionalized column pentaaryl aromatic derivatives prepared in this invention combine the unique molecular recognition ability of column aromatics with the advantages of alkyl and ionic liquid functionalization, and compensate for each other's shortcomings. Among them, the column aromatics have good rigidity, adjustable flexibility, and π-electron-rich column rings, and have a certain inductive fit ability, thus recognizing guest molecules. However, they have disadvantages such as high melting point and poor film-forming properties. The advantage of easy functionalization of column aromatics allows for the introduction of long alkyl chains and imidazole ionic liquids at the lower edge of the column aromatics, thereby improving the properties of column aromatics as gas chromatography stationary phases. Introducing long alkyl chains can lower the melting point of column aromatics and improve their film-forming properties. The partially substituted imidazole ionic liquids improve the selectivity of column aromatics as chromatographic stationary phases for target compounds while ensuring the stability of column aromatics.

[0113] <Separation Effect>

[0114] To analyze the separation performance of the capillary column, the following experiments were conducted on the capillary column provided by this invention:

[0115] (1) As Figure 3 As shown, the Golay curve of n-dodecane was determined using the capillary gas chromatography column prepared in Example 4. The specific chromatographic conditions were: column oven temperature 120°C, carrier gas: nitrogen, carrier gas flow rate: 0.3 mL / min, and minimum theoretical plate height: 0.195 mm.

[0116] (2) Separation of 15 aliphatic mixture samples with different polarities:

[0117] Fifteen aliphatic mixtures were selected as analytes, and the samples were separated using the capillary gas chromatography column prepared in Example 4. Chromatographic separation conditions: 40°C for 1 min, then increased to 160°C at a rate of 10°C / min, with a carrier gas flow rate of 0.6 mL / min.

[0118] Figure 4 This is a chromatogram of a 15-component aliphatic mixture separated by a capillary gas chromatography column. The components are: 1: n-Heptanal, 2: 1-Bromoheptane, 3: n-Dodecane, 4: 1-Heptanol, 5: Methyl octanoate, 6: 2-Nonanone, 7: n-Tetradecane, 8: 2-Decanone, 9: n-Pentadecanane, 10: n-Undecanal, 11: 1-Bromoundecane, 12: Methyl undecanoate, 13: 1-Undecanol, 14: Methyl dodecanoate, and 15: 1-Dodecanol. The separation performance is superior to that of P5A-C10 and P5A-C4 columns. Figure 9 As shown, the capillary gas chromatography column prepared in Example 4 has a good separation effect on the 15-component aliphatic mixture. The variety of analytes demonstrates that the P5A-C10-IM-C8[NTf2] and P5A-C4-IM-C8[NTf2] stationary phases are suitable for separating aliphatic mixtures, and the separation effect is better than that of the control columns P5A-C10 and P5A-C4.

[0119] (2) Separating aromatic isomers of different polarities and types:

[0120] Four different types and polarities of aromatic isomers were selected as analytes for separation, including trimethylbenzene isomers: 1,3,5-trimethylbenzene, 1,2,4-trimethylbenzene, and 1,2,3-trimethylbenzene; trichlorobenzene isomers: 1,3,5-trichlorobenzene, 1,2,4-trichlorobenzene, and 1,2,3-trichlorobenzene; dimethylphenol isomers: 2,3-dimethylphenol, 2,5-dimethylphenol, 2,6-dimethylphenol, 3,4-dimethylphenol, and 3,5-dimethylphenol; and methylnaphthalene isomers: 2-methylnaphthalene and 1-methylnaphthalene. The chromatographic separation conditions were: 40℃ for 1 min, then increased to 160℃ at a rate of 10℃ / min, with a carrier gas flow rate of 0.6 mL / min. The capillary column prepared in this invention can separate the components in different types and polarities of aromatic isomers.

[0121] (3) Separation of 18 complex mixture samples of different types and polarities:

[0122] Eighteen complex mixtures were selected as analytes, and the samples were separated using the capillary gas chromatography column prepared in Example 4. Chromatographic separation conditions: 40°C for 1 min, then increased to 160°C at a rate of 10°C / min, with a carrier gas flow rate of 0.6 mL / min.

[0123] Figure 6 This is a chromatogram of a complex mixture of 18 components separated by a capillary gas chromatography column. The components are: 1: 1,3,5-trimethylbenzene; 2: 1-bromoheptane; 3: methyl heptanoate; 4: 1-heptanol; 5: n-tetane; 6: 2-nonanone; 7: methyl nonananoate; 8: 1,4-dibromobenzene; 9: 1,4-methylbenzaldehyde; 10: 1,2-toluidine; 11: 1-bromoundecane; 12: 2,6-dimethylaniline; 13: 2,5-dimethylphenol; 14: 1,2-chloronitrobenzene; 15: 2,6-dimethylnaphthalene; 16: 3,4-dimethylphenol; 17: 1,3-bromoaniline; 18: 1,2-phenylenediamine. The separation performance is superior to commercial polysiloxane columns HP-5, HP-35, and DB-17. Figure 6 As shown, the capillary gas chromatography column prepared in Example 4 has a good separation effect on 18 complex mixtures. It has a wide variety of analytes and a wide range of polarities, demonstrating that the P5A-C10-IM-C8[NTf2] and P5A-C4-IM-C8[NTf2] stationary phases are suitable for separating complex mixtures of different types and polarities.

[0124] (4) Separation of halobenzene isomers:

[0125] Four different types and polarities of halogenated benzene isomers were selected as analytes for separation, including dichlorobenzene isomer, dibromobenzene isomer, chloronitrobenzene isomer, and bromonitrobenzene isomer. Chromatographic separation conditions: 40℃ for 1 min, then increased to 160℃ at a heating rate of 10℃ / min, and carrier gas flow rate of 0.6 mL / min.

[0126] Figure 7 The images show chromatograms of halobenzene isomers separated by two capillary gas chromatography columns prepared in Example 4, compared with commercial polysiloxane columns HP-35, HP-5 and DB-17, showing that the P5A-C10-IM-C8[NTf2] column can effectively separate halobenzene isomers.

[0127] (5) Separation of aromatic aldehyde isomers:

[0128] Four aromatic aldehyde isomers of different types and polarities were selected as analytes for separation, including methylbenzaldehyde isomers: o-methylbenzaldehyde, m-methylbenzaldehyde, and p-methylbenzaldehyde; dichlorobenzaldehyde isomers: 2,3-dichlorobenzaldehyde, 2,4-dichlorobenzaldehyde, 2,5-dichlorobenzaldehyde, 2,6-dichlorobenzaldehyde, and 3,4-dichlorobenzaldehyde; nitrobenzaldehyde isomers: o-nitrobenzaldehyde, m-nitrobenzaldehyde, and p-nitrobenzaldehyde; and hydroxybenzaldehyde isomers: o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, and p-hydroxybenzaldehyde. Chromatographic separation conditions were: 40℃ for 1 min, then increased to 160℃ at a rate of 10℃ / min, with a carrier gas flow rate of 0.6 mL / min. Figure 8 As shown, the P5A-C10-IM-C8[NTf2] chromatographic column prepared in this invention can separate aromatic aldehyde isomers.

[0129] (6) Separation of aromatic amine isomers:

[0130] Four aromatic amine isomers of different types and polarities were selected as analytes for separation, including toluidine isomers: o-toluidine, m-toluidine, and p-toluidine; dimethylaniline isomers: 2,3-dimethylaniline, 2,5-dimethylaniline, 2,6-dimethylaniline, and 3,4-dimethylaniline; iodoaniline isomers: o-iodoaniline, m-iodoaniline, and p-iodoaniline; and phenylenediamine isomers: o-phenylenediamine, m-phenylenediamine, and p-phenylenediamine. Chromatographic separation conditions were: 40℃ for 1 min, then increased to 160℃ at a rate of 10℃ / min, with a carrier gas flow rate of 0.6 mL / min. Figure 9As shown, the P5A-C10-IM-C8[NTf2] chromatographic column prepared in this invention can separate aromatic amine isomers. This is because the π-electron-rich cavity, amphiphilic structure, excellent physicochemical properties, and multiple intermolecular interactions (π-π, CH-π, hydrogen bonds, dipole-dipole, and dispersion forces) of P5A-C10-IM-C8[NTf2] improve the separation ability of P5A-C10-IM-C8[NTf2] for mixtures of aromatic amines, aromatic aldehydes, and halobenzene isomers. Furthermore, the long alkyl chain between the column pentaaryl aromatic hydrocarbon and the imidazole ionic liquid can improve the film-forming properties of the stationary phase and the inertness of the chromatographic column.

[0131] (7) Separation of 12 groups of cis-trans isomers:

[0132] Twelve groups of cis-trans isomers of different types and polarities were selected as analytes. The above isomers were separated using the P5A-C10-IM-C8[NTf2] capillary gas chromatography column prepared in Example 4. The chromatographic separation conditions were: 40℃ for 1 min, then heated to 160℃ at a rate of 10℃ / min, and the carrier gas flow rate was 0.6 mL / min.

[0133] Figure 10 This is a chromatogram of 12 groups of cis-trans isomers of different types and polarities separated by a P5A-C10-IM-C8[NTf2] capillary gas chromatographic column prepared in Example 4, wherein a: cis-crotonyl chloride, trans-crotonyl chloride; b: cis-2-buten-1,4-diol, trans-2-buten-1,4-diol; c: cis-nerolidol, trans-nerolidol; d: cis-nerolidol, trans-nerolidol; e: cis-decahydronaphthalene, trans-decahydronaphthalene; f: cis-2,5-dimethyltetrahydrofuran, trans-2,5-dimethyltetrahydrofuran; g: cis-2 ,5-Dihydro-2,5-Dimethoxyfuran, trans-2,5-Dihydro-2,5-Dimethoxyfuran, h: cis-dihydrojasmonic acid methyl ester, trans-dihydrojasmonic acid methyl ester, i: cis-α-pentylcinnamaldehyde, trans-α-pentylcinnamaldehyde, j: cis-4-tert-butylcyclohexanol, trans-4-tert-butylcyclohexanol, k: cis-3,3,5-trimethylcyclohexane salicylate, trans-3,3,5-trimethylcyclohexane salicylate, l: cis-2-methyl-4-propyl-1,3-oxothiacyclohexane, trans-2-methyl-4-propyl-1,3-oxothiacyclohexane, such as Figure 10 As shown, the capillary gas chromatography column prepared in Example 4 can completely separate each group of cis-trans isomers, demonstrating the advantages of the P5A-C10-IM-C8[NTf2] stationary phase in separating cis-trans isomers, with rapid and efficient separation.

[0134] (8) Application in determining isomer impurities in real samples

[0135] Seven actual samples were selected as analytes, including 1,2,4-trichlorobenzene, 2,4-dimethylaniline, 2,5-dimethylaniline, 3,5-dimethylaniline, geraniol, cis-decahydronaphthalene, and trans-decahydronaphthalene. The above isomers were separated using a P5A-C10-IM-C8[NTf2] capillary gas chromatographic column prepared in Example 4. The chromatographic separation conditions were: 40°C for 1 min, then increased to 160°C at a rate of 10°C / min, with a carrier gas flow rate of 0.6 mL / min. Figure 12 As shown in Table 1 below, the purity test results of the P5A-C10-IM-C8[NTf2] chromatographic column prepared in this invention are basically consistent with the label purity of each sample, indicating that the P5A-C10-IM-C8[NTf2] chromatographic column has good potential and feasibility in detecting isomer impurities in actual samples.

[0136]

[0137] It should be noted that the above embodiments are only used to illustrate the present invention, but the present invention is not limited to the above embodiments. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. An imidazole ionic liquid-functionalized column pentaaryl aromatic hydrocarbon stationary phase, characterized in that: The chemical formula of the stationary phase is P5A-C4-IM-C8[NTf2] or P5A-C10-IM-C8[NTf2], and the chemical structural formula of the stationary phase is as follows: 。 2. The method for preparing the imidazole ionic liquid-functionalized columnar pentaaryl aromatic stationary phase as described in claim 1, characterized in that, Includes the following steps: 1) React 1,4-hydroquinone, dibromodecane or dibromobutane, potassium carbonate, potassium iodide and 2-acetone. After post-treatment and purification, the product is used to obtain compound (Ⅰ). 2) Compound (Ⅰ), paraformaldehyde, boron trifluoride ether and 1,2-dichloroethane were subjected to a cyclization reaction. After post-processing and purification, intermediate (Ⅱ) was obtained. 3) Take intermediate (II), 1-octylimidazole, and acetonitrile and react them. After post-treatment, the product is used to obtain intermediate (III). 4) Take intermediate (Ⅲ), lithium bis(trifluoromethanesulfonylimide) and methanol and react them. After post-treatment, the product is used to obtain the imidazole ionic liquid-functionalized columnar pentaaryl aromatic stationary phase.

3. A capillary gas chromatographic column, characterized in that, The capillary gas chromatography column was prepared from the imidazole ionic liquid-functionalized column pentaaryl aromatic stationary phase as described in claim 1.

4. A capillary gas chromatography column as described in claim 3, characterized in that, The capillary gas chromatography column was prepared by static coating.

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