Application of COF material based on C = C bond connection in preparation of chiral chromatography stationary phase
阅读说明：本技术 基于c=c键连接的cof材料用于制作手性色谱固定相的应用 (Application of COF material based on C = C bond connection in preparation of chiral chromatography stationary phase ) 是由 崔勇 袁晨 刘玉豪 刘燕 于 2021-10-14 设计创作，主要内容包括：本发明涉及基于C＝C键连接的COF材料用于制作手性色谱固定相的应用。使用冠醚功能化的二联萘四醛基单体,基于Knoevenagel缩合反应合成C＝C键连接的手性COF；使用“网包法”将COF与硅胶复合,制得高效液相色谱手性固定相；使用动态涂敷法将COF均匀涂敷在气相色谱柱上,用作气相色谱手性固定相；将高效液相色谱柱或气相色谱柱用于多种类外消旋化合物的分离。与现有技术相比,得益于合成得到的C＝C键连接COF的高稳定性,本发明中制备得到的液相色谱柱与气相色谱柱,在手性分离过程中均表现出良好的分离能力和耐用性,解决了现有手性固定相仅适用于特定一种色谱的问题,开发了可同时用于液相色谱和气相色谱的新型高性能手性分离材料,具有潜在的应用前景。(The invention relates to application of COF (chip on film) materials based on C ═ C bond connection in preparation of chiral chromatographic stationary phases. Synthesizing a chiral COF (COF) with a C-bond connection based on a Knoevenagel condensation reaction by using a crown ether functionalized bigeminal naphthalene tetraaldehyde monomer; compounding COF and silica gel by using a 'network wrapping method' to prepare a chiral stationary phase of the high performance liquid chromatography; uniformly coating COF on a gas chromatography column by using a dynamic coating method to serve as a chiral stationary phase of the gas chromatography; high performance liquid chromatography columns or gas chromatography columns are used for the separation of the various racemic compounds. Compared with the prior art, the liquid chromatographic column and the gas chromatographic column prepared in the invention have good separation capability and durability in the chiral separation process due to the high stability of COF connected by the synthesized C ═ C bond, so that the problem that the existing chiral stationary phase is only suitable for a specific chromatogram is solved, a novel high-performance chiral separation material which can be used for both liquid chromatogram and gas chromatogram is developed, and the potential application prospect is realized.)
1. The application of COF material based on C ═ C bond connection in preparing chiral chromatographic stationary phase is characterized in that COF-1 or COF-2 is selected based on COF material based on C ═ C bond connection,
the structural formula of the COF-1 is as follows:
the structural formula of the COF-2 is as follows:
2. the use of COF materials based on C ═ C bond linkage as in claim 1 for making chiral chromatographic stationary phase, characterized in that COF materials based on C ═ C bond linkage are used for making chiral liquid chromatographic stationary phase, and COF materials based on C ═ C bond linkage are compounded with silica gel using "network packing method" to make COF chiral stationary phase for high performance liquid chromatography.
3. The use of COF materials based on C ═ C bond linkage according to claim 2 for making chiral chromatographic stationary phases, characterized in that the "pack method" for preparing COF chiral stationary phases is: grinding the COF material based on the C ═ C bond connection to obtain COF powder, then weighing silica gel and suspending the silica gel in a normal hexane solution of 1,3, 5-benzenetricarboxychloride, adding the ground COF powder, and completely evaporating the normal hexane after stirring; preparing an aqueous solution of piperazine, adding the aqueous solution of piperazine into the silica gel treated in the previous step, stirring to ensure that the silica gel is fully contacted with water, soaking, stirring at intervals after soaking is started to ensure that the silica gel is fully contacted with the water, standing to ensure that the silica gel is settled, pouring out the excess aqueous solution, and performing heat treatment on the polymerized silica gel to prepare the chiral stationary phase.
4. The use of COF materials based on C ═ C bond linkage according to claim 2 for making chiral chromatographic stationary phase, characterized in that COF materials based on C ═ C bond linkage are compounded with silica gel using "pack method" to make COF chiral stationary phase useful for high performance liquid chromatography, and then COF chiral stationary phase useful for high performance liquid chromatography is packed into high performance liquid chromatography column using high pressure homogenate column packing machine.
5. The use of COF materials based on C ═ C bond linkage according to claim 4 for the manufacture of chiral chromatographic stationary phases, characterized in that the packing of high performance liquid chromatography columns with a high pressure homogenization column packing machine is performed by: placing the prepared COF chiral stationary phase which can be used for high performance liquid chromatography in methanol for suspension, uniformly dispersing silica gel, rapidly pouring the silica gel into a homogenizing tank, taking methanol as a displacement liquid, keeping the methanol at the pressure of 30MPa for 5min, adjusting the pressure to 10-15 MPa, keeping the pressure for 30min, slowly releasing the pressure, and finally installing a sieve plate and a column head of a chromatographic column.
6. Use of a C ═ C bond based COF material for making chiral chromatographic stationary phases according to claim 1, characterized in that the C ═ C bond based COF material, as chiral gas chromatographic stationary phase, can be applied on the tube wall of a gas chromatographic column for use.
7. The use of COF materials based on C ═ C bond linkage according to claim 6 for making chiral chromatographic stationary phase, characterized in that as chiral gas chromatographic stationary phase, the COF materials based on C ═ C bond linkage are applied on the tube wall of gas chromatographic column by the following method:
weighing COF material powder based on C ═ C bond connection and OV-1701, grinding by using a ball mill, adding ethanol to prepare a suspension, introducing the suspension into an open capillary column under the condition of adding air pressure, pushing the liquid through the capillary column, and leaving a wet coating on the inner wall of the capillary column; a buffer tube is connected to the tail of the capillary column to serve as a flow restrictor, so that the solution is prevented from accelerating in flow rate near the tail end of the column; after the coating was completed, the coated column was flushed with nitrogen, programmed to warm, and finally the column was continuously activated.
8. Use of COF materials based on C ═ C bond linkage according to claim 1 for the preparation of chiral chromatographic stationary phases, characterized in that after the COF materials based on C ═ C bond linkage are used for the preparation of chiral chromatographic stationary phases, chromatographic columns are prepared for the chromatographic separation of racemic compounds.
9. Use of COF materials based on C ═ C bond linkage according to claim 8 for the preparation of chiral chromatographic stationary phases, characterized in that said racemic compounds comprise one or several of amino acids, lipids, lactones, amines, alcohols, aldehydes, ketones, olefinic compounds or chiral drug molecules; chiral drug molecules include warfarin, metoprolol, and pindolol.
10. Use of a C ═ C bond based COF material according to claim 8 for making chiral chromatographic stationary phases, characterized in that the column is used in a chiral separation process enabling baseline separation on: serine, 1- (1-naphthyl) ethanol, alanine and 1, 2-epoxyoctane.
Technical Field
The invention belongs to the field of chiral chromatographic separation, and particularly relates to an application of a COF material based on C ═ C bond connection in preparation of a chiral chromatographic stationary phase.
Background
Chirality is one of the basic attributes of nature, and chiral compounds relate to aspects of human life, in particular to the pharmaceutical industry, the food industry and the pesticide industry. The potency of two enantiomers in a chiral drug is often different and sometimes even diametrically opposite. Therefore, the separation of the optically pure single chiral compound is realized, and the method has great significance for human beings. Chromatographic separation is currently one of the most common and popular chiral separation methods, and scientists have developed a wide variety of chiral stationary phases for chiral chromatographic separation, some of which are commercially available. However, it has not been found that the same chiral material has excellent chiral selectivity in both high resolution gas chromatography and high performance liquid chromatography. For example, in high performance liquid chromatography, the most widely used commercial chiral column of cellulose tris (3, 5-dimethylphenyl isocyanate) has very excellent chiral separation capacity in normal phase liquid chromatography, the chiral selectivity in reverse phase liquid chromatography is obviously reduced, the amino acid enantiomer basically has no chiral recognition capacity, and the separation capacity is limited when the chiral column is used as a chiral stationary phase of gas chromatography; for another example, (R) - (3,3 '-diphenyl-1, 1' -dinaphthyl) -20-crown-6 is the liquid chromatography chiral column with the best effect of resolving amino acid at present, but when the chiral column is used as a gas chromatography chiral stationary phase, the separation capacity is lower; for example, in gas chromatography, the most widely used at present is an all-methyl-beta-cyclodextrin capillary chiral separation column, but no research report that the all-methyl-beta-cyclodextrin capillary chiral separation column is immobilized on a substrate as a liquid chromatography chiral stationary phase is found so far.
The Covalent Organic Framework (COF) is a crystalline porous framework material formed by connecting organic precursors through covalent bonds, has the advantages of rich construction units, orderly and regular structure, various covalent bond connection modes, permanent porosity and the like, and becomes one of the star materials. The COF material with C ═ C bond connection has the advantages of high chemical and physical stability, can meet the application under different eluent conditions and different temperature conditions, and has unique advantages when being used as a chromatographic stationary phase. However, COF materials have the disadvantages of too low density, irregular morphology, non-uniform particle size, etc., which seriously hinders the application of COF materials as stationary phases in the field of chromatographic separation. The currently reported COF as a chromatographic column filled with a chiral stationary phase often faces the problems of high column pressure, low column efficiency, long separation time and the like.
Therefore, the synthesis of high-stability COF rich in chiral action sites and the adoption of a proper column packing method to realize the high-efficiency chiral separation application of the COF in liquid chromatography and gas chromatography are imperative.
Disclosure of Invention
The invention aims to provide an application of a COF material based on C ═ C bond connection in preparation of a chiral chromatographic stationary phase.
The COF material based on the C ═ C bond connection is a high-stability material, can be used as a chiral stationary phase to be applied to liquid chromatography and gas chromatography, and can realize the separation of various racemic compounds under different eluent conditions. The invention solves the problems of strict use conditions and single type of separated substrate of the existing chiral stationary phase, and has wide development and application prospects.
The purpose of the invention can be realized by the following technical scheme:
the invention provides an application of a COF material based on C ═ C bond connection in preparing a chiral chromatographic stationary phase, the COF material based on C ═ C bond connection selects COF-1 or COF-2,
the structural formula of the COF-1 is as follows:
the structural formula of the COF-2 is as follows:
in one embodiment of the present invention, COF materials based on C ═ C bond bonds are prepared by a process comprising: the chiral COF-1 or COF-2 with C ═ C bond connection is synthesized by using a crown ether functionalized binaphthalene tetraaldehyde monomer and terephthalonitrile or 4, 4' -biphenyldiacetonitrile through a Knoevenagel condensation reaction.
The structural formula of the crown ether functionalized bi-binaphthyl tetraaldehyde monomer is as follows:
in one embodiment of the present invention, a method for preparing COF materials based on C ═ C bond linkage, comprises the following steps:
mixing a crown ether functionalized binaphthalene tetracarboxyl monomer, terephthalonitrile or 4, 4' -biphenyl diacetonitrile, dioxane and methanol, heating to a reaction temperature under a vacuum sealing condition, reacting, cooling the mixture to room temperature after the reaction, filtering to obtain a powdery solid, and then washing and drying to obtain COF-1 or COF-2.
In one embodiment of the present invention, one exemplary implementation condition is given based on the method of preparing a COF material in a C ═ C bond connection:
crown ether functionalized bis-naphthaldehyde monomer (30mg, 0.027mmol), terephthalonitrile (8.3mg, 0.053mmol) or 4, 4' -biphenyldiacetonitrile (12.4mg,0.053mmol), dioxane (0.5mL), methanol (0.5mL) were mixed in a 10mL Schlenk tube. The Schlenk tube was vacuum sealed and heated to 120 ℃ for 4 days. The mixture was cooled to room temperature and filtered to give a powdery solid, which was then washed 3 times with deionized water, tetrahydrofuran and diethyl ether, respectively, and dried under vacuum overnight at 60 ℃ to give COF-1 or COF-2.
In one embodiment of the invention, a COF material based on C ═ C bond connection is used for preparing a chiral liquid chromatography stationary phase, and the COF material based on C ═ C bond connection is compounded with silica gel by using a 'network coating method' to prepare the COF chiral stationary phase for high performance liquid chromatography, wherein the COF material based on C ═ C bond connection is selected from COF-1 or COF-2.
In one embodiment of the present invention, the method for preparing COF chiral stationary phase by "net-packing method" is: grinding the COF material based on the C ═ C bond connection to obtain COF powder, then weighing silica gel and suspending the silica gel in a normal hexane solution of 1,3, 5-benzenetricarboxychloride, adding the ground COF powder, and completely evaporating the normal hexane after stirring; preparing an aqueous solution of piperazine, adding the aqueous solution of piperazine into the silica gel treated in the previous step, stirring to ensure that the silica gel is fully contacted with water, soaking, stirring at intervals after soaking is started to ensure that the silica gel is fully contacted with the water, standing to ensure that the silica gel is settled, pouring out the excess aqueous solution, and placing the polymerized silica gel for heat treatment to prepare the chiral stationary phase.
In one embodiment of the present invention, the "screen pack method" for preparing COF chiral stationary phases gives an exemplary implementation condition: the COF material based on C ═ C bond linkage was ground to obtain COF powder with uniform size and smaller particle size, then 3.0g of silica gel was weighed and suspended in a solution of 1,3, 5-benzenetricarboxylic acid chloride in n-hexane (50mL, 0.05mmol), 0.9g of ground COF-1 or COF-2 powder was added, and after stirring for 30 minutes, n-hexane was evaporated to completion. Preparing an aqueous solution of piperazine (50mL, 0.46mol/L), adding the aqueous solution into the silica gel treated in the previous step, stirring to ensure that the silica gel is fully contacted with water, soaking for 2 hours, stirring once every 5min for 15min of beginning soaking to ensure that the silica gel is fully contacted with the water phase, standing to ensure that the silica gel is settled, and finally pouring out the redundant aqueous solution. And (3) placing the polymerized silica gel in an oven at 110 ℃ for heat treatment for 10min to prepare the chiral stationary phase 1 or 2.
In one embodiment of the invention, after the COF material based on the C ═ C bond connection is compounded with silica gel by using a "network packing method" to prepare the COF chiral stationary phase for high performance liquid chromatography, the COF chiral stationary phase for high performance liquid chromatography is packed into a high performance liquid chromatography column by using a high-pressure homogenate column packing machine.
In one embodiment of the present invention, the method for packing the high performance liquid chromatography column by using the high pressure homogenate column packing machine comprises the following steps: placing the prepared COF chiral stationary phase which can be used for high performance liquid chromatography in methanol for suspension, uniformly dispersing silica gel, rapidly pouring the silica gel into a homogenizing tank, taking methanol as a displacement liquid, keeping the methanol at the pressure of 30MPa for 5min, adjusting the pressure to 10-15 MPa, keeping the pressure for 30min, slowly releasing the pressure, and finally installing a sieve plate and a column head of a chromatographic column.
In one embodiment of the present invention, packing of a high performance liquid chromatography column using a high pressure homogenization column packing machine gives an exemplary implementation condition: 3.5g of the chiral stationary phase prepared by the method is weighed, placed in 25mL of methanol for suspension, so that the silica gel is uniformly dispersed and quickly poured into a homogenizing tank. And (3) keeping the methanol as a displacement liquid under the pressure of 30MPa for 5min, adjusting the pressure to 10-15 MPa, keeping the pressure for 30min, and finally slowly releasing the pressure, and finally installing a sieve plate and a column head of the chromatographic column. The size of the high performance liquid chromatography column used was: length: 250 mm; inner diameter: 4.6 mm.
In one embodiment of the invention, a COF material based on C ═ C bond linkage is used for making the chiral gas chromatography stationary phase, and the COF material based on C ═ C bond linkage as the chiral gas chromatography stationary phase can be coated on the tube wall of a gas chromatography column for use.
In one embodiment of the present invention, the COF material based on C ═ C bond connection is used as a chiral gas chromatography stationary phase, and the method for coating on the tube wall of a gas chromatography column is as follows:
weighing COF material powder based on C ═ C bond connection and OV-1701, grinding by using a ball mill, adding ethanol to prepare a suspension, introducing the suspension into an open capillary column under the condition of adding air pressure, pushing the liquid through the capillary column, and leaving a wet coating on the inner wall of the capillary column; a buffer tube is connected to the tail of the capillary column to serve as a flow restrictor, so that the solution is prevented from accelerating in flow rate near the tail end of the column; after the coating was completed, the coated column was flushed with nitrogen, programmed to warm, and finally the column was continuously activated.
In one embodiment of the present invention, the use of the C ═ C bond based COF material as a chiral gas chromatography stationary phase coated on the tube wall of a gas chromatography column gives one exemplary implementation condition:
weighing 3mg COF powder and 6mg OV-1701, grinding with a ball mill, adding 2ml ethanol to make a suspension, introducing the suspension into an open capillary column under added pressure, and pushing the liquid through the capillary column at a rate of 50cm/min, leaving a wet coating on the inner wall of the capillary column. A buffer tube with the length of 2m is connected to the tail of the capillary column to serve as a flow restrictor, so that the solution is prevented from accelerating near the tail end of the column. After the coating was complete, the coated column was flushed with nitrogen for 6h, programmed (1 ℃/min) from 30 ℃ to 300 ℃, and finally the column was activated continuously at 300 ℃ for 3 h. The chromatographic column size is: length: 15 m; inner diameter: 0.25 mm.
In one embodiment of the invention, after the COF material based on C ═ C bond connection is used for preparing chiral chromatographic stationary phase, a chromatographic column (including high performance liquid chromatography column or gas chromatography capillary column) is prepared for chromatographic separation of racemic compound.
In one embodiment of the present invention, the racemic compound comprises one or more of amino acids, lipids, lactones, amines, alcohols, aldehydes, ketones, olefinic compounds, or chiral drug molecules; chiral drug molecules include warfarin, metoprolol, and pindolol.
As the stationary phase filler for manufacturing the chromatographic column is a C ═ C bond chiral COF material with good physical and chemical stability, the material serving as the chiral stationary phase can be used for chiral separation of liquid chromatography and chiral separation of gas chromatography.
The chiral COF connected by the C-C bond has good stability, can keep the structural integrity under the conditions of strong acid, strong base and high temperature, and completely meets the application in the chromatographic field under different conditions, including normal phase-liquid chromatography, reverse phase-liquid chromatography and gas chromatography. The chiral compound has an open pore channel structure and is rich in chiral action sites, so that a rich host-guest action environment is provided, and the chiral compound is beneficial to interacting with chiral molecules and realizing the separation of racemic compounds.
Due to the difference of the pore channel sizes of the COF-1 or COF-2 obtained by the invention, substrates which can be separated have complementarity, the method has good separation effect on various compounds, and part of the substrates can realize baseline separation.
When used for chromatographic separation of racemic compounds, good separation is achieved for various types of racemic compounds: the separation substrate comprises amino acids, lipids, lactones, amines, alcohols, aldehydes, ketones and olefins; meanwhile, several types of chiral drug molecules with commercial value, including warfarin, metoprolol, pindolol and the like, are well separated.
The chromatographic column is used in chiral separation process, and can realize baseline separation on certain substrates, such as serine, 1- (1-naphthyl) ethanol, alanine, 1, 2-epoxyoctane and the like.
The invention uses a chiral COF connected by a C ═ C bond with excellent physical and chemical stability as a chiral separation material, compounds the COF and silica gel by a 'network packaging method' to obtain a liquid chromatogram chiral stationary phase, and further packs a high performance liquid chromatography column by a high pressure homogenate column packing machine; meanwhile, the chiral capillary gas chromatographic column is prepared by a dynamic coating method. The method widens the design thought of the novel chiral stationary phase, and realizes that a single material simultaneously shows high chiral selectivity in high performance liquid chromatography and high resolution gas chromatography.
Compared with the prior art, the invention has the following characteristics:
1) by utilizing the designability and porosity of the chiral COF, the chiral COF with C ═ C bond connection is synthesized by using a chiral binaphthol skeleton monomer based on crown ether functionalization through a Knoevenagel condensation reaction. The synthesized COF can keep the stability of the structure under the conditions of strong acid, strong base and high temperature, and solves the problem that other chiral stationary phases are unstable under certain conditions;
2) the chiral COF connected with the C-C bond is compounded with silica gel by using a 'network wrapping method', so that a liquid chromatogram chiral stationary phase with uniform particle size is synthesized, and the problems that the stationary phase prepared by directly and mechanically mixing the COF and the silica gel has uneven particle size, causes too high column pressure of a chromatographic column and the like in the existing report are solved;
3) the chiral COF connected by the C-C bond as the stationary phase shows good chiral separation performance in forward-liquid chromatography, reverse-phase-liquid chromatography and gas chromatography, and solves the limitation that other chiral stationary phases can only be used under specific separation conditions;
4) the chiral COF synthesized by the method is rich in chiral crown ether groups, and the aperture sizes of COF-1 and COF-2 are different, so that rich chiral microenvironment is provided, the chiral microenvironment has a good separation effect on various types and sizes of racemic compounds, the effective separation of amino acids, lipids, lactones, amines, alcohols, aldehydes, ketones, olefin compounds and chiral drug molecules is realized, and part of substrates can realize baseline separation.
Drawings
FIG. 1 shows chiral separation data of HPLC in the examples;
FIG. 2 shows chiral separation data of high resolution gas chromatography in the examples;
FIG. 3 is a schematic synthesis of COF in examples;
FIG. 4 is a schematic view of a simulated structure of COF in an embodiment;
FIG. 5 is a schematic flow chart of "packet method" in the embodiment;
FIG. 6 is an electron microscopy characterization of the liquid chromatography chiral stationary phase and the gas capillary column cross-section in an example;
FIG. 7 is a chiral separation chromatogram of a high performance liquid chromatography representative of an example;
FIG. 8 is a high resolution gas chromatography chiral separation chromatogram representative of the examples.
Detailed Description
The invention provides an application of a COF material based on C ═ C bond connection in preparing a chiral chromatographic stationary phase, the COF material based on C ═ C bond connection selects COF-1 or COF-2,
the structural formula of the COF-1 is as follows:
the structural formula of the COF-2 is as follows:
in one embodiment of the present invention, COF materials based on C ═ C bond bonds are prepared by a process comprising: the chiral COF-1 or COF-2 with C ═ C bond connection is synthesized by using a crown ether functionalized binaphthalene tetraaldehyde monomer and terephthalonitrile or 4, 4' -biphenyldiacetonitrile through a Knoevenagel condensation reaction.
The structural formula of the crown ether functionalized bi-binaphthyl tetraaldehyde monomer is as follows:
in one embodiment of the present invention, a method for preparing COF materials based on C ═ C bond linkage, comprises the following steps:
mixing a crown ether functionalized binaphthalene tetracarboxyl monomer, terephthalonitrile or 4, 4' -biphenyl diacetonitrile, dioxane and methanol, heating to a reaction temperature under a vacuum sealing condition, reacting, cooling the mixture to room temperature after the reaction, filtering to obtain a powdery solid, and then washing and drying to obtain COF-1 or COF-2.
In one embodiment of the present invention, one exemplary implementation condition is given based on the method of preparing a COF material in a C ═ C bond connection:
crown ether functionalized bis-naphthaldehyde monomer (30mg, 0.027mmol), terephthalonitrile (8.3mg, 0.053mmol) or 4, 4' -biphenyldiacetonitrile (12.4mg,0.053mmol), dioxane (0.5mL), methanol (0.5mL) were mixed in a 10mL Schlenk tube. The Schlenk tube was vacuum sealed and heated to 120 ℃ for 4 days. The mixture was cooled to room temperature and filtered to give a powdery solid, which was then washed 3 times with deionized water, tetrahydrofuran and diethyl ether, respectively, and dried under vacuum overnight at 60 ℃ to give COF-1 or COF-2.
In one embodiment of the invention, a COF material based on C ═ C bond connection is used for preparing a chiral liquid chromatography stationary phase, and the COF material based on C ═ C bond connection is compounded with silica gel by using a 'network coating method' to prepare the COF chiral stationary phase for high performance liquid chromatography, wherein the COF material based on C ═ C bond connection is selected from COF-1 or COF-2.
In one embodiment of the present invention, the method for preparing COF chiral stationary phase by "net-packing method" is: grinding the COF material based on the C ═ C bond connection to obtain COF powder, then weighing silica gel and suspending the silica gel in a normal hexane solution of 1,3, 5-benzenetricarboxychloride, adding the ground COF powder, and completely evaporating the normal hexane after stirring; preparing an aqueous solution of piperazine, adding the aqueous solution of piperazine into the silica gel treated in the previous step, stirring to ensure that the silica gel is fully contacted with water, soaking, stirring at intervals after soaking is started to ensure that the silica gel is fully contacted with the water, standing to ensure that the silica gel is settled, pouring out the excess aqueous solution, and placing the polymerized silica gel for heat treatment to prepare the chiral stationary phase.
In one embodiment of the present invention, the "screen pack method" for preparing COF chiral stationary phases gives an exemplary implementation condition: the COF material based on C ═ C bond linkage was ground to obtain COF powder with uniform size and smaller particle size, then 3.0g of silica gel was weighed and suspended in a solution of 1,3, 5-benzenetricarboxylic acid chloride in n-hexane (50mL, 0.05mmol), 0.9g of ground COF-1 or COF-2 powder was added, and after stirring for 30 minutes, n-hexane was evaporated to completion. Preparing an aqueous solution of piperazine (50mL, 0.46mol/L), adding the aqueous solution into the silica gel treated in the previous step, stirring to ensure that the silica gel is fully contacted with water, soaking for 2 hours, stirring once every 5min for 15min of beginning soaking to ensure that the silica gel is fully contacted with the water phase, standing to ensure that the silica gel is settled, and finally pouring out the redundant aqueous solution. And (3) placing the polymerized silica gel in an oven at 110 ℃ for heat treatment for 10min to prepare the chiral stationary phase 1 or 2.
In one embodiment of the invention, after the COF material based on the C ═ C bond connection is compounded with silica gel by using a "network packing method" to prepare the COF chiral stationary phase for high performance liquid chromatography, the COF chiral stationary phase for high performance liquid chromatography is packed into a high performance liquid chromatography column by using a high-pressure homogenate column packing machine.
In one embodiment of the present invention, the method for packing the high performance liquid chromatography column by using the high pressure homogenate column packing machine comprises the following steps: placing the prepared COF chiral stationary phase which can be used for high performance liquid chromatography in methanol for suspension, uniformly dispersing silica gel, rapidly pouring the silica gel into a homogenizing tank, taking methanol as a displacement liquid, keeping the methanol at the pressure of 30MPa for 5min, adjusting the pressure to 10-15 MPa, keeping the pressure for 30min, slowly releasing the pressure, and finally installing a sieve plate and a column head of a chromatographic column.
In one embodiment of the present invention, packing of a high performance liquid chromatography column using a high pressure homogenization column packing machine gives an exemplary implementation condition: 3.5g of the chiral stationary phase prepared by the method is weighed, placed in 25mL of methanol for suspension, so that the silica gel is uniformly dispersed and quickly poured into a homogenizing tank. And (3) keeping the methanol as a displacement liquid under the pressure of 30MPa for 5min, adjusting the pressure to 10-15 MPa, keeping the pressure for 30min, and finally slowly releasing the pressure, and finally installing a sieve plate and a column head of the chromatographic column. The size of the high performance liquid chromatography column used was: length: 250 mm; inner diameter: 4.6 mm.
In one embodiment of the invention, a COF material based on C ═ C bond linkage is used for making the chiral gas chromatography stationary phase, and the COF material based on C ═ C bond linkage as the chiral gas chromatography stationary phase can be coated on the tube wall of a gas chromatography column for use.
In one embodiment of the present invention, the COF material based on C ═ C bond connection is used as a chiral gas chromatography stationary phase, and the method for coating on the tube wall of a gas chromatography column is as follows:
weighing COF material powder based on C ═ C bond connection and OV-1701, grinding by using a ball mill, adding ethanol to prepare a suspension, introducing the suspension into an open capillary column under the condition of adding air pressure, pushing the liquid through the capillary column, and leaving a wet coating on the inner wall of the capillary column; a buffer tube is connected to the tail of the capillary column to serve as a flow restrictor, so that the solution is prevented from accelerating in flow rate near the tail end of the column; after the coating was completed, the coated column was flushed with nitrogen, programmed to warm, and finally the column was continuously activated.
In one embodiment of the present invention, the use of the C ═ C bond based COF material as a chiral gas chromatography stationary phase coated on the tube wall of a gas chromatography column gives one exemplary implementation condition:
weighing 3mg COF powder and 6mg OV-1701, grinding with a ball mill, adding 2ml ethanol to make a suspension, introducing the suspension into an open capillary column under added pressure, and pushing the liquid through the capillary column at a rate of 50cm/min, leaving a wet coating on the inner wall of the capillary column. A buffer tube with the length of 2m is connected to the tail of the capillary column to serve as a flow restrictor, so that the solution is prevented from accelerating near the tail end of the column. After the coating was complete, the coated column was flushed with nitrogen for 6h, programmed (1 ℃/min) from 30 ℃ to 300 ℃, and finally the column was activated continuously at 300 ℃ for 3 h. The chromatographic column size is: length: 15 m; inner diameter: 0.25 mm.
In one embodiment of the invention, after the COF material based on C ═ C bond connection is used for preparing chiral chromatographic stationary phase, a chromatographic column (including high performance liquid chromatography column or gas chromatography capillary column) is prepared for chromatographic separation of racemic compound.
In one embodiment of the present invention, the racemic compound comprises one or more of amino acids, lipids, lactones, amines, alcohols, aldehydes, ketones, olefinic compounds, or chiral drug molecules; chiral drug molecules include warfarin, metoprolol, and pindolol.
As the stationary phase filler for manufacturing the chromatographic column is a C ═ C bond chiral COF material with good physical and chemical stability, the material serving as the chiral stationary phase can be used for chiral separation of liquid chromatography and chiral separation of gas chromatography.
The chiral COF connected by the C-C bond has good stability, can keep the structural integrity under the conditions of strong acid, strong base and high temperature, and completely meets the application in the chromatographic field under different conditions, including normal phase-liquid chromatography, reverse phase-liquid chromatography and gas chromatography. The chiral compound has an open pore channel structure and is rich in chiral action sites, so that a rich host-guest action environment is provided, and the chiral compound is beneficial to interacting with chiral molecules and realizing the separation of racemic compounds.
Due to the difference of the pore channel sizes of the COF-1 or COF-2 obtained by the invention, substrates which can be separated have complementarity, the method has good separation effect on various compounds, and part of the substrates can realize baseline separation.
When used for chromatographic separation of racemic compounds, good separation is achieved for various types of racemic compounds: the separation substrate comprises amino acids, lipids, lactones, amines, alcohols, aldehydes, ketones and olefins; meanwhile, several types of chiral drug molecules with commercial value, including warfarin, metoprolol, pindolol and the like, are well separated.
The chromatographic column is used in chiral separation process, and can realize baseline separation on certain substrates, such as serine, 1- (1-naphthyl) ethanol, alanine, 1, 2-epoxyoctane and the like.
The invention uses a chiral COF connected by a C ═ C bond with excellent physical and chemical stability as a chiral separation material, compounds the COF and silica gel by a 'network packaging method' to obtain a liquid chromatogram chiral stationary phase, and further packs a high performance liquid chromatography column by a high pressure homogenate column packing machine; meanwhile, the chiral capillary gas chromatographic column is prepared by a dynamic coating method. The method widens the design thought of the novel chiral stationary phase, and realizes that a single material simultaneously shows high chiral selectivity in high performance liquid chromatography and high resolution gas chromatography.
The invention is described in detail below with reference to the figures and specific embodiments.
Example 1:
preparation of high stability COF-1:
30mg of a crown ether functionalized tetraldehyde monomer having a binaphthyl skeleton, 8.3mg of terephthalonitrile, 0.5mL of dioxane, and 0.5mL of methanol were mixed in a 10mL Schlenk tube. The Schlenk tube was vacuum sealed and heated to 120 ℃ for 4 days. The mixture was cooled to room temperature and filtered to give a powdery solid, which was then washed 3 times with deionized water, tetrahydrofuran and diethyl ether, respectively, and dried under vacuum overnight at 60 ℃ to give 28mg of COF-1 powder as a pale yellow solid.
Example 2:
preparation of high stability COF-2:
30mg of a crown ether-functionalized tetraldehyde monomer having a binaphthyl skeleton, 12.4mg of 4, 4' -biphenyldiacetonitrile, 0.5mL of dioxane, and 0.5mL of methanol were mixed in a 10mL Schlenk tube. The Schlenk tube was vacuum sealed and heated to 120 ℃ for 4 days. The mixture was cooled to room temperature and filtered to give a powdery solid, which was then washed 3 times with deionized water, tetrahydrofuran and diethyl ether, respectively, and dried under vacuum overnight at 60 ℃ to give 29mg of COF-2 as a pale yellow powder.
Example 3:
the method for preparing the liquid chromatogram chiral stationary phase CSP-1 based on COF-1 by the network packaging method comprises the following steps:
grinding the prepared COF-1 to obtain COF powder material with small particle size for later use. 3.0g of silica gel are weighed out and suspended in 50mL of a 0.05mmol solution of 1,3, 5-benzenetricarboxylic acid chloride in n-hexane, 0.9g of ground COF-1 powder are subsequently added, and after stirring for 30 minutes the n-hexane is evaporated to completion. Preparing 50ml of 0.46mol/L piperazine aqueous solution, adding the aqueous solution into the treated silica gel, soaking for 2 hours to enable the surface of the silica gel to generate interfacial polymerization reaction, stirring once every 5min within the first 15min of just beginning soaking, then standing to enable the silica gel to settle, and finally pouring out the excess aqueous solution. And (3) placing the polymerized silica gel in an oven at 110 ℃ for heat treatment for 10min to prepare the chiral stationary phase 1 (CSP-1).
Example 4:
the method for preparing the liquid chromatogram chiral stationary phase CSP-2 based on COF-2 by the network packaging method comprises the following steps:
and grinding the prepared COF-2 to obtain a COF powder material with small particle size for later use. 3.0g of silica gel are weighed out and suspended in 50mL of a 0.05mmol solution of 1,3, 5-benzenetricarboxylic acid chloride in n-hexane, 0.9g of ground COF-2 powder are subsequently added, and after stirring for 30 minutes the n-hexane is evaporated to completion. Preparing 50ml of 0.46mol/L piperazine aqueous solution, adding the aqueous solution into the treated silica gel, soaking for 2 hours to enable the surface of the silica gel to generate interfacial polymerization reaction, stirring once every 5min within the first 15min of just beginning soaking, then standing to enable the silica gel to settle, and finally pouring out the excess aqueous solution. And (3) placing the polymerized silica gel in an oven at 110 ℃ for heat treatment for 10min to prepare the chiral stationary phase 1 (CSP-2).
Example 5:
adopting a high-pressure homogenate column filling machine to fill a COF-1 high performance liquid chromatography column:
3.5g CSP-1 was weighed, suspended in 25mL methanol, allowed to disperse uniformly over silica gel and poured quickly into a homogenization tank. A stainless steel column having a length of 250mm and an inner diameter of 4.6mm was attached to the lower part of the homogenizing tube, followed by pressure-packing with a high-pressure homogenizing-packing machine. And (3) keeping the methanol as a displacement liquid under the pressure of 30MPa for 5min, adjusting the pressure to 10-15 MPa, keeping the pressure for 30min, slowly releasing the pressure, and finally installing a sieve plate and a column head of the chromatographic column to prepare the COF-1-based high performance liquid chromatographic column.
Example 6:
adopting a high-pressure homogenate column filling machine to fill a COF-2 high-performance liquid chromatography column:
3.5g CSP-2 was weighed, suspended in 25mL methanol, allowed to disperse uniformly over silica gel and poured quickly into a homogenization tank. A stainless steel column having a length of 250mm and an inner diameter of 4.6mm was attached to the lower part of the homogenizing tube, followed by pressure-packing with a high-pressure homogenizing-packing machine. And (3) keeping the methanol as a displacement liquid under the pressure of 30MPa for 5min, adjusting the pressure to 10-15 MPa, keeping the pressure for 30min, slowly releasing the pressure, and finally installing a sieve plate and a column head of the chromatographic column to prepare the COF-2-based high performance liquid chromatographic column.
Example 7:
preparing a COF-1 capillary gas chromatographic column by a dynamic coating method:
after 3mg of COF-1 powder and 6mg of OV-1701 powder were weighed and ground by means of a ball mill, 2ml of ethanol was added to prepare a suspension, the suspension was pressed under an atmospheric pressure into a capillary column having a length of 15m and an inner diameter of 0.25mm, and the dispersion was pushed through the capillary column at a uniform velocity at a flow rate of 50cm/min, thereby leaving a uniform wet coating on the inner wall of the capillary column. In addition, a 2m long buffer tube is required to be attached to the end of the capillary column as a flow restrictor to avoid the plug of solution accelerating near the end of the column. After the coating was complete, the coated column was flushed with nitrogen for 6h and finally the column was activated continuously at 300 ℃ for 3 h.
Example 8:
preparing a COF-2 capillary gas chromatographic column by a dynamic coating method:
after 3mg of COF-2 powder and 6mg of OV-1701 powder were weighed and ground by means of a ball mill, 2ml of ethanol was added to prepare a suspension, the suspension was pressed under an atmospheric pressure into a capillary column having a length of 15m and an inner diameter of 0.25mm, and the dispersion was pushed through the capillary column at a constant velocity at a flow rate of 50cm/min, thereby leaving a uniform wet coating on the inner wall of the capillary column. In addition, a 2m long buffer tube is required to be attached to the end of the capillary column as a flow restrictor to avoid the plug of solution accelerating near the end of the column. After the coating was complete, the coated column was flushed with nitrogen for 6h and finally the column was activated continuously at 300 ℃ for 3 h.
The chiral separation performance of the high performance liquid chromatography column prepared in the above example was tested by the following method:
(1) the chiral separation performance of the HPLC column prepared in the above example was tested by selecting racemic compounds of threonine, phenylalanine, alanine, serine, aspartic acid, glutamic acid, phenylglycine, methionine, histidine, arginine, isoleucine, 3, 5-dinitro-N- (1-phenylethyl) -benzamide, 1- (1-naphthyl) ethanol, 3-buten-2-ol, β -butyrolactone, isopropyl glycidyl ether, ethyl lactate, 1, 2-epoxyoctane, methylphenylsulfoxide, 2-phenylpropanol, propranolol hydrochloride, clenbuterol, pindolol, mexiletine hydrochloride, warfarin, and metoprolol.
FIG. 1 is the results of the test and identifies the liquid chromatography conditions and UV detector wavelength: mobile phase: a MeOH/H2O(9:1，v/v)，b:MeOH/H2O (8:2, v/v), c: n-hexane/isopropanol (9:1, v/v). Flow rate: 0.5 ml/min. Temperature: at 25 ℃.
The chiral separation performance of the capillary gas chromatography column prepared in the above example was tested by the following method:
(1) chiral separation performance of the capillary gas chromatography column prepared in the above example was tested using a racemic compound of threonine, glutamic acid, serine, isoleucine, leucine, phenylglycine, cysteine, arginine, valine, phenylalanine, β -butyrolactone, 3-buten-2-ol, 1, 3-butanediol, 2-methylpentanoic acid methyl ester, 2-chloropropionic acid methyl ester, γ -octanoic acid lactone, 2-methylhexanoic acid, citral, ethyl lactate, 2-chlorocyclohexanone, 2-methylpentanal, 2-methyltetrahydrofuran-3-one, 1, 2-propylene oxide, nerol, geraniol, 1-phenylethylamine and limonene.
FIG. 2 shows the results of the test and indicates the gas chromatography conditions (column temperature and gas flow rate).
In order to comprehensively evaluate the separation performance of the prepared chromatographic column on enantiomers, the separation efficiency of the chromatographic column is evaluated by using two parameters, namely a separation factor (alpha) and a separation degree (Rs). The separation factor (α) and the degree of separation (Rs) are calculated by the following formulas:
α＝tR2/tR1
Rs＝2(tR2-tR1)/(W2+W1)
wherein t isR2And tR1Retention times (t) for the R enantiomer and the S enantiomer, respectivelyR2>tR1)；W2And W1Peak widths at baseline (W) for the two enantiomers respectively2>W1)。
FIG. 3 is a schematic diagram of the synthesis of COF-1 and COF-2, and chiral COF-1 or COF-2 with C ═ C bond is synthesized by Knoevenagel condensation reaction of chiral binaphthol skeleton monomer based on crown ether functionalization and terephthalonitrile or 4, 4' -biphenyl diacetonitrile.
FIG. 4 is a schematic diagram of the simulated structure of COF-1 and COF-2, which form a layered network structure in two dimensions, and the layers are stacked through pi-pi action, and finally form quadrilateral pore channels in one dimension.
FIG. 5 is a schematic flow chart of the preparation of chiral stationary phase by the "net-pack method". Weighing silica gel beads, suspending the silica gel beads in a n-hexane solution of trimesoyl chloride, adding the ground COF, stirring, and completely evaporating the n-hexane to obtain the COF and the silica gel beads wrapped by the trimesoyl chloride. And adding the aqueous solution of piperazine into silica gel to obtain silica gel beads wrapped by the aqueous solution of piperazine. And then, carrying out interfacial polymerization reaction on the boundary of the silica gel surface and the aqueous solution, thereby preparing the chiral stationary phase.
FIG. 6 is a scanning electron micrograph of a liquid chromatography stationary phase and a cross section of a capillary column. Fig. 6a and 6b are scanning electron microscope photographs of a COF-based liquid chromatography stationary phase prepared by a "mesh-coating method", which show that the surface of silica gel is coated by a polymer network; fig. 6c and 6d are scanning electron micrographs of a cross-section of a COF based capillary column prepared by the kinetic coating method, and it can be seen that the inner surface of the capillary column is uniformly coated with a COF layer.
FIG. 7 is a chiral separation chromatogram of a representative high performance liquid chromatography, and it can be seen that a column packed on the basis of a COF-1 stationary phase can achieve baseline separation of racemic compounds of serine and 1- (1-naphthyl) ethanol; chromatographic columns packed on a COF-2 stationary phase enable baseline separation of racemic compounds of alanine and 1, 2-epoxyoctane.
FIG. 8 is a chiral separation chromatogram of a representative high resolution gas chromatograph, and it can be seen that a column based on COF-1 coating can separate racemic compounds of glutamic acid and ethyl lactate; the resulting column, coated on the basis of COF-2, enables the separation of racemic compounds capable of reacting to phenylalanine and 2-methylpentanal.
Example 9:
a preparation method and application of a chiral chromatographic stationary phase based on COF connected by C ═ C bonds comprises the following steps:
1) synthesizing a chiral COF (COF) with a C-bond connection based on a Knoevenagel condensation reaction by using a crown ether functionalized bigeminal naphthalene tetraaldehyde monomer;
2) compounding the COF and silica gel by using a 'network wrapping method' to prepare a high performance liquid chromatography chiral stationary phase, and filling the COF into a high performance liquid chromatography column by using a high-pressure homogenate column filling machine;
3) uniformly coating COF on the tube wall of a gas chromatography capillary column by using a dynamic coating method;
4) the high performance liquid chromatography column and the gas chromatography capillary column prepared above are used for chromatographic separation of racemic compounds.
In step 1), a crown ether-functionalized tetraldehyde monomer of a binaphthyl skeleton (60mg, 0.05mmol), terephthalonitrile (16.6mg, 0.1mmol) or 4, 4' -biphenyldiacetonitrile (24.8mg,0.1mmol), dioxane (1.0mL), and methanol (1.0mL) were mixed in a 10mL Schlenk tube. The Schlenk tube was vacuum sealed and heated to 120 ℃ for 7 days. The mixture was cooled to room temperature and filtered to give a powdery solid, which was then washed 3 times with deionized water, tetrahydrofuran and diethyl ether, respectively, and dried under vacuum at 60 ℃ overnight.
In the step 2), preparing a COF chiral stationary phase by using a 'network wrapping method': and grinding the prepared COF powder to obtain the COF material with small particle size. Subsequently, 6.0g of silica gel was suspended in a solution of 1,3, 5-benzenetricarboxylic acid chloride in n-hexane (100mL, 0.05mmol), 1.8g of ground COF powder was added, and after stirring for 30 minutes, the n-hexane was evaporated to completion. Preparing an aqueous solution of piperazine (100mL, 0.46mol/L), adding the aqueous solution into the silica gel treated in the previous step, stirring to ensure that the silica gel is fully contacted with water, soaking for 2 hours, stirring once every 3min for 15min of beginning soaking to ensure that the silica gel is fully contacted with the water phase, standing to ensure that the silica gel is settled, and finally pouring out the redundant aqueous solution. And (3) placing the polymerized silica gel in an oven at 100 ℃ for heat treatment for 20min to prepare the chiral stationary phase. Then, a high-pressure homogenizing column filling machine is used for filling the high-performance liquid chromatography column: 3.5g of the chiral stationary phase prepared by the method is weighed, placed in 25mL of methanol for suspension, so that the silica gel is uniformly dispersed and quickly poured into a homogenizing tank. And (3) keeping the methanol as a displacement liquid under the pressure of 30MPa for 5min, adjusting the pressure to 10-15 MPa, keeping the pressure for 30min, and finally slowly releasing the pressure, and finally installing a sieve plate and a column head of the chromatographic column. The size of the high performance liquid chromatography column used was: length: 250 mm; inner diameter: 4.6 mm.
In step 3), preparing a chiral gas chromatography capillary column by using a dynamic coating method: weighing 6mg COF powder and 12mg OV-1701, milling with a ball mill, adding 4ml ethanol to make a suspension, introducing the suspension into an open capillary column under added pressure, and pushing the liquid through the capillary column at a rate of 50cm/min, leaving a wet coating on the inner wall of the capillary column. A2 m long buffer tube is connected to the tail of the capillary column to serve as a flow restrictor, so that the solution plug is prevented from accelerating near the column end. After the coating was complete, the coated column was flushed with nitrogen for 6h, programmed (1 ℃/min) from 30 ℃ to 280 ℃, and finally the column was activated continuously at 280 ℃ for 3 h. The capillary gas chromatography column sizes used were: length: 15 m; inner diameter: 0.25 mm.
The prepared high performance liquid chromatography column is used for separating racemic compounds under a normal phase chromatography system and a reverse phase chromatography system, and the gas chromatography capillary column is used for separating the racemic compounds under the condition that gas is used as a mobile phase. The effective separation of amino acid, lipid, lactone, amine, alcohol, aldehyde, ketone, olefin compounds and chiral drug molecules is realized, and the base line separation of partial substrates can be realized.
Example 10:
a preparation method and application of a chiral chromatographic stationary phase based on COF connected by C ═ C bonds comprises the following steps:
1) synthesizing a chiral COF (COF) with a C-bond connection based on a Knoevenagel condensation reaction by using a crown ether functionalized bigeminal naphthalene tetraaldehyde monomer;
2) compounding the COF and silica gel by using a 'network wrapping method' to prepare a high performance liquid chromatography chiral stationary phase, and filling the COF into a high performance liquid chromatography column by using a high-pressure homogenate column filling machine;
3) uniformly coating COF on the tube wall of a gas chromatography capillary column by using a dynamic coating method;
4) the high performance liquid chromatography column and the gas chromatography capillary column prepared above are used for chromatographic separation of racemic compounds.
In step 1), a crown ether-functionalized tetraldehyde monomer of a binaphthyl skeleton (30mg, 0.027mmol), terephthalonitrile (8.3mg, 0.053mmol) or 4, 4' -biphenyldiacetonitrile (12.4mg,0.053mmol), dioxane (0.5mL), methanol (0.5mL) were mixed in a 10mL Schlenk tube. The Schlenk tube was vacuum sealed and heated to 115 ℃ for 5 days. The mixture was cooled to room temperature and filtered to give a powdery solid, which was then washed 3 times with deionized water, tetrahydrofuran and diethyl ether, respectively, and dried under vacuum at 60 ℃ overnight.
In the step 2), preparing a COF chiral stationary phase by using a 'network wrapping method': and grinding the prepared COF powder to obtain the COF material with small particle size. Subsequently, 3.0g of silica gel were weighed out and suspended in a solution of 1,3, 5-benzenetricarboxylic acid chloride in n-hexane (50mL, 0.05mmol), 0.9g of ground COF powder was added, and after stirring for 30 minutes, the n-hexane was evaporated to completion. Preparing an aqueous solution of piperazine (50mL, 0.46mol/L), adding the aqueous solution into the silica gel treated in the previous step, stirring to ensure that the silica gel is fully contacted with water, soaking for 2 hours, stirring once every 4min for 16 min after soaking is started to ensure that the silica gel is fully contacted with the water phase, standing to ensure that the silica gel is settled, and finally pouring out the redundant aqueous solution. And (3) placing the polymerized silica gel in an oven at 115 ℃ for heat treatment for 10min to prepare the chiral stationary phase. Then, a high-pressure homogenizing column filling machine is used for filling the high-performance liquid chromatography column: 4.0g of the chiral stationary phase prepared by the method is weighed and placed in 25mL of a mixed solution (9:1, v/v) of n-hexane and isopropanol to be suspended, so that silica gel is uniformly dispersed and is quickly poured into a homogenizing tank. And (3) taking a mixed solution (9:1, v/v) of normal hexane and isopropanol as a displacement solution, keeping for 10min under the pressure of 35MPa, adjusting the pressure to 10-15 MPa, keeping for 1h, and finally slowly releasing pressure, and finally installing a sieve plate and a column head of the chromatographic column. The size of the high performance liquid chromatography column used was: length: 250 mm; inner diameter: 4.6 mm.
In step 3), preparing a chiral gas chromatography capillary column by using a dynamic coating method: weighing 5mg COF powder and 10mg OV-1701, milling with a ball mill, adding 3.5ml ethanol to make a suspension, introducing the suspension into an open capillary column under added pressure, and pushing the liquid through the capillary column at a rate of 50cm/min, leaving a wet coating on the inner wall of the capillary column. A2 m long buffer tube is connected to the tail of the capillary column to serve as a flow restrictor, so that the solution plug is prevented from accelerating near the column end. After the coating was complete, the coated column was flushed with nitrogen for 5h, programmed (1 ℃/min) from 25 ℃ to 250 ℃, and finally the column was continuously activated at 250 ℃ for 5 h. The capillary gas chromatography column sizes used were: length: 15 m; inner diameter: 0.25 mm.
The prepared high performance liquid chromatography column is used for separating racemic compounds under a normal phase chromatography system and a reverse phase chromatography system, and the gas chromatography capillary column is used for separating the racemic compounds under the condition that gas is used as a mobile phase. The effective separation of amino acid, lipid, lactone, amine, alcohol, aldehyde, ketone, olefin compounds and chiral drug molecules is realized, and the base line separation of partial substrates can be realized.
The embodiments described above are described to facilitate an understanding and use of the invention by those skilled in the art. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above embodiments, and those skilled in the art should make improvements and modifications within the scope of the present invention based on the disclosure of the present invention.
- 上一篇：一种医用注射器针头装配设备
- 下一篇：一种饱和活性炭活化再生处理工艺及控制方法