| Since the compound Ferrocene was firstly synthesized and isolated by Kealy and Pauson, its metal sandwich structure was completely determined. Two cyclopentadienyl ligands in ferrocene molecule combines with iron by covalent bond, and the two carbon rings have π electronic aromaticity and hydrophobic selectivity. Over half a century, these features make ferrocene ligands with research potential and good application prospects in organometallic chemistry, materials science, industrial application and so on, especially in catalytic fields. In addition to the application in catalysis, Ferrocene as probes of electrochemical modification in analytical chemistry has been widely used in recent years. However, such organometallic bonded stationary phase as a new type of chromatographic separation media, the studies are still in its infancy aspects. There are still few reports concerning such stationary phase in chromatography analysis. Therefore, we will develope new ferrocene-bonded stationary phase and expand the application of ferrocene ligand based on our research basis.The Pirkle type stationary phase(SP) is a kind of important phase with a widely application, a large usage, and deeply revealing recognition mechanism. At present, the researches in column packing and separation mechanism of new Pirkle type CSP are the focuses in HPLC. Therefore, in this paper, two new silica-bonded stationary phases with ferrocene as skeleton material were synthesized. Also, its chromatographic behaviors were studied. The main contents are as following:1、A new Pirkle type silica-bonded N-ferrocenyl(benzoyl)amino-acid esters stationary phase was synthesized and characterized by infrared spectroscopy, elemental analysis and thermogravimetricanalysis. We used different solute probes including Amines, phenols, polycyclic aromatic hydrocarbons(PAHs) and so on to study the chromatographic behaviors of the new stationary phase. Due to the special nature of ferrocene molecule, the chromatographic performance and retention mechanism of the new phase were evaluated in reversed-phase(RP) and normal-phase(NP) modes. The results showed that this new phase could also provide various action sites for different solutes, such as hydrophobic, hydrogenbonding, dipole–dipole interactions, π electron transfer, charge-transfer and acid-base equilibrium interactions. Because of the chiral carbon atom in the stationary phase, it provides possibility to separate some specific chiral compound. In this paper, we tried to separate Lansoprazole enantiomer.2、The new Pirkle type silica-bonded N-ferrocenyl(benzoyl)amino-acid esters stationary phase was successfully employed for the analysis of organophosphorus pesticide residue in vegetable samples. The results were satisfactory with good linearity(r2 > 0.999), low detection limit(phoxim 20 ng/m L, pyrazophos 30 ng/m L, parathion-methyl 30 ng/m L), good reproducibility(RSD < 0.16%) and high recovery(phoxim 82.9%-99.7%, pyrazophos 90.6%-103.4%, parathion-methyl 93.5%-101.2%).3 、 The silica-bonded(4-cyclopentadienyl benzoic acid-iron-toluene) hexafluorophosphoric acid stationary phase was prepared.The structure of new material was characterized by infrared spectroscopy, elemental analysis and thermogravimetric analysis and so on. The chromatographic performance and retention mechanism of ferrocene phase were evaluated using different solute probes including polycyclic aromatic hydrocarbons(PAHs), positional isomers of naphthylamine, nitraniline, nitroimidazole, organophosphorus and so on. The results showed that this new phase possess obvious normal-phase chromatographic performance, it could provide various action sites for different solutes in normal-phase(NP), such as π electron transfer, π-π electron, dipole-dipole, and electrostatic interactions with the substrates. Also the possible separation mechanisms were discussed. |
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