Application of diazacrown ethers as a stationary liquid phase in chromatography

Abstract

Development and practical application of chemical analysis methods in our time is one of the pressing problems in all areas of science. Schiff macrocycle containing many analytically active and functional groups Dibenzo-diazacrown ethers are important in the practice of analytical chemistry. Accessible synthesis of this type of crown ethers for the development and implementation of analytical methods very important. Nitrogen groups contained in dibenzo-diazacrown ethers with a complexing agent permanent donor-acceptor, creates a covalent bond with OH- groups. high level of ionic protection Due to their selectivity and sensitivity to Me+ ions, dibenzo-diazacrown ethers as organic ligands widely used in analytical chemical practice. In our research work, by blocking bisphenols with a trans conformation, 1,4-dibromobutene-2 disubstituted macrocyclic dibenzo-diazocrown ethers (Schiff bases) and their chemical composition. their significance was studied by chemical analysis. Purity of the resulting macrocyclic Schiff bases studied by chromatographic methods of analysis, and their structure was confirmed on the basis of IR and NMR spectra, action spectra were studied.

These crown ethers are subjected to gas-liquid chromatography of chlorinated hydrocarbons (allyl chloride) and were tested in the form of a stationary liquid phase by GLC chromatography, the composition was determined micrograms of chlorinated hydrocarbons. It was found that the separation coefficient of the synthesized crown ethers is 1.5-2 times higher than that of previously used traditional adsorbents in gas-liquid chromatography. Another property of macrocyclic Schiff compounds is that they convert you can switch from sis- form trans- and vice versa. Using this property, Ag+ ion can be condensed from solutions by chromatographic method. To this end, Schiff-based macrocyclic compounds impregnated the surface with ASK brand silica gel, adsorbent length 1 m, diameter 1 cm. They poured it into a quartz glass column.