Abstract
A convenient method for the preparation of biscalix[4]arenes was established. Using the system of acetonitrile-potassium carbonate sealed in a Schlenk tube at 100 °C allows facile syntheses of symmetric biscalix[4]arenes and 25,27-dibromoalkyl calix[4]arene. The latter can be tethered by another equivalent of calix[4]arene to furnish an unsymmetric biscalix[4]arene that exhibits superior selectivity for cesium.
Keywords
biscalix[4]arene - calix[4]semitube - selectivity - cesium ion
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