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Calix Crowns Derived from para-Bridged Calix
1Institut für Anorganische Chemie der Technischen Universität, Mommsenstrasse 13, D-01062 Dresden, Germany, Hoechst Marion Roussel, D-65926 Frankfurt/Main, Germany, and Fachbereich Chemie und Pharmazie, Abteilung Lehramt Chemie, Johannes Gutenberg-Universität, Duesbergweg 10-14, D-55099 Mainz, Germany.
Abstract:
Two calix[4]arenes, bridged by aliphatic chains of five and eight carbon atoms spanning two opposite para positions, have been converted into their 1,3-crown ether derivatives by reaction with tetraethylene and pentaethylene glycol ditosylates. Of the two possible 1,3-crown derivatives, only the formation of those isomers is observed in which the phenolic units connected at the para positions are etherified. This has been established in one case by a single-crystal X-ray analysis. Preliminary results for the extraction of selected alkali and alkaline-earth metals are reported.
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