Head-to-Tail Connected Double Calix[4]arenes

Article abstract of DOI:10.1007/BF00807096

New macrotricyclic compounds consisting of two calix[4]arene substructures connected by aliphatic chains of various length (three to five carbon atoms) between two opposite p-positions and two distal phenolic oxygens have been synthesized. Starting with p-tert-butyl-calix[4]arene, two O-protected phenolic units are attached via ether links in 1,3-position by reaction with the corresponding tosylates. After deprotection, the new calix[4]arene is formed by fragment condensation with 2,6-tobromomethylated 4-alkylphenols. The structure of one example (8c) has been confirmed by single crystal X-ray analysis. Both calixarene parts assume the cone conformation, a molecule of acetonitrile being included in both cavities.