title: Efficient fragment coupling approaches toward large oxacalix[n]arenes (n = 6, 8).
abstract: The first rational, stepwise synthesis of enlarged oxacalix[n]arenes (n > 4) is described. Variously substituted oxacalix[3]arene[3]pyrimidines were prepared rather selectively by a straightforward [3 + 3] fragment coupling approach after a thorough search for the optimum nucleophilic aromatic substitution conditions. Similar procedures also allowed facile synthesis of unsymmetrical oxacalix[4]- and oxacalix[8]arenes.
authors.affiliation: Molecular Design and Synthesis, Department of Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium.
authors.forename: Wim
authors.initials: W
authors.lastname: Van Rossom
authors.forename: Margriet
authors.initials: M
authors.lastname: Ovaere
authors.forename: Luc
authors.initials: L
authors.lastname: Van Meervelt
authors.forename: Wim
authors.initials: W
authors.lastname: Dehaen
authors.forename: Wouter
authors.initials: W
authors.lastname: Maes