title: Narrow-rim functionalization of calix[4]arenes via Sonogashira coupling reactions.
abstract: The narrow (or "lower")-rim hydroxyl groups of calixarenes are known to be resistant to substitution/displacement. The Sonogashira coupling reaction with TMSA and phenylacetylene, however, has now been extended to the bistriflate of p-tert-butylcalix[4]arene, previously known to be resistant to Stille, Neigishi, or Suzuki-Miyaura reactions. Under some of the reaction conditions investigated, the previously unknown narrow-rim mono- and diiodo-p-tert-butylcalix[4]arene products were also produced, in addition to the narrow-rim mono- and dialkynyl products. Homocoupling of the narrow-rim monoethynyl-p-tert-butyl-calix[4]arene produced a new narrow-rim rigid butadiyne-linked bis-p-tert-butylcalix[4]arene.
authors.affiliation: Department of Chemistry, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador A1B 3X7, Canada.
authors.forename: Hassan
authors.initials: H
authors.lastname: Al-Saraierh
authors.forename: David O
authors.initials: DO
authors.lastname: Miller
authors.forename: Paris E
authors.initials: PE
authors.lastname: Georghiou