Macrocyclic π-Conjugated Carbopolyanions and Polyradicals Based upon Calix[4]arene and Calix[3]arene Rings

Andrzej Rajca, Suchada Rajca, Shailesh R. Desai

Research output: Contribution to journalArticle

81 Scopus citations

Abstract

Calix[4]arene- and calix[3]arene-based polyether precursors to polyradicals are synthesized. π-Conjugated carbanions, such as calix[4]arene-based tetraanion and calix[3]arene-based trianion, are prepared and studied using NMR spectroscopy and voltammetry. A 4-fold-symmetric conformer for the tetraanion and two non-interconverting conformers (3-fold- and 2-fold-symmetric) for the trianion are found on the NMR time scale. Oxidation of the tetraanion gives the corresponding calix[4]arene-based S = 2 tetraradical. However, ESR spectroscopy suggests that the predominant product from oxidation of calix[3]arene-based trianion is the corresponding triradical dimer. The related calix[3]arene-based S = 1 diradical is found to be monomeric. Additional characterization of octaradical 18. and pentaradical 25., which were described in a preliminary communication, is presented.

Original languageEnglish (US)
Pages (from-to)806-816
Number of pages11
JournalJournal of the American Chemical Society
Volume117
Issue number2
DOIs
StatePublished - Jan 1995

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ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry

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