Effects of pressure on inclusion complexation of methylene blue with water-soluble p-sulfonatocalix[n]arenes

Yoshimi Sueishi, Naoya Inazumi, Tadashi Hanaya

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19 Citations (Scopus)


The effects of pressure were examined for the inclusion complexation of water-soluble p-sulfonated calix[n]arenes (Calix-Sn: n = 4, Calix-S4; n = 6, Calix-S6; n = 8, Calix-S8) with methylene blue (MB). A differential pressure effect was found in the inclusion equilibria of Calix-Sn. As the external pressure increases, the inclusion equilibrium of MB with Calix-S4 and Calix-S6 shifts to the dissociation side. However, with Calix-S8, the inclusion equilibrium shifts to the association side with increased pressure. From the pressure dependence of the inclusion equilibria of Calix-Sn, the reaction volumes, which are changes in volume accompanied by inclusion, were estimated as 32.1 cm3 mol-1 for Calix-S4, 30.1 cm3 mol-1 for Calix-S6 and - 13.8 cm3 mol-1 for Calix-S8. In addition, the structures of the inclusion complexes of Calix-Sn with MB have been established by 1H NMR measurements. Based on the results, the behavior of inclusion complexation with Calix-Sn is discussed.

Original languageEnglish
Pages (from-to)448-455
Number of pages8
JournalJournal of Physical Organic Chemistry
Issue number5
Publication statusPublished - May 2005


  • Calixarene
  • Inclusion complexation
  • NMR
  • Pressure effect

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Organic Chemistry


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