English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Using the inclusion complexation of methylene blue with  p -sulfonatocalix[6]arene (Calix-S6) as a chemical indicator, the association constants of inclusion complexes of Calix-S6 with visible-spectroscopically inert 1-butyl-3-methylimidazolium salts (ionic liquids (IL): counter anions BF 4   –  , PF 6   –  , and Cl  –  ) were determined. It was found that the experimentally observed association constants of IL with Calix-S6 in a water-methanol mixture increased in the order of counter anion Cl  –   &lt; BF 4   –   &lt; PF 6   –  . The  19 F NMR signals of counter anions BF 4   –   and PF 6   –   shift upfield upon addition of Calix-S6. From the  19 F NMR chemical shifts, we suggested that Calix-S6 forms weak 1:1 complexes with the BF 4   –   and PF 6   –   anions. The binding constants and their thermodynamic parameters for the complexation of the BF 4   –   and PF 6   –   anions with Calix-S6 were evaluated in a water-methanol mixture (6:4 ( V / V )) at 298 K:  K  A  = 26.2 M  – 1  for BF 4   –   and 106 M  – 1  for PF 6   –  . Based on the results, the characteristics for the complexation of the counter anions with Calix-S6 were discussed and the inclusion constants of Calix-S6 with the cationic ring moiety of 1-butyl-3-methyl-imidazolium salts were determined.

Influence of Counter Anions on Inclusion Complexation of p -Sulfonatocalix[6]arene with 1-Butyl-3-methylimidazolium Salts (Ionic Liquids)