Anion binding can be achieved by neutral receptors through hydrogen bonding or by positively charged ligands through electrostatic interaction.¹ Some examples of both types of receptors based on calixarene structures have already been published.²
We report here the synthesis of two new positively charged calix[4]arene derivatives substituted at the lower rim by two and four triphenylphosphonium butyl groups, respectively. The first results of UV and NMR experiments concerning their ability to complex tetrahedral oxyanions (ClO₄ ^-) and iodide will also be presented.

References
1. P. D. Beer and P. A. Gale, Angew. Chem. Int. Ed. Engl. 2001, 40, 486.
2. S. E. Matthews, P. D. Beer, in "Calixarenes 2001", Z. Asfari, V. Bohmer, J. Harrowfield, J. Vicens Eds., Kluwer Academic Publishers, Dordrecht, 2001, p. 421-439.

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/1241 must be provided.