Conformational transition effects of anion recognition by calix[4]arene derivatives

Abstract

A calix[4]arene derivative (3) possessing naphthalene sulfonyl amide groups has been synthesised in satisfactory yield. Furthermore, its conformation and anion-binding behaviours are systemically investigated by the methods of fluorescence spectrometry, ¹H NMR spectrometry and X-ray crystallography. The results indicate that compound 3 assumes two different configurations in polar/apolar solutions, and therefore presents the interestingly solvent-dependent binding properties for anions. It is demonstrated that hydrogen-bonding interactions do play a great role in the conformation of 3 and its anion recognition.

Keywords:

• calixarene
• fluorescence spectroscopy
• anionic recognition

Acknowledgements

This work was supported by the 973 Program (2006CB932900), NNSFC (Nos. 20421202, 20673061 and 20703025) and 111Project (No. B06005), which are gratefully acknowledged. We also thank Dr Heather Spangler at the Department of Chemistry in the Iowa State University for the assistance in the preparation of this manuscript.