New diamino derivatives of p-tert-butylcalix[4]arene for oxyanion recognition: synthesis and complexation studies

Abstract

We have prepared new diamino derivatives of p-tert-butylcalix[4]arene from the reduction of corresponding amide derivatives. The examination of their recognition abilities towards some selected oxyanions shows that the new calix[4]arene amines are mostly more effective receptors than their amide derivatives for dichromate anions and nitrite, and capable of extracting these anions in yields as high as 95%. However, neither the calix[4]arene amines nor their corresponding amides were capable of extracting phosphate or nitrate at pH 1.5.

Keywords:

• calix[4]arene
• diamines
• oxyanions
• complexation
• extraction

Acknowledgements

We thank the Scientific and Technical Research Council of Turkey (TUBITAK-Grant Number TBAG-104T199) and Research Foundation of Selçuk University, Konya, Turkey for their financial support to this work.