Synthesis, structure and anion binding properties of lower rim α-hydroxyamide calix[4]arene derivatives

A new family of p-tert-butylcalix[4]arenes functionalized at the lower rim with α-ketoamide or α-hydroxyamide functions has been prepared. Host-guest complexation properties towards various anions of a chiral α-hydroxyamide have been examined by 1H NMR spectroscopy. This new receptor has shown promising selectivity for H2PO4- and N-tosyl-(L)-alaninate.