The syntheses of two polymer supported calix[4]arenes 8 and 9, using TentaG
el S NH21 and aminomethyl polystyrene, have been significantly improved by
the replacement of thionyl chloride and excessive amounts of solvents with
carbodiimide coupling reagents. The new, environmentally friendly route red
uces the number of synthetic steps from five to three and achieves a high l
oading of calix[4]arene, as shown by attenuated total reflectance infrared
spectroscopy (ATR-IR), NMR and solid-state NMR. Furthermore, the extraction
efficiencies of uranium and cadmium by these polymer supported calix[4]are
nes demonstrate an additional green aspect to the work.