Expedient Immobilization of TEMPO by Copper-Catalyzed Azide-Alkyne [3+2]-Cycloaddition onto Polystyrene Resin

Abstract

TEMPO was readily grafted by copper(I)-catalyzed azide-alkyne cycloaddition onto polystyrene. Starting with commercially available Merrifield resin (4.3 mmol/ g) almost quantitative loading of TEMPO onto the polymer was achieved (≥4 mmol/ g). The so obtained PS-CLICK-TEMPO allowed the oxidation of alcohols to aldehydes with bleach or molecular oxygen as the terminal oxidant with high yields and selectivity in multiple cycles without loss of activity.