Highly Sodium-Selective Fluoroionophore Based on Conformational Restriction of Oligoethyleneglycol-Bridged Biaryl Boron−Dipyrromethene

Abstract
A non-PET and non-PCT fluoroionophore has been designed and synthesized based on the combination of a biaryl boron−dipyrromethene fluorophore with an oligoethyleneglycol bridge. A specific red-shift response of absorption for NaClO4 in acetonitrile was demonstrated based on conformational restriction triggered by cation recognition at the bridge. The concentration of Na+ can be determined accurately using fluorescence due to a high extinction coefficient (ε = 50 000), a high fluorescence quantum yield (Φf = 0.68), and the sharpness of absorption and emission peaks of the boron−dipyrromethene derivative.