A fluorescent chemosensor based on optically active 2,2′‐binaphtho‐20‐crown‐6 for metal ions

Abstract

A chiral conjugated polymer can be obtained by the polymerization of (S)‐6,6′‐dibromo‐2,2′‐binaphtho‐20‐crown‐6 and 1,4‐divinyl‐2,5‐dibutoxybenzene via a palladium‐catalyzed Heck cross‐coupling reaction. The chiral conjugated polymer shows strong green‐blue fluorescence. The responsive properties of the chiral polymer to metal ions were investigated using fluorescence and UV‐visible absorption spectra. K+, Pb2+, Cd2+ and Ba2+ enhance the fluorescence of the polymer; in contrast, Hg2+ causes effective quenching of the fluorescence of the polymer. The obvious influences on the fluorescence indicate that the 2,2′‐binaphtho‐20‐crown‐6 moiety plays an important role in fluorescence recognition for Hg2+ due to the effective photo‐induced electron transfer or charge transfer between the conjugated polymer backbone and the receptor ions. The responsive properties of the polymer to metal ions show that the chiral conjugated polymer incorporating 2,2′‐binaphtho‐20‐crown‐6 moieties in the main‐chain backbone as recognition sites can act as an excellent fluorescent probe for the sensitive detection of Hg2+. Copyright © 2010 Society of Chemical Industry

Recent Progress in Functional Materials for Selective Detection and Removal of Mercury(II) Ions

“…Reproduced with permission. [ 11c ] Copyright 2014, Royal Society of Chemistry. C) Fluorescence emission spectra of P2 under different conditions: P2 (red line); P2 + Hg 2+ (blue line); P2 + GdL (black line); P2 + GdL + Hg 2+ (green line).…”

“…Subsequently, Feng and co‐workers designed an upconversion LRET system taking advantage of hydrophobic–hydrophobic interactions via a convenient strategy, namely, Ru1‐UCNPs, for sensing Hg 2+ in aqueous solution. [ 11c ] In this system, Ru1‐UCNPs including amphiphilic polymer‐functionalized NaYF 4 (20% Yb, 1.6% Er, 0.4% Tm) nanophosphors provided an approach for the facile loading of mercury ions responsive Ru II complex. Coating the amphiphilic poly(maleic anhydride‐ alt ‐1‐octadecene)polyethylene glycol (C18PMH‐PEG) on the upconversion nanophosphors (UCNPs), the obtained hybrid material was prepared with great dispersibility in water.…”

“…Second, polymeric materials possessing particular reacting moieties, favorable structures, and stimuli‐responsive properties have been constructed as satisfactory options of chemical sensing. [ 7i,11 ] Undoubtedly, enormous polymeric probes including pH‐responsive and thermal‐responsive systems have superiorities of prominent recyclability, low cost, and green detection for the application in real samples. [ 12 ] Third, novel applicable probes with aggregation‐induced emission (AIE)‐active characteristics also play a crucial part in selective detection and thorough removal of harmful pollutants.…”