Synthesis and characterization of novel indole-containing half-crowns as new emissive metal probes

Two new indole derivatives have been synthesized by a one-pot procedure and their potential as fluorescence probes for metal ions was investigated. The sensor capability of 1 and 2 toward cations such as Ag+, Cu2+ Zn2+, Cd2+, Pb2+, and Hg2- was studied in dichloromethane solution by absorption, fluorescence emission, and H-1 NMR titrations. Both probes showed selectivity for Ag+ and Hg2+ ions. The results suggest that these compounds may serve as promising models for future design of novel and more potent sensors. (C) 2009 Elsevier Ltd. All rights reserved.