On–Off Switchable Binuclear Chemosensor Based on Thiacalix[4]crown Armed with Pyrene Moieties

✍ Scribed by Manoj Kumar; Abhimanew Dhir; Vandana Bhalla

• Book ID: 102828894
• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 579 KB
• Volume: 2009
• Category: Article
• ISSN: 1434-193X
• DOI: 10.1002/ejoc.200900506

✦ Synopsis

Abstract

A new fluorescent “on–off” switchable chemosensor 2 based on a thiacalix[4] arene with a 1,3‐alternate conformation and two different types of cation binding sites has been synthesized. Two pyrene moieties linked to a cation recognition unit composed of two imine groups form a strong excimer in solution. Of the metal ions tested, the fluorescence of 2 was strongly quenched by Hg^2+^, Pb^2+^ and Cu^2+^ ions. The fluorescence was revived by the addition of only K^+^ to the Cu^2+^ ligand complex. Thus, metal‐ion exchange triggers an “on–off” switchable fluorescent chemosensor. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)