Fluorescent carbazolylurea- and carbazolylthiourea-based anion receptors and sensors

Abstract

A series of carbazolylurea- and carbazolylthiourea-based receptors have been synthesised and their anion complexation and fluorescence properties were studied. The urea compounds show selectivity for oxo-anion complexation over chloride and the fluorescence of compound 1 is selectively quenched by benzoate anions in DMSO/0.5% water. However, the thiourea compounds show reduced anion affinities compared to the urea analogues.

Keywords:

• anion binding
• indole
• hydrogen bonding
• crystallography

Acknowledgements

We thank the EPSRC for studentship funding (J.R.H) and for access to the crystallographic facilities at the University of Southampton. C.C. would like to thank the Italian Ministero dell'Istruzione, dell'Università e della Ricerca Scientifica (MIUR) (Project PRIN-2007C8RW53) and Università degli Studi di Cagliari (fondo 5%) for financial support.