A new dual fluorogenic and chromogenic "turn-on" chemosensor for Cu<SUP>2+</SUP>/F<SUP>-</SUP> ions

Abstract

Turn "off-on" chemosensor 2-(-2-((3',6'-bis(diethylamino)-3-oxospiro[isoindoline-1,9'-xanthen]-2-yl)imino)ethylidene)-N-phenylhydrazine-1-carbothioamide (RBS) was designed and synthesized. Using the naked eye, RBS showed favorable observation characteristics with both Cu2+ and F- ions. The various modes of sensitivity shown by RBS toward the Cu2+ and F- ions were investigated by spectral techniques, including UV-Vis, fluorescence and H-1 NMR spectroscopy. The Job's plot indicated the formation of 1:1 complex between RBS and Cu2+/F-. The binding constant of the RBS-guest(-) complexes were found to be 1.3 x 10(4) and 6.2 x 10(3) M-1 for the RBS-Cu2+ and RBS-F-, respectively. (C) 2015 Elsevier B.V. All rights reserved.