TY - JOUR
T1 - Cyanide and fluoride colorimetric sensing by novel imidazo-anthraquinones functionalised with indole and carbazole
AU - Batista, Rosa M. F.
AU - Oliveira, Elisabete
AU - Costa, Susana P. G.
AU - Lodeiro, Carlos
AU - Raposo, M. Manuela M.
N1 - Thanks are due to the Foundation for the Science and Technology (FCT, Portugal) for financial support to the NMR Portuguese network (PTNMR, Bruker Avance III 400-Univ. Minho), FCT and FEDER (European Fund for Regional Development)-COMPETE-QREN-EU for financial support to the Research Centre, CQ/UM [PEst-C/QUI/UI0686/2011 (FCOMP-01-0124-FEDER-022716)] and the post-doctoral grants to R.M.F. Batista (SFRH/BPD/79333/2011) and E. Oliveira (SFRH/BPD/72557/2010).
PY - 2014/2/1
Y1 - 2014/2/1
N2 - Novel imidazo-anthraquinones functionalised with indole and carbazole have been synthesised and characterised and their evaluation as colorimetric chemosensors was carried out in acetonitrile as well as in acetonitrile/H2O (97:3) in the presence of several anions such as F-, Cl-, Br-, I-, CN-, NO3-, ClO4-, AcO-, BzO(-), NO3-, ClO4-, HSO4-, and H2PO4-. In addition, their behaviour in the presence of H+ and OH- was also studied. Upon addition of CN- and F- to acetonitrile solutions of compounds 1-3, a marked colour change from yellow to orange was observed and the fluorescence emission of 1 and 2 was switched on'. The recognition in organic aqueous solution leads to the selective and sensitive naked-eye detection (mM) of CN- for all receptors, with an easily detectable colour change from yellow to orange. The binding stoichiometry between the receptors and the anions was found to be 2:1. The binding process was also followed by H-1 NMR titrations showing that two different binding modes occurred in the presence of fluoride or cyanide anions, which is in agreement with the spectrophotometric titrations.
AB - Novel imidazo-anthraquinones functionalised with indole and carbazole have been synthesised and characterised and their evaluation as colorimetric chemosensors was carried out in acetonitrile as well as in acetonitrile/H2O (97:3) in the presence of several anions such as F-, Cl-, Br-, I-, CN-, NO3-, ClO4-, AcO-, BzO(-), NO3-, ClO4-, HSO4-, and H2PO4-. In addition, their behaviour in the presence of H+ and OH- was also studied. Upon addition of CN- and F- to acetonitrile solutions of compounds 1-3, a marked colour change from yellow to orange was observed and the fluorescence emission of 1 and 2 was switched on'. The recognition in organic aqueous solution leads to the selective and sensitive naked-eye detection (mM) of CN- for all receptors, with an easily detectable colour change from yellow to orange. The binding stoichiometry between the receptors and the anions was found to be 2:1. The binding process was also followed by H-1 NMR titrations showing that two different binding modes occurred in the presence of fluoride or cyanide anions, which is in agreement with the spectrophotometric titrations.
KW - anthraquinone
KW - aqueous media
KW - cyanide
KW - fluoride
KW - imidazole
KW - naked-eye detection
U2 - 10.1080/10610278.2013.824082
DO - 10.1080/10610278.2013.824082
M3 - Article
SN - 1061-0278
VL - 26
SP - 71
EP - 80
JO - Supramolecular Chemistry
JF - Supramolecular Chemistry
IS - 2
ER -