TY - JOUR
T1 - Novel emissive podands based on 8-OH-quinoline: Synthesis, fluorescence materials, DFT and complexation studies
AU - Fernández-Lodeiro, Javier
AU - Núñez, Cristina
AU - Nieto Faza, Olalla
AU - Capelo, José Luis
AU - Lodeiro, Carlos
AU - Melo, J. Sérgio Seixas de
AU - López, Carlos Silva
N1 - We are grateful to Xunta de Galicia (Spain) for projects 09CSA043383PR and 10CSA383009PR (Biomedicine) and to the Scientific Association Proteomass for financial support. J.F.L. Thanks Xunta de Galicia (Spain) for a research contract by project 09CSA043383PR in Biomedicine. C.N. thanks the Fundacao para a Ciencia e a Tecnologia/FEDER (Portugal/EU) programme postdoctoral contract SFRH/BPD/65367/2009. C. S. L., J.L.C. and C. L. thank Xunta de Galicia for the Isidro Parga Pondal Research programme.
PY - 2012/2/15
Y1 - 2012/2/15
N2 -
Two novel chemosensors with podand structures (L
1
and L
2
) derived from 1,5-bis(2-aminophenoxy)-3-oxopenthane bearing two flexible 8-hydroxyquinoline units have been synthesized and characterized. Several nitrate complexes of transition (Cu
2+
), post-transition (Zn
2+
) and lanthanide (Eu
3+
and Sm
3+
) metal ions have been synthesized with tetrafluoroborate salts and characterized. In order to study their potential utility as fluorescent probes, the coordination ability of chemosensors (L
1
and L
2
) towards those metal ions has been explored in solution (by UV-Vis and emission spectroscopy) and in gas phase (by MALDI mass spectrometry). Density functional theory has been employed to explore the emission properties of the three-protonation states of the chemosensor. From this study, the anomalous red shift observed in the fluorescence spectra of the dianionic sensors can be attributed to subtle structural differences between their anionic and dianionic forms. Furthermore, a plausible explanation for the low fluorescence of the neutral form is provided in the form of a non-radiative relaxation involving the imine double-bond isomerization. All new compounds have been characterized by microanalysis, melting points, IR, UV-Vis and fluorescence emission spectroscopy and MALDI-TOF-mass spectrometry.
AB -
Two novel chemosensors with podand structures (L
1
and L
2
) derived from 1,5-bis(2-aminophenoxy)-3-oxopenthane bearing two flexible 8-hydroxyquinoline units have been synthesized and characterized. Several nitrate complexes of transition (Cu
2+
), post-transition (Zn
2+
) and lanthanide (Eu
3+
and Sm
3+
) metal ions have been synthesized with tetrafluoroborate salts and characterized. In order to study their potential utility as fluorescent probes, the coordination ability of chemosensors (L
1
and L
2
) towards those metal ions has been explored in solution (by UV-Vis and emission spectroscopy) and in gas phase (by MALDI mass spectrometry). Density functional theory has been employed to explore the emission properties of the three-protonation states of the chemosensor. From this study, the anomalous red shift observed in the fluorescence spectra of the dianionic sensors can be attributed to subtle structural differences between their anionic and dianionic forms. Furthermore, a plausible explanation for the low fluorescence of the neutral form is provided in the form of a non-radiative relaxation involving the imine double-bond isomerization. All new compounds have been characterized by microanalysis, melting points, IR, UV-Vis and fluorescence emission spectroscopy and MALDI-TOF-mass spectrometry.
KW - 8H-quinoline
KW - Chemosensor
KW - Fluorescence
KW - MALDI-TOF-MS
KW - Metal ions
KW - Nanoparticles
UR - http://www.scopus.com/inward/record.url?scp=84857042987&partnerID=8YFLogxK
U2 - 10.1016/j.ica.2011.09.018
DO - 10.1016/j.ica.2011.09.018
M3 - Article
AN - SCOPUS:84857042987
SN - 0020-1693
VL - 381
SP - 218
EP - 228
JO - Inorganica Chimica Acta
JF - Inorganica Chimica Acta
IS - 1
ER -