TY - JOUR
T1 - Sensing metal ions with two new azomethine-thiophene pincer ligands (NSN): Fluorescence and MALDI-TOF-MS applications
AU - Pedras, Bruno
AU - Santos, Hugo M.
AU - Fernandes, Luz
AU - Covelo, Berta
AU - Tamayo, Abel
AU - Bértolo, Emilia
AU - Capelo, José Luis
AU - Avilés, Teresa
AU - Lodeiro, Carlos
N1 - We are indebted to Fundação para a Ciência e a Tecnologia (FCT)/FEDER (Portugal/EU) (Project POCI/QUI/55519/2004 FCT-FEDER), and Canterbury Christ Church University Research Fund for financial support. E.B., J.L.C. and C.L. also thank bilateral program “Acções integradas Luso-Británicas 2006” for the bilateral agreement numbers B-16/06 and B-61/07. B.P. acknowledges the FCT/Portugal by the PhD Grant SFRH/BD/27786/2006.
PY - 2007/8/1
Y1 - 2007/8/1
N2 - The two new pincer azomethine-thiophene ligands (N,NE′,N,NE′)-N,N′-(thiophene-2,5-diylbis(methan-1-yl-1-ylidene))bis(naphathalen-2-ylmethanamine) (L1) and (E)-(4,6-dihydropyren-1-yl)-N-((5-((E)-(pyren-1-ylmethylimino)ethyl)thiophen-2-yl)methylene)methanamine (L2), their absorption, fluorescence and MALDI-TOF-MS spectroscopic studies are described. The two systems synthesised combine the emissive probes pyrene and naphthyl with the good chelating properties of a tridentate SN2 donor-set from a thiophene Schiff-base ligand. Both ligands gave analytically pure solid complexes with Ni(II) and Pd(II) salts. The bichromophoric pyrene derivative L2 presents two emission bands in solution, one corresponding to the monomer species and a red-shifted band attributable to the intramolecular excimer. Ni(II) and Pd(II) complexation affects the conformation in solution, increasing the monomer emission at the expense of the excimer band; this effect could be explored in metal ion sensing. System L1 behaves as a non emissive probe. In situ complexation reactions followed by MALDI-TOF-MS spectrometry without matrix support have also been performed; these experiments show that L1 could be a potential chemosensor for Ni(II) and Pd(II).
AB - The two new pincer azomethine-thiophene ligands (N,NE′,N,NE′)-N,N′-(thiophene-2,5-diylbis(methan-1-yl-1-ylidene))bis(naphathalen-2-ylmethanamine) (L1) and (E)-(4,6-dihydropyren-1-yl)-N-((5-((E)-(pyren-1-ylmethylimino)ethyl)thiophen-2-yl)methylene)methanamine (L2), their absorption, fluorescence and MALDI-TOF-MS spectroscopic studies are described. The two systems synthesised combine the emissive probes pyrene and naphthyl with the good chelating properties of a tridentate SN2 donor-set from a thiophene Schiff-base ligand. Both ligands gave analytically pure solid complexes with Ni(II) and Pd(II) salts. The bichromophoric pyrene derivative L2 presents two emission bands in solution, one corresponding to the monomer species and a red-shifted band attributable to the intramolecular excimer. Ni(II) and Pd(II) complexation affects the conformation in solution, increasing the monomer emission at the expense of the excimer band; this effect could be explored in metal ion sensing. System L1 behaves as a non emissive probe. In situ complexation reactions followed by MALDI-TOF-MS spectrometry without matrix support have also been performed; these experiments show that L1 could be a potential chemosensor for Ni(II) and Pd(II).
KW - Fluorescent chemosensors
KW - MALDI-TOF-MS
KW - Nickel(II)
KW - Palladium(II)
KW - Thiophene
UR - http://www.scopus.com/inward/record.url?scp=34447561738&partnerID=8YFLogxK
U2 - 10.1016/j.inoche.2007.05.001
DO - 10.1016/j.inoche.2007.05.001
M3 - Article
AN - SCOPUS:34447561738
SN - 1387-7003
VL - 10
SP - 925
EP - 929
JO - Inorganic Chemistry Communications
JF - Inorganic Chemistry Communications
IS - 8
ER -