Loading…

Formation of a new hybrid complex via coordination interaction between 5,10,15-tritolyl-20-(4- and 3-pyridyl)porphyrin or 5,10,15-triphenyl-20-(4-pyridyl)porphyrin and the α-[MSiW 11O 39] 6− Keggin-type polyoxometalate (M = Co 2+ and Ni 2+)

Evidence for the formation of a new complex based on the association of 5,10,15-tritolyl-20-(4- and 3-pyridyl)porphyrin or 5,10,15-triphenyl-20-(4-pyridyl)porphyrin and α-[MSiW 11O 39] 6− (M = Co 2+ and Ni 2+) Keggin-type polyoxometalate is given by steady-state and time-resolved luminescence and pa...

Full description

Saved in:
Bibliographic Details
Published in:Inorganica Chimica Acta 2010-06, Vol.363 (10), p.2185-2192
Main Authors: Schaming, D., Costa-Coquelard, C., Lampre, I., Sorgues, S., Erard, M., Liu, X., Liu, J., Sun, L., Canny, J., Thouvenot, R., Ruhlmann, L.
Format: Article
Language:English
Subjects:
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Evidence for the formation of a new complex based on the association of 5,10,15-tritolyl-20-(4- and 3-pyridyl)porphyrin or 5,10,15-triphenyl-20-(4-pyridyl)porphyrin and α-[MSiW 11O 39] 6− (M = Co 2+ and Ni 2+) Keggin-type polyoxometalate is given by steady-state and time-resolved luminescence and paramagnetic 1H NMR. New complexes based on a coordination interaction between a pyridyl-porphyrin (namely 5,10,15-tritolyl-20-(4-pyridyl)porphyrin, 5,10,15-tritolyl-20-(3-pyridyl)porphyrin or 5,10,15-triphenyl-20-(4-pyridyl)porphyrin) and a Keggin-type polyoxometalate (α-[MSiW 11O 39] 6−, M = Co 2+ or Ni 2+) are formed in solution. The formation of these complexes is clearly evidenced by steady-state and time-resolved luminescence measurements. A strong quenching of the porphyrin fluorescence, accompanied by an important shortening of the fluorescence lifetime, is observed upon addition of the POM and formation of the complexes. Using a variant of the Job’s method from the luminescence spectra, the association constants of the complexes have been estimated to be around 10 6 L mol −1. Paramagnetic 1H NMR experiments confirm the formation of the complexes. Indeed, in addition to broadenings of the signals, the coordination binding of the POM to the porphyrin induces large high-frequency shifts for the protons of the pyridyl group coordinated to the paramagnetic metal, and low-frequency shifts for all the other resonances.
ISSN:0020-1693
1873-3255
DOI:10.1016/j.ica.2010.03.015