In:
Journal of Porphyrins and Phthalocyanines, World Scientific Pub Co Pte Ltd, Vol. 07, No. 06 ( 2003-06), p. 399-404
Kurzfassung:
The porphyrin 5,10,15,20-tetrakis[4-(1,4,7,10,13-pentaoxacyclopentadecane-2-aminomethyl)2,3,5,6-tetrafluorophenyl]porphyrin,T15C5P, was synthesized by the reaction of 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin with the crown ether 2-aminomethyl-(15-crown-5). The crowned porphyrin showed a distinct spectroscopic behavior in the presence of sodium and potassium ions. Dimerization studies based on absorption measurements clearly indicate that T15C5P aggregates in the presence of potassium ions in chloroform/methanol medium (1.0 × 10 −5 mol.L −1 or 1.0 × 10 −4 mol.L −1 ), with a dimerization constant ( K D ) of 2.14 × 10 −5 and 2.23 × 10 −5 , respectively. The same formalism applied to the T15C5P in the presence of sodium ions indicated absence of the aggregation process. The ionic radius of Na + is suitable to fit well into the cavity of 15-crown-5 moieties, leading to intramolecular complexes only. Potassium ion is too large to lie in the hole of the crown ether entities and is probably located between two porphyrin molecules, promoting 2:1 aggregated complexes through it's sandwiching, as is observed for phthalocyanines.
Materialart:
Online-Ressource
ISSN:
1088-4246
,
1099-1409
DOI:
10.1142/S1088424603000513
Sprache:
Englisch
Verlag:
World Scientific Pub Co Pte Ltd
Publikationsdatum:
2003
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