meso-Tetraarylporpholactones as high pH sensors.
The ability of meso-tetra(pentafluorophenyl)porpholactone (T(F)PL) and its Pt(II) complex [meso-tetra(pentafluorophenyl)porpholactonato]Pt(II) (T(F)PLPt) to function as optical high pH sensors is described. Under strongly alkaline or high methoxide conditions, their UV-vis spectra undergo dramatic and reversible red-shifts. The dynamic range for the sensor T(F)PLPt in solution is from pH 11.5 to 13.2. Using (1)H, (19)F, and (13)C NMR, UV-vis and IR spectroscopy, mass spectrometry, and the use of model compounds, the molecular origin of this optical shift is deduced to be a nucleophilic attack of OH(-)/MeO(-) on the lactone carbonyl of the chromophore, representing a novel mechanism for porphyrin-based sensors. The sensing compound was solubilized with Cremophor EL for use in aqueous solutions and embedded in polymer matrixes for testing as optical fiber-based optodes and planar sheet optode materials.
Khalil
Gamal E
GE
Department of Chemistry, University of Washington, Box 351700, Seattle, WA 98195-1700, USA. gamalk@u.washington.edu
Daddario
Pedro
P
Lau
Kimberly S F
KS
Imtiaz
Sayed
S
King
Michelle
M
Gouterman
Martin
M
Sidelev
Alexey
A
Puran
Narissa
N
Ghandehari
Masoud
M
Brückner
Christian
C
D004563:Electrochemistry; D004566:Electrodes; D006863:Hydrogen-Ion Concentration; D009944:Organoplatinum Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D011166:Porphyrins / Q000138:chemical synthesis / Q000737:chemistry*; D005464:Fluorobenzenes; D005466:Fluorocarbons
D009944:Organoplatinum Compounds; D011166:Porphyrins; C554137:meso-tetra(pentafluorophenyl)porpholactone; D005464:Fluorobenzenes; D005466:Fluorocarbons