Perturbation of planarity as the possible mechanism of solvent-dependent variations of fluorescence quantum yield in 2-aryl-3-hydroxychromones.
In order to understand the unexpectedly low quantum yields of 3-hydroxyflavones (3-HFs) in certain solvents, such as acetonitrile or ethyl acetate, the comparative study of solvent-dependent properties of parent 3-HF, 2-furyl-3-hydroxychromone and 2-benzofuryl-3-hydroxychromone derivatives have been performed. The results suggest that the formation of intermolecular hydrogen bond of 3-hydroxy group with the solvent favors non-planar conformations of phenyl group with respect to chromone system. This steric hindrance is not observed in the case of furan- and benzofuran-substituted 3-hydroxychromones (3-HCs). These results suggesting a new strategy for dramatic improvement of fluorescence properties of 3-HCs as two-wavelength ratiometric fluorescence probes.
Klymchenko
Andrey S
AS
Research Institute for Genetic Engineering and Biotechnology, TUBITAK Marmara Research Center, Gebze-Kocaeli 41470, Turkey.
Pivovarenko
Vasyl G
VG
Demchenko
Alexander P
AP
D002867:Chromones / Q000737:chemistry*; D005419:Flavonoids / Q000737:chemistry*; D008956:Models, Chemical; D011522:Protons; D012997:Solvents / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013053:Spectrophotometry
C479534:3-hydroxychromone; D002867:Chromones; D005419:Flavonoids; D011522:Protons; D012997:Solvents; C041477:3-hydroxyflavone