title: Photophysics of 3,5-diphenoxy substituted BODIPY dyes in solution.
abstract: We have prepared two fluorescent dyes derived from 8-(4-tolyl)-4,4-difluoro-4-bora-3a,4a-diaza-s-indacene with phenoxy and (o-bromo)phenoxy substituents at the 3,5-positions by a novel nucleophilic substitution reaction of the corresponding 3,5-dichloroBODIPY analogue. UV-vis absorption, steady-state and time-resolved fluorimetry have been used to investigate their solvent-dependent photophysical properties. The two BODIPY derivatives show narrow absorption and emission bands and display small Stokes shifts. The substituents at the 3,5-positions (phenoxy in 1 and o-bromophenoxy in 2) have a minor effect on the fluorescence quantum yields (0.16-0.40 for 1, 0.17-0.44 for 2) and lifetimes (1.09-2.51 ns for 1, 1.11-2.78 ns for 2). For both compounds, the fluorescence rate constant equals (1.5 +/- 0.1) x 10(8) s(-1).
authors.affiliation: Department of Chemistry and Institute for Nanoscale Physics and Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200f - bus 02404, 3001, Leuven, Belgium.
authors.forename: Taoufik
authors.initials: T
authors.lastname: Rohand
authors.forename: Jess
authors.initials: J
authors.lastname: Lycoops
authors.forename: Steve
authors.initials: S
authors.lastname: Smout
authors.forename: Els
authors.initials: E
authors.lastname: Braeken
authors.forename: Michel
authors.initials: M
authors.lastname: Sliwa
authors.forename: Mark
authors.initials: M
authors.lastname: Van der Auweraer
authors.forename: Wim
authors.initials: W
authors.lastname: Dehaen
authors.forename: Wim M
authors.initials: WM
authors.lastname: De Borggraeve
authors.forename: Noël
authors.initials: N
authors.lastname: Boens