title: Synthesis, spectroscopy, crystal structure, electrochemistry, and quantum chemical and molecular dynamics calculations of a 3-anilino difluoroboron dipyrromethene dye.
abstract: An asymmetrically substituted fluorescent difluoroboron dipyrromethene (BODIPY) dye, with a phenylamino group at the 3-position of the BODIPY chromophore, has been synthesized by nucleophilic substitution of 3,5-dichloro-8-(4-tolyl)-4,4-difluoro-4-bora-3a,4a-diaza-s-indacene. The solvent-dependent spectroscopic and photophysical properties have been investigated by means of UV-vis spectrophotometry and steady-state and time-resolved fluorometry and reflect the large effect of the anilino substituent on the fluorescence characteristics. The compound has a low fluorescence quantum yield in all but the apolar solvents cyclohexane, toluene, and chloroform. Its emission maxima in a series of solvents from cyclohexane to methanol are red-shifted by approximately 50 nm in comparison to classic BODIPY derivatives. Its oxidation potential in dichloromethane is at ca. 1.14 V versus Ag/AgCl. The absorption bandwidths and Stokes shifts are much larger than those of typical, symmetric difluoroboron dipyrromethene dyes. The values of the fluorescence rate constant are in the (1.4-1.7) x 10(8) s(-1) range and do not vary much between the solvents studied. X-ray diffraction analysis shows that the BODIPY core is planar. Molecular dynamics simulations show that there is no clear indication for aggregates in solution.
authors.affiliation: Department of Chemistry, Katholieke Universiteit Leuven, Leuven, Belgium.
authors.forename: Wenwu
authors.initials: W
authors.lastname: Qin
authors.forename: Volker
authors.initials: V
authors.lastname: Leen
authors.forename: Taoufik
authors.initials: T
authors.lastname: Rohand
authors.forename: Wim
authors.initials: W
authors.lastname: Dehaen
authors.forename: Peter
authors.initials: P
authors.lastname: Dedecker
authors.forename: Mark
authors.initials: M
authors.lastname: Van der Auweraer
authors.forename: Koen
authors.initials: K
authors.lastname: Robeyns
authors.forename: Luc
authors.initials: L
authors.lastname: Van Meervelt
authors.forename: David
authors.initials: D
authors.lastname: Beljonne
authors.forename: Bernard
authors.initials: B
authors.lastname: Van Averbeke
authors.forename: John N
authors.initials: JN
authors.lastname: Clifford
authors.forename: Kris
authors.initials: K
authors.lastname: Driesen
authors.forename: Koen
authors.initials: K
authors.lastname: Binnemans
authors.forename: Noël
authors.initials: N
authors.lastname: Boens
mesh_terms: D000042:Absorption; D004396:Coloring Agents / Q000138:chemical synthesis* / Q000737:chemistry; D018360:Crystallography, X-Ray; D004563:Electrochemistry; D005740:Gases / Q000737:chemistry; D007700:Kinetics; D008958:Models, Molecular; D008968:Molecular Conformation; D011162:Porphobilinogen / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D011789:Quantum Theory; D012997:Solvents / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet
chemical_list: C538930:3-anilino difluoroboron dipyrromethene; D004396:Coloring Agents; D005740:Gases; D012997:Solvents; D011162:Porphobilinogen