Article

Monodisperse fluorene oligomers exhibiting strong dipolar coupling interactions.

Laboratoire de Stéréochimie et Interactions Moléculaires, ENS-Lyon and CNRS, 46 Allée d'Italie, 69364 Lyon, France.
Chemical Communications (Impact Factor: 6.72). 09/2002; DOI: 10.1039/B201414A
Source: PubMed

ABSTRACT Well-defined fluorene oligomers (n = 1 to 6) were prepared step by step using Suzuki and Yamamoto couplings, while absorption and photoluminescence properties evidenced very large dipolar coupling interactions between fluorene moieties.

0 Bookmarks
 · 
53 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Four novel dyes are prepared by thiophene as π bridge between carbazole central core and other terminal groups by Suzuki and Heck coupling reactions. These dyes are fully characterized by IR, 1H NMR, 13C NMR, MS and elemental analysis. Linear absorption, single- and two-photon excited fluorescence in various solvents are experimentally investigated. The calculated two-photon absorption cross sections of 9-Hexyl-3,6-di((5-phenyl)-2-thienyl)carbazole (1), 9-Hexyl-3,6-di((5-thienyl)-2-thienyl)carbazole (2), 9-Hexyl-3,6-di((5-p-vinylpyridyl)-2-thienyl)-carbazole (3) and 9-Hexyl-3,6-di-((5-o-vinylpyridyl)-2-thienyl)carbazole (4) for the lowest excited state are 537.84, 550.76, 1292.95 and 1340.40 × 10−50 cm4 s photon−1, respectively. Calculated and experimental data have shown that thiophene as π electron bridge improves the two-photon absorption cross sections greatly. Two-photon optical data recording experiments have been carried out at 820 nm laser radiation.
    Dyes and Pigments 01/2012; 92(1):633–641. · 3.47 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The solution process is more suitable for large-sized OLED in terms of small material usage and no need for fine mask patterning technique. Among soluble materials, dendrimers are acknowledged as a new class of emissive OLED materials that can carry both the emissive chromophore and the charge transporting moiety simultaneously. Here, we report on a new Ir(III)-based dendrimer and an efficient single emission layer OLED device by spin-coating the dendrimer itself on PEDOT:PSS polymer. This dendrimer carries a pair of carbazole functional groups on the pyridine side and a fluorinated phenyl on the other side of the Ir(ppy)3 ligand. The latter functional group acts as an electron transporting material and the former as a host and hole-transporting material. The dendrimer device has a green emission at 540 nm with current efficiency as high as 25 Cd/A. Interestingly, we have found that the two neighboring carbazole form the electromer under the applied electrical current and, thus, that the EL device shows new near-IR emission over 720 nm.
    Synthetic Metals 09/2010; 160(s 17–18):1994–1999. · 2.22 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Experimental approaches to tetraphosphonate cavitands bearing fluorenyl-phosphonate bridges are reported. Different routes are described depending on the substitution on the cavitand structure. Tetra-, tri- and di-bridged phosphonate cavitands have been prepared as precursors of fluorescent hosts, for which the stereochemistry is highly dependent on the substitution at the wide rim of the resorcin[4]arene scaffold. The conformational change in 3io tetraphosphonate cavitands has been characterised by X-ray diffraction. These new molecular receptors have been used for the recognition of acetylcholine.
    Supramolecular Chemistry 09/2013; 25. · 2.13 Impact Factor