123863-97-8Relevant articles and documents
Tunable fluorene-based dynamers through constitutional dynamic chemistry
Giuseppone, Nicolas,Fuks, Gad,Lehn, Jean-Marie
, p. 1723 - 1735 (2006)
Dynamic covalent imino-fluorene-based oligomers and polymers have been generated. They undergo constitutional recomposition under the effect of two parameters, acidity and ZnII metal ions. As a result, marked changes in physical properties take
Microwave-assisted FeCl3-mediated rapid synthesis of poly(9,9-dihexylfluorene) with high molecular weight
Zhang, Wensi,Wang, Zhiming,Zhang, Yunan,Lu, Ping,Liu, Linlin,Ma, Yuguang
, p. 5346 - 5349 (2014)
Poly(9,9-dihexylfluorene) with high molecular weight (Mw ～ 81,000) is obtained in 25 min using a microwave-assisted FeCl3-mediated oxidative polymerization. The effects of microwave power, time, solvent, monomer and catalyst's concentration on the polymerization have been systematically investigated. The structures and thermal properties of obtained polymers are fully characterized using FTIR, NMR, TGA, DSC, UV-visible absorption and fluorescence spectra. The results show that well-defined polymers have been obtained. XPS, ICP and elemental analysis are used to check the residue of iron catalyst, and almost no residue of FeCl3 is detected in polymers.
Facile C?H alkylation in water: Enabling defect-free materials for optoelectronic devices
Saikia, Gunin,Iyer, Parameswar K.
, p. 2714 - 2717 (2010)
A facile method for the alkylation of fluorene achieved via direct C?H alkylation under aqueous conditions is reported, wherein the formation of fluorenone is inhibited, resulting in the exclusive formation of the desired dialkyl-substituted fluorene monomer. As a proof of concept, this method has also been successfully extended to perform N-alkylation of carbazole, diphenylamine, and N,N-dialkylation of aniline in high yields.
Synthesis and energy-transfer properties of hydrogen-bonded oligofluorenes
Dudek, Stephen P.,Pouderoijen, Maarten,Abbel, Robert,Schenning, Albertus P. H. J.,Meijer
, p. 11763 - 11768 (2005)
A set of fluorene oligomers has been synthesized by stepwise palladium-catalyzed (Suzuki) couplings of fluorene monomers. Ureidopyrimidinones (UPy), functional groups that can dimerize via quadruple hydrogen bonds, were attached to both ends of the oligof
Understanding the reversible anodic behaviour and fluorescence properties of fluorenylazomethines A structure-property study
Barik, Satyananda,Friedland, Sayuri,Skene
, p. 945 - 953 (2010)
A series of fluorenylazomethine dyads and triads were prepared by simple condensation between the corresponding amine and aldehyde fluorene derivatives. These compounds were prepared as model compounds for investigating the effects of substitution and electronic groups on both the electrochemical properties and fluorescence quantum yields. It was found that the oxidation potential could be decreased by both incorporating electron donating groups and increasing the degree of conjugation. It was further found that alkylation in the fluorene's 9-position increased the azomethine degree of conjugation by forcing all the fluorene moieties to be coplanar with the azomethine bonds to which they are attached. Meanwhile, reversible radical cation behaviour was possible by substituting the terminal 2,2′-positions with atoms other than hydrogen. The radical cation was theoretically found to be distributed evenly across the fluorene, corroborating the reversible anodic behaviour with 2,2′-substitution. The fluorescence quantum yields of the azomethines were not found to be dependent on substitution. This was because the azomethine fluorescence was found to be quenched relative to their precursors regardless of substitution. The fluorescence could be restored at both low temperature and by acid protonation.
Synthesis and crystal structure and optical properties of fluorenic-core oligomers
Destri, Silvia,Pasini, Mariacecilia,Botta, Chiara,Porzio, William,Bertini, Fabio,Marchio, Luciano
, p. 924 - 933 (2002)
Fluorenic core oligomers, displaying interesting photoluminescence properties, have been synthesized by an organometallic route. The crystal and molecular structure of a fluorene derivative and three homologous oligomers have been studied. The spiro-deriv
A fluorene-based material containing triple azacrown ether groups: Synthesis, characterization and application in chemosensors and electroluminescent devices
Wu, Chia-Shing,Lin, Ying-Ju,Chen, Yun
, p. 1419 - 1429 (2014)
We design a novel multifunctional fluorene-based material containing triple azacrown ether (FTC) not only for application in aqueous solution as a chemosensor towards Fe3+ but also to enhance the electroluminescence of PLEDs using an environmentally stable aluminum cathode. The photo-physical and sensing properties were investigated by absorption and photoluminescence (PL) spectroscopy. The FTC exhibited specific selectivity and high sensitivity toward Fe3+, with the Stern-Volmer coefficients (Ksv) being 1.59 × 105 M-1 in a solvent mixture of tetrahydrofuran and water (THF-H2O = 9/1, v/v). The FTC maintained high selectivity toward Fe3+ in the presence of ten interfering metal cations. The HOMO and LUMO levels were estimated to be -5.88 eV and -2.88 eV, respectively. The FTC significantly enhances the emission performance of PLEDs [ITO/PEDOT:PSS/MEH-PPV/EIL/Al] when used as an electron injection layer (EIL), especially in the presence of metal carbonates. Particularly, the device using K2CO3 doped FTC as the electron-injection layer (EIL) exhibited significantly enhanced performance compared to the one without EIL. The performance was significantly enhanced to 11630 cd m-2 and 1.47 cd A-1, respectively, from 230 cd m-2 and 0.03 cd A -1 of the non-FTC device. Current results indicate that multifunctional fluorene-based material FTC is a potential candidate for selective detection of Fe3+ and as an effective electron injection layer to enhance the performance of MEH-PPV.
Supported composite metallocene catalyst, its preparation method and use the catalyst method for preparing polyolefin
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Paragraph 0119 - 0122, (2017/08/02)
Provided are a hybrid supported metallocene catalyst, a method for preparing the same, and a process for preparing an olefin polymer using the same, and more particular, a hybrid supported metallocene catalyst characterized in that two kinds of metallocene compounds containing a new cyclopenta[b]fluorenyl transition metal compound are supported on an inorganic or organic porous carrier surface-treated with an ionic compound and a co-catalyst, a method for preparing the same, and a process for preparing an olefin polymer using the hybrid supported metallocene catalyst.
