- Tunable fluorene-based dynamers through constitutional dynamic chemistry
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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
- Giuseppone, Nicolas,Fuks, Gad,Lehn, Jean-Marie
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- New quaternary phosphonium salt as multi-site phase-transfer catalyst for various alkylation reactions
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The present work describes the C-alkylation reactions of fluorene and curcumin catalyzed by a new phosphonium salt, benzene-1,3,5-triyltris(methylene))tris(triphenylphosphonium)bromide, as a multi-site phase-transfer catalyst (MPTC). The catalytic efficie
- Ponmuthu, Kottala Vijaya,Kumaraguru, Duraimurugan,Arockiam, Jesin Beneto,Velu, Sadhasivam,Sepperumal, Murugesan,Ayyanar, Siva
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- Microwave-assisted FeCl3-mediated rapid synthesis of poly(9,9-dihexylfluorene) with high molecular weight
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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.
- Zhang, Wensi,Wang, Zhiming,Zhang, Yunan,Lu, Ping,Liu, Linlin,Ma, Yuguang
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- Synthesis and characterization of novel monodisperse starburst oligo(fluoreneethynylene) based on truxene moiety
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A series of novel monodisperse star-shaped oligo(fluoreneethynylene)s, which contain hexahexyltruxene as the central core linked with oligo(fluoreneethynylene) as the arms, are presented. Copyright
- Chen, Qing-Quan,Liu, Feng,Ma, Zhun,Peng, Bo,Wei, Wei,Huang, Wei
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- Facile C?H alkylation in water: Enabling defect-free materials for optoelectronic devices
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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.
- Saikia, Gunin,Iyer, Parameswar K.
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- Crystalline 2D Covalent Organic Framework Membranes for High-Flux Organic Solvent Nanofiltration
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Two-dimensional (2D) covalent organic framework (COF) materials have the most suitable microstructure for membrane applications in order to achieve both high flux and high selectivity. Here, we report the synthesis of a crystalline TFP-DHF 2D COF membrane constructed from two precursors of 1,3,5-triformylphloroglucinol (TFP) and 9,9-dihexylfluorene-2,7-diamine (DHF) through the Langmuir-Blodgett (LB) method, for the first timed. A single COF layer is precisely four unit cells thick and can be transferred to different support surfaces layer by layer. The TFP-DHF 2D COF membrane supported on an anodic aluminum oxide (AAO) porous support displayed remarkable permeabilities for both polar and nonpolar organic solvents, which were approximately 100 times higher than that of the amorphous membranes prepared by the same procedure and similar to that for the best of the reported polymer membranes. The transport mechanism through the TFP-DHF 2D COF membrane was found to be a viscous flow coupled with a strong slip boundary enhancement, which was also different from those of the amorphous polymer membranes. The membrane exhibited a steep molecular sieving with a molecular weight retention onset (MWRO) of approximately 600 Da and a molecular weight cutoff (MWCO) of approximately 900 Da. The substantial performance enhancement was attributed to the structural change from an amorphous structure to a well-defined ordered porous structure, which clearly demonstrated the high potential for the application of 2D COFs as the next generation of membrane materials.
- Shinde, Digambar B.,Sheng, Guan,Li, Xiang,Ostwal, Mayur,Emwas, Abdul-Hamid,Huang, Kuo-Wei,Lai, Zhiping
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- Synthesis and energy-transfer properties of hydrogen-bonded oligofluorenes
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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
- Dudek, Stephen P.,Pouderoijen, Maarten,Abbel, Robert,Schenning, Albertus P. H. J.,Meijer
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- Synthesis and characterization of new blue light emitting poly(arylenevinylene) derivatives containing fluorene pendant
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New poly(arylenevinylene) derivatives composed of biphenyl or terphenyl units in the main chain and fluorene pendant groups are synthesized by Yamamoto coupling reaction or Suzuki coupling reaction. The obtained polymers showed high color pure blue emission due to controlled conjugation length and inhibited intermolecular interaction as well as high solubility and good thermal stability.
- Kim, Yun-Hi,Jung, Sang-Yun,Kwon, Soon-Ki
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- Understanding the reversible anodic behaviour and fluorescence properties of fluorenylazomethines A structure-property study
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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.
- Barik, Satyananda,Friedland, Sayuri,Skene
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- Photolumineseenee wavelength control of fluorene derivatives through h-bonding and protonation
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A fluorene monomer, which comprised 4-pyridylcyanovinyl groups (FL-CNPy), was synthesized, and the photolumineseenee (PL) properties of FL-CNPy combined with various (di)acids were evaluated. Due to hydrogen (H)-bonding or protonation between the pyridine end groups and acids, the PL emission maxima varied from 460 to 557 nm according to the acidity (pKa) and type of (di)acid. Additionally, adjusting the ratio of FL-CNPy/(di)acid tuned the PL emission wavelength without modifying the materials. Copyright
- Kawatsuki, Nobuhiro,Minami, Yuta,Lee, Joenghwan
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- Synthesis and crystal structure and optical properties of fluorenic-core oligomers
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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
- Destri, Silvia,Pasini, Mariacecilia,Botta, Chiara,Porzio, William,Bertini, Fabio,Marchio, Luciano
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- Stabilizing cations in the backbones of conjugated polymers
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We synthesized a cross-conjugated polymer containing ketones in the backbone and converted it to a linearly conjugated, cationic polyarylmethine via a process we call spinless doping to create a new class of materials, conjugated polyions. This process involves activating the ketones with a Lewis acid and converting them to trivalent cations via the nucleophilic addition of electron-rich aryl moieties. Spinless doping lowers the optical band gap from 3.26 to 1.55 eV while leaving the intrinsic semiconductor properties of the polymer intact. Electrochemical reduction (traditional doping) further decreases the predicted gap to 1.18 eV and introduces radicals to form positive polarons; here, n-doping produces a p-doped polymer in its metallic state. Treatment with a nucleophile (NaOMe) converts the cationic polymer to a neutral, non-conjugated state, allowing the band gap to be tuned chemically, post-polymerization. The synthesis of these materials is carried out entirely without the use of Sn or Pd and relies on scalable Friedel-Crafts chemistry. This journal is the Partner Organisations 2014.
- Voortman, Thomas P.,De Gier, Hilde D.,Havenith, Remco W. A.,Chiechi, Ryan C.
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- A fluorene-based material containing triple azacrown ether groups: Synthesis, characterization and application in chemosensors and electroluminescent devices
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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.
- Wu, Chia-Shing,Lin, Ying-Ju,Chen, Yun
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- Monodisperse fluorene oligomers exhibiting strong dipolar coupling interactions
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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.
- Anemian, Remi,Mulatier, Jean-Christophe,Andraud, Chantal,Stephan, Olivier,Vial, Jean-Claude
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- Supported composite metallocene catalyst, its preparation method and use the catalyst method for preparing polyolefin
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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.
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Paragraph 0119 - 0122
(2017/08/02)
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- A novel fluorene-based aggregation-induced emission (AIE)-active gold(i) complex with crystallization-induced emission enhancement (CIEE) and reversible mechanochromism characteristics
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A new fluorene-based AIE-active gold(i) complex was designed and synthesized. The novel luminogen exhibits a crystallization-induced emission enhancement (CIEE) effect and reversible mechanochromic behavior with fluorescence changes between green and yellow emissions.
- Chen, Zhao,Zhang, Jing,Song, Min,Yin, Jun,Yu, Guang-Ao,Liu, Sheng Hua
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supporting information
p. 326 - 329
(2015/02/19)
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- Synthesis and two-photon absorption properties of star-shaped chromophores derived from functionalized fluorene units
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A set of small star-shaped chromophores composed of three fluorene-based congeners have been synthesized and shown experimentally to possess strong and widely dispersed two-photon absorptivities in the visible to near-IR region under the irradiation of femtosecond and nanosecond laser pulses. In addition, the number of electron-donating fluorenyl units incorporated in the final structure was closely connected to the molecular two-photon activities of these model compounds. Effective optical power attenuation and stabilization behaviors of these dye molecules in the nanosecond time domain were also investigated. The results indicate that such a structural motif could be useful in the molecular design of strong two-photon absorbing material systems for quick-responding and broadband optical suppressing-related applications, particularly for laser pulses with long durations in the near-IR region. A set of star-shaped chromophores containing functionalized fluorene units were synthesized and shown to possess ascending two-photon absorptivities with the growth of their π systems. The observed effective optical power-limiting and stabilization behaviors in the nanosecond time domain indicate that these dye molecules have potential as broadband and quick-responding optical limiters. Copyright
- Lin, Tzu-Chau,Liu, Che-Yu,Huang, Bor-Rong,Lin, Ja-Hon,Shen, Yu-Kai,Wu, Cheng-Yu
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p. 498 - 508
(2013/02/25)
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- Strongly luminescent gold(III) complexes with long-lived excited states: High emission quantum yields, energy up-conversion, and nonlinear optical properties
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Photochemistry: A series of emissive gold(III) complexes with fluorene-containing cyclometalating ligands exhibits strong phosphorescence and long-lived excited states with emission quantum yields and lifetimes up to 58 % and 305 μs, respectively. These c
- To, Wai-Pong,Chan, Kaai Tung,Tong, Glenna So Ming,Ma, Chensheng,Kwok, Wai-Ming,Guan, Xiangguo,Low, Kam-Hung,Che, Chi-Ming
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supporting information
p. 6648 - 6652
(2013/07/26)
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- Selective functionalization of fullerenes with N,N-dihalosulfonamides as an N1 unit: Versatile syntheses of aza[60]fulleroids and aziridino[60]fullerenes and their application to photovoltaic cells
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Highly selective and versatile methods for the synthesis of aza[60]fulleroids and aziridino[60]fullerenes from C60 have been developed. The reactions utilized N,N-dihalosulfonamides as an N1 source. The photophysical, electrochemical
- Nagamachi, Toshiki,Takeda, Youhei,Nakayama, Kazuhisa,Minakata, Satoshi
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supporting information
p. 12035 - 12045
(2012/10/30)
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- METHOD OF PREPARING ETHYLENE-α-OLEFIN-DIENE COPOLYMER
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The present invention relates to a method of preparing an ethylene-α-olefin-diene copolymer and an ethylene-α-olefin-diene copolymer prepared thereby, by using a transition metal compound based on a cyclopenta[b]fluorenyl group as a catalyst.
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Page/Page column 34
(2013/02/27)
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- NEW CYCLOPENTA[B]FLUORENYL TRANSITION METAL COMPOUND, CATALYST COMPOSITION CONTAINING THE SAME, AND METHOD OF PREPARING ETHYLENE HOMOPOLYMER OR COPOLYMER OF ETHYLENE AND α-OLEFIN USING THE SAME
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The present invention relates to a new transition metal compound based on cyclopenta[b]fluorenyl group, a transition metal catalyst composition containing the same and having high catalytic activity for preparing an ethylene homopolymer or a copolymer of ethylene and one α-olefin, a method of preparing an ethylene homopolymer or a copolymer of ethylene and α-olefin using the same, and the prepared ethylene homopolymer or the copolymer of ethylene and α-olefin.
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Page/Page column 35-36
(2013/02/27)
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- Synthesis and characterization of thiophene and fluorene based donor-acceptor conjugated polymer containing 1,3,4-oxadiazole units for light-emitting diodes
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A new donor-acceptor (D-A) conjugated polymer (PDTOF) containing 3,4-didodecyloxythiophene, fluorene and 1,3,4-oxadiazole units is synthesized by using Wittig reaction methodology. The synthesized polymer is characterized by 1H NMR, FTIR, GPC,
- Murali,Naveen,Udayakumar,Yadav, Vandana,Srivastava, Ritu
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supporting information; experimental part
p. 157 - 161
(2012/01/19)
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- Solution-processable and thermally cross-linkable fluorene-cored triple-triphenylamines with terminal vinyl groups to enhance electroluminescence of MEH-PPV: Synthesis, curing, and optoelectronic properties
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This study reports the synthesis, curing, and optoelectronic properties of a solution-processable, thermally cross-linkable electron- and hole-blocking material containing fluorene-core and three periphery N-phenyl-N-(4-vinylphenyl) benzeneamine (FTV). Th
- Wu, Chia-Shing,Yang, Ya-Ju,Fang, Szu-Wen,Chen, Yun
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scheme or table
p. 3875 - 3884
(2012/09/25)
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- Synthesis and optoelectronic properties of a luminescent fluorene derivative containing hole-transporting triphenylamine terminals
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Solution-processable 4,4′,4″-{[9,9-bis(hexyl)-9H-fluorene-2,4, 7-triyl]tri-2,1-ethenediyl}tris(N,N-diphenyl)benzeneamine (TF), consisting of a fluorene core and terminal triphenylamine groups, was synthesized by the Wittig reaction. The characteristics of
- Yang, Hsiang-Fu,Su, Wen-Fen,Chen, Yun
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scheme or table
p. 1219 - 1225
(2011/08/03)
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- Synthesis of diaza-analogue of fluorenone and spirobifluorene
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The effective syntheses of diaza-analogue of fluorenone and spirobifluorene with N=N bond has been conducted with the using of ninhydrin and corresponding acetyl derivatives of arenes. Single-crystal X-ray diffraction of 2-(spirobifluoren-2-yl)-3,4-dizasp
- Wu, Guo-Hong,Liu, Qian-Cai,Tang, Jie
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experimental part
p. 1157 - 1168
(2011/03/22)
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- Synthesis, photophysical and electrophosphorescent properties of fluorene-based platinum(II) complexes
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A series of platinum(II) complexes bearing tridentate cyclometalated C^N^N (C^N^N=6-phenyl-2,2'-bipyridine and π-extended R-C^N^N=3-[6'-(naphthalen-2''- yl)pyridin-2'-yl]isoquinoline) ligands with fluorene units have been synthesised and their photophysic
- Yuen, Mai-Yan,Kui, Steven C. F.,Low, Kam-Hung,Kwok, Chi-Chung,Chui, Stephen Sin-Yin,Ma, Chun-Wah,Zhu, Nianyong,Che, Chi-Ming
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supporting information; experimental part
p. 14131 - 14141
(2011/02/23)
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- Improving the compatibility of fullerene acceptors with fluorene-containing donor-polymers in organic photovoltaic devices
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Fluorene-containing PCBM analogs have been synthesized and tested with a polyfluorene copolymer, PF10TBT, in organic photovoltaic devices resulting in an increase of ～130 mV in the open circuit voltage compared to devices with PCBM as acceptor material.
- Kuhlmann, Jan-Carlos,Bruyn, Paul De,Bouwer, Ricardo K. M.,Meetsma, Auke,Blom, Paul W. M.,Hummelen, Jan C.
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supporting information; experimental part
p. 7232 - 7234
(2010/11/16)
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- Thermally cross-linkable hyperbranched polymers containing triphenylamine moieties: Synthesis, curing and application in light-emitting diodes
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This paper demonstrates synthesis of hyperbranched polymers (HTP and HTPOCH3), containing triphenylamine moieties in main chain and thermally cross-linkable periphery or terminal vinyl groups, and application as hole-transporting layer (HTL) in
- Yu, Juin-Meng,Chen, Yun
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scheme or table
p. 4484 - 4492
(2011/11/12)
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- Synthesis and characterization of 9,9-dialkylfluorene capped benzo[c]thiophene/benzo[c]selenophene analogs as potential OLEDs
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The synthesis of soluble benzo[c]thiophene analogs capped with 9,9-dialkylfluorene at one end is described.
- Mohanakrishnan, Arasambattu K.,Senthil Kumar, Natarajan,Amaladass
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p. 4792 - 4795
(2008/12/22)
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- Method for producing substituted fluorene monomers
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A method for preparing a composition of the formula in a yield greater than 50% where R1 is C 1-20 comprising the steps of combining fluorene or dibromo flourene, an excess of alkali metal hydroxide and a halogenated alkyl in the presence of a phase transfer catalyst but in the absence of a polar aprotic solvent; heating the combination; and separating the dialkylated fluorene or dialylated dibromo fluorene. If the flourene is not brominated prior to alkylation, the dialkylated fluorene is then brominated.
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- Delocalization of positive and negative charge carriers on oligo- and poly-fluorenes studied by low-temperature matrix isolation technique
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Oligofluorenes with well-defined chain length (n = 1-5) have been synthesized by step-by-step Suzuki coupling reaction as the basis sets of conjugated segments in polyfluorenes. Cation and anion radicals of oligofluorenes (n > 2) showed intense and clear
- Koizumi, Yoshiko,Seki, Shu,Acharya, Anjali,Saeki, Akinori,Tagawa, Seiichi
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p. 1290 - 1291
(2007/10/03)
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