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Cyril Poriel - One of the best experts on this subject based on the ideXlab platform.
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A–π–A, D–π–D and D–π–A blue emitting fluorophores based on dispiro[fluorene-9,6′-indeno[1,2-b]fluorene-12′,9′′-fluorene]
Materials Advances, 2021Co-Authors: Damien Thirion, Joëlle Rault-berthelot, Maxime Romain, Cyril PorielAbstract:We report a series of blue fluorophores based on the dispiro[fluorene-9,6′-indeno[1,2-b]fluorene-12′,9′′-fluorene] (DSF-IF) scaffold.
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Universal Host Materials for Red, Green and Blue High-Efficiency Single-Layer Phosphorescent Organic Light-Emitting Diodes
Journal of Materials Chemistry C, 2020Co-Authors: Fabien Lucas, Joëlle Rault-berthelot, Cassandre Quinton, Sadiara Fall, Thomas Heiser, Denis Tondelier, Bernard Geffroy, Nicolas Leclerc, Cyril PorielAbstract:Simplifying the structure of Organic Light-Emitting Diodes (OLEDs) has been for the last twenty years the purpose of many studies. However, despite these efforts, only a few materials provide high efficiency devices. We report herein efficient design strategies to construct universal host materials for red, green and blue Single-Layer Phosphorescent OLEDs (SL-PhOLEDs). The three materials investigated, SPA-2,7-F(POPh2)2, SPA-3,6-F(POPh2)2 and SPA-2-FPOPh2, have been synthesized via an efficient approach and are constructed on the association of an electron rich phenylacridine unit connected by a spiro carbon atom to three different electron-deficient diphenylphosphineoxide-substituted Fluorenes. Electrochemical, spectroscopic, thermal and transport properties are discussed. The position (C2 and C7 vs. C3 and C6) and the number (1 vs. 2) of diphenylphosphineoxide units on the fluorene backbone have been particularly studied to highlight the best combination in term of device performances.
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Violet-to-blue tunable emission of aryl-substituted dispirofluorene-indenofluorene isomers by conformationally-controllable intramolecular excimer formation.
Chemistry - A European Journal, 2011Co-Authors: Cyril Poriel, Rémi Métivier, Joëlle Rault-berthelot, Frédéric Barrière, Olivier JeanninAbstract:Two series of DiSpiroFluorene-IndenoFluorene (DSF-IF) positional isomers, namely dispiro[2,7-diarylfluorene-9',6,9'',12-indeno[1,2-b]Fluorenes], (1,2-b)-DSF-IFs 1 and dispiro[2,7-diarylfluorene-9',6,9'',12-indeno[2,1-a]Fluorenes], (2,1-a)-DSF-IFs 2 have been synthesized. These violet-to-blue fluorescent emitters possess a 3π-2spiro architecture, which combines via two spiro links two different indenofluorene cores, that is, (1,2-b)-IF or (2,1-a)-IF and 2,7-substituted-diaryl-fluorene units. Due to their different geometric profiles, the two families of positional isomers present drastically different properties. The marked difference observed between the properties of (1,2-b)-DSF-IF (1) and (2,1-a)-DSF-IF (2) is discussed in terms of intramolecular π-π interactions occurring in (2,1-a)-DSF-IF (2) leading to conformationally-controllable intramolecular excimer formation. Indeed, the original geometry of the (2,1-a)-DSF-IF (2) family, with face-to-face "aryl-fluorene-aryl" moieties, leads to remarkable excimer emission through intramolecular π-π interactions in the excited state. Furthermore, the emission wavelengths can be gradually modulated by the control of the steric hindrance between the adjacent substituted phenyl rings. Thus, through a comparative and detailed study of the (1)H NMR, electrochemical and photophysical properties of DSF-IFs 1 and 2, we have evidenced the intramolecular π-π interactions occurring between the two "aryl-fluorene-aryl" moieties in the ground state and in the excited state. These properties have been finally correlated to the spectacular conformational change modeled by density functional theory (DFT) calculations. Indeed, the two "aryl-fluorene-aryl" moieties switch from a staggered conformation in the ground state to an eclipsed conformation in the first excited state.
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Dispirofluorene-indenofluorene derivatives as new building blocks for blue organic electroluminescent devices and electroactive polymers.
Chemistry - A European Journal, 2007Co-Authors: Cyril Poriel, David Horhant, Jing-jing Liang, Morgane Virboul, Gilles Alcaraz, Joëlle Rault-berthelot, Frédéric Barrière, Nicolas Cocherel, Alexandra L. Z. Slawin, Nathalie AudebrandAbstract:A series of new dispiro[fluorene-9',6,9'',12-indeno[1,2b]Fluorenes] (DSF-IFs) has been synthesised. These new building blocks for blue-light-emitting devices and electroactive polymers combine indenofluorene (IF) and spirobifluorene (SBF) properties. We report here our synthetic investigations towards these new structures and their thermal, structural, photophysical and electrochemical properties. These properties have been compared to those of IF and SBF. We also report the anodic oxidation of DSF-IFs that leads to the formation of non-soluble transparent three-dimensional polymers. The structural and electrochemical behaviour of these polymers has been studied. The first application of these building blocks as new blue-light-emitting materials in organic light-emitting diodes (OLED) is also reported.
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Dispirofluorene-indenofluorene (DSFIF): Synthesis, Electrochemical, and Optical Properties of a Promising New Family of Luminescent Materials
Organic Letters, 2006Co-Authors: David Horhant, Jing-jing Liang, Morgane Virboul, Cyril Poriel, Gilles Alcaraz, Joe 1lle Rault-berthelotAbstract:A series of new dispiro[fluorene-9′,6,9′′,12-indeno[1,2b]Fluorenes] (DSFIFs) that combine indenofluorene (IF) and spirobifluorene (SBF) architectural specificities have been prepared. Their anodic oxidations lead to the formation of nonsoluble transparent polymers. The photophysical and electrochemical properties of these new molecules have been evaluated for further blue OLED applications. Poly-2,7-(9,9-dialkyl)Fluorenes (PFs) and copolymers are among the most promising blue light emitting materials despite the problem of their long-term color stability.
Joëlle Rault-berthelot - One of the best experts on this subject based on the ideXlab platform.
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A–π–A, D–π–D and D–π–A blue emitting fluorophores based on dispiro[fluorene-9,6′-indeno[1,2-b]fluorene-12′,9′′-fluorene]
Materials Advances, 2021Co-Authors: Damien Thirion, Joëlle Rault-berthelot, Maxime Romain, Cyril PorielAbstract:We report a series of blue fluorophores based on the dispiro[fluorene-9,6′-indeno[1,2-b]fluorene-12′,9′′-fluorene] (DSF-IF) scaffold.
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Universal Host Materials for Red, Green and Blue High-Efficiency Single-Layer Phosphorescent Organic Light-Emitting Diodes
Journal of Materials Chemistry C, 2020Co-Authors: Fabien Lucas, Joëlle Rault-berthelot, Cassandre Quinton, Sadiara Fall, Thomas Heiser, Denis Tondelier, Bernard Geffroy, Nicolas Leclerc, Cyril PorielAbstract:Simplifying the structure of Organic Light-Emitting Diodes (OLEDs) has been for the last twenty years the purpose of many studies. However, despite these efforts, only a few materials provide high efficiency devices. We report herein efficient design strategies to construct universal host materials for red, green and blue Single-Layer Phosphorescent OLEDs (SL-PhOLEDs). The three materials investigated, SPA-2,7-F(POPh2)2, SPA-3,6-F(POPh2)2 and SPA-2-FPOPh2, have been synthesized via an efficient approach and are constructed on the association of an electron rich phenylacridine unit connected by a spiro carbon atom to three different electron-deficient diphenylphosphineoxide-substituted Fluorenes. Electrochemical, spectroscopic, thermal and transport properties are discussed. The position (C2 and C7 vs. C3 and C6) and the number (1 vs. 2) of diphenylphosphineoxide units on the fluorene backbone have been particularly studied to highlight the best combination in term of device performances.
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Violet-to-blue tunable emission of aryl-substituted dispirofluorene-indenofluorene isomers by conformationally-controllable intramolecular excimer formation.
Chemistry - A European Journal, 2011Co-Authors: Cyril Poriel, Rémi Métivier, Joëlle Rault-berthelot, Frédéric Barrière, Olivier JeanninAbstract:Two series of DiSpiroFluorene-IndenoFluorene (DSF-IF) positional isomers, namely dispiro[2,7-diarylfluorene-9',6,9'',12-indeno[1,2-b]Fluorenes], (1,2-b)-DSF-IFs 1 and dispiro[2,7-diarylfluorene-9',6,9'',12-indeno[2,1-a]Fluorenes], (2,1-a)-DSF-IFs 2 have been synthesized. These violet-to-blue fluorescent emitters possess a 3π-2spiro architecture, which combines via two spiro links two different indenofluorene cores, that is, (1,2-b)-IF or (2,1-a)-IF and 2,7-substituted-diaryl-fluorene units. Due to their different geometric profiles, the two families of positional isomers present drastically different properties. The marked difference observed between the properties of (1,2-b)-DSF-IF (1) and (2,1-a)-DSF-IF (2) is discussed in terms of intramolecular π-π interactions occurring in (2,1-a)-DSF-IF (2) leading to conformationally-controllable intramolecular excimer formation. Indeed, the original geometry of the (2,1-a)-DSF-IF (2) family, with face-to-face "aryl-fluorene-aryl" moieties, leads to remarkable excimer emission through intramolecular π-π interactions in the excited state. Furthermore, the emission wavelengths can be gradually modulated by the control of the steric hindrance between the adjacent substituted phenyl rings. Thus, through a comparative and detailed study of the (1)H NMR, electrochemical and photophysical properties of DSF-IFs 1 and 2, we have evidenced the intramolecular π-π interactions occurring between the two "aryl-fluorene-aryl" moieties in the ground state and in the excited state. These properties have been finally correlated to the spectacular conformational change modeled by density functional theory (DFT) calculations. Indeed, the two "aryl-fluorene-aryl" moieties switch from a staggered conformation in the ground state to an eclipsed conformation in the first excited state.
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Dispirofluorene-indenofluorene derivatives as new building blocks for blue organic electroluminescent devices and electroactive polymers.
Chemistry - A European Journal, 2007Co-Authors: Cyril Poriel, David Horhant, Jing-jing Liang, Morgane Virboul, Gilles Alcaraz, Joëlle Rault-berthelot, Frédéric Barrière, Nicolas Cocherel, Alexandra L. Z. Slawin, Nathalie AudebrandAbstract:A series of new dispiro[fluorene-9',6,9'',12-indeno[1,2b]Fluorenes] (DSF-IFs) has been synthesised. These new building blocks for blue-light-emitting devices and electroactive polymers combine indenofluorene (IF) and spirobifluorene (SBF) properties. We report here our synthetic investigations towards these new structures and their thermal, structural, photophysical and electrochemical properties. These properties have been compared to those of IF and SBF. We also report the anodic oxidation of DSF-IFs that leads to the formation of non-soluble transparent three-dimensional polymers. The structural and electrochemical behaviour of these polymers has been studied. The first application of these building blocks as new blue-light-emitting materials in organic light-emitting diodes (OLED) is also reported.
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Comparative Study of the Oxidation of Fluorene and 9,9-Disubstituted Fluorenes and Their Related 2,7‘-Dimers and Trimer
Chemistry of Materials, 2005Co-Authors: Philippe Hapiot, Corinne Lagrost, Fabien Le Floch, E. Raoult, Joëlle Rault-berthelotAbstract:Electroactive polyfluorene films were obtained by anodic coupling of fluorene and a series of 9,9-disubstituted Fluorenes and their related 2,7‘-dimers and trimer. The polymerization mechanism is discussed in light of cyclic voltammetry investigations in organic media using the classical millimetric electrode and ultramicroelectrodes, DFT theoretical calculations, and laser flash photolysis experiments. The first step of electropolymerization involves the formation of the carbon−carbon bond through the coupling between two fluorene radical cations. However, the radical cation of the produced dimer is not reactive enough to repeat the coupling reaction as in the classical electropolymerization mechanism. To continue the polymerization, formation of a higher oxidation state is required. This behavior is supported by theoretical expectations.
Phil Ho Lee - One of the best experts on this subject based on the ideXlab platform.
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synthesis of Fluorenes via tandem copper catalyzed 3 2 cycloaddition and rhodium catalyzed denitrogenative cyclization in a 5 exo mode from 2 ethynylbiaryls and n sulfonyl azides in one pot
Journal of Organic Chemistry, 2015Co-Authors: Boram Seo, Woo Hyung Jeon, Jaeeun Kim, Sunghwa Kim, Phil Ho LeeAbstract:An efficient synthetic method of Fluorenes having an enamine moiety at C-9 methylene bridge is developed from N-sulfonyl-4-biaryl-1,2,3-triazole derivatives via Rh-catalyzed denitrogenative cyclization in a 5-exo mode. Rh-catalyzed denitrogenative cyclization followed by catalytic hydrogenation produces N-tosylaminomethyl-substituted Fluorenes in one pot. Moreover, Fluorenes are synthesized via tandem Cu-catalyzed [3 + 2] cycloaddition and Rh-catalyzed denitrogenative cyclization in a 5-exo mode starting from 2-ethynylbiaryls and N-sulfonyl azides in one pot.
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Synthesis of Fluorenes via Tandem Copper-Catalyzed [3 + 2] Cycloaddition and Rhodium-Catalyzed Denitrogenative Cyclization in a 5-Exo Mode from 2‑Ethynylbiaryls and N‑Sulfonyl Azides in One Pot
2015Co-Authors: Boram Seo, Woo Hyung Jeon, Jaeeun Kim, Sunghwa Kim, Phil Ho LeeAbstract:An efficient synthetic method of Fluorenes having an enamine moiety at C-9 methylene bridge is developed from N-sulfonyl-4-biaryl-1,2,3-triazole derivatives via Rh-catalyzed denitrogenative cyclization in a 5-exo mode. Rh-catalyzed denitrogenative cyclization followed by catalytic hydrogenation produces N-tosylaminomethyl-substituted Fluorenes in one pot. Moreover, Fluorenes are synthesized via tandem Cu-catalyzed [3 + 2] cycloaddition and Rh-catalyzed denitrogenative cyclization in a 5-exo mode starting from 2-ethynylbiaryls and N-sulfonyl azides in one pot
Myoung-seon Gong - One of the best experts on this subject based on the ideXlab platform.
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Deep blue fluorescent host materials based on spirobenzofluorene-fluorene dimers and their properties
Dyes and Pigments, 2013Co-Authors: Chil Won Lee, Ji-geun Jang, Myoung-seon GongAbstract:Abstract Deep blue fluorescent host materials based on the novel spiro[benzo[ c ]fluorene-7,9′-fluorene] dimers, 5-[spiro[benzo[ c ]fluorene-7,9′-fluoren]-5-yl] spiro[benzo[ c ]fluorene-7,9′-fluorene], 9-[spiro[benzo[ c ]fluorene-7,9′-fluoren]-2′-yl] spiro[benzo[ c ]fluorene-7,9′-fluorene], and 1,4-bis(spiro[benzo[ c ]fluorene-7,9′-fluorene]-5-yl)benzene were designed and successfully prepared using the Suzuki coupling reaction. The physical properties of the sprodimers and their electroluminescent characteristics as blue host materials doped with N,N,N′,N′ -tetraphenylspiro[benzo[c]fluorene-7,9′-fluorene]-5,9-diamine were investigated. The device configuration used was ITO/ N,N′ -diphenyl- N,N′ -bis[4-(phenyl- m -tolyl-amino)phenyl]biphenyl-4,4′-diamine/ N,N′ -di(1-naphthyl)- N,N′ -diphenylbenzidine/host:5% dopant/tris(8-hydroxyquinoline)aluminum)/LiF. The device obtained from 1,4-bis(spiro[benzo[ c ]fluorene-7,9′-fluorene]-5-yl)benzene doped with N,N,N′,N′ -tetraphenylspiro[benzo[ c ]fluorene-7,9′-fluorene]-5,9-diamine showed a high color purity of (0.146 and 0.148), efficiency of 7.44 cd A −1 and an external quantum efficiency of 5.60% at 7 V.
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Deep Blue Fluorescent Host Materials Based on a Novel Spiro(benzo(c)fluorene-7,9'-fluorene) Core Structure with Side Aromatic Wings
Bulletin of the Korean Chemical Society, 2012Co-Authors: In-ho Lee, Jeong-a Seo, Myoung-seon GongAbstract:E-mail: msgong@dankook.ac.krReceived March 24, 2012, Accepted April 9, 2012Deep blue fluorescent host materials based on a novel spiro[benzo[ c]fluorene-7,9'-fluorene] core structure withside aromatic wings in the 5- and 9-positions, namely, 5,9-di(naphthalen-2-yl)spiro[benzo[c]fluorene-7,9'-fluorene] (DN-SBFF), 5,9-bis(4-t-butylphenyl)spiro[benzo[ c]fluorene-7,9'-fluorene] (BP-SBFF), and 5,9-bis(4-fluorophenyl)spiro[benzo[ c]fluorene-7,9'-fluorene] (FP-SBFF), were designed and successfully pre-pared using the Suzuki reaction. The physical properties of these materials and their EL characteristics as bluehost materials doped with N,N,N',N'-tetraphenylspiro[benzo[c]fluorene-7,9'-fluorene]-5,9-diamine ( TPA-SBFF)were investigated. The device used comprised ITO/ N,N'-diphenyl-N,N'-bis[4-(phenyl-m-tolyl-amino)phenyl]-biphenyl-4,4'-diamine (DNTPD)/N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine (NPB)/(FP-SBFF):dopant x%/tris(8-hydroxyquinoline)aluminum (Alq
P J Chapman - One of the best experts on this subject based on the ideXlab platform.
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Transformation of substituted Fluorenes and fluorene analogs by Pseudomonas sp. strain F274
Applied and environmental microbiology, 1995Co-Authors: Magdalena Grifoll, S A Selifonov, P J ChapmanAbstract:Pseudomonas sp. strain F274, previously shown to catabolize fluorene via fluorenone and its angular dioxygenation, 2(prm1),3(prm1)-dihydroxy-2-carboxybiphenyl, phthalate, and protocatechuate, was examined for its ability to transform substituted Fluorenes and S- and N-heterocyclic analogs. Halogen- and methyl-substituted Fluorenes were metabolized to correspondingly substituted phthalates via attack on the unsubstituted ring. In the case of 1-methylfluorene, initial oxidation of the methyl group to carboxyl prevented all other transformations but 9-monooxygenation. This strain also oxidized the S-heteroatoms and benzylic methylenic groups of fluorene analogs. No angular dioxygenation of S- and N-heterocycles was observed.
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Evidence for a novel pathway in the degradation of fluorene by Pseudomonas sp. strain F274
Applied and environmental microbiology, 1994Co-Authors: Magdalena Grifoll, S A Selifonov, P J ChapmanAbstract:A fluorene-utilizing microorganism, identified as a species of Pseudomonas, was isolated from soil severely contaminated from creosote use and was shown to accumulate six major metabolites from fluorene in washed-cell incubations. Five of these products were identified as 9-fluorenol, 9-fluorenone, (+)-1,1a-dihydroxy-1-hydro-9-fluorenone, 8-hydroxy-3,4-benzocoumarin, and phthalic acid. This last compound was also identified in growing cultures supported by fluorene. Fluorene assimilation into cell biomass was estimated to be approximately 50%. The structures of accumulated products indicate that a previously undescribed pathway of fluorene catabolism is employed by Pseudomonas sp. strain F274. This pathway involves oxygenation of fluorene at C-9 to give 9-fluorenol, which is then dehydrogenated to the corresponding ketone, 9-fluorenone. Dioxygenase attack on 9-fluorenone adjacent to the carbonyl group gives an angular diol, 1,1a-dihydroxy-1-hydro-9-fluorenone. Identification of 8-hydroxy-3,4-benzocoumarin and phthalic acid suggests that the five-membered ring of the angular diol is opened first and that the resulting 29-carboxy derivative of 2,3-dihydroxy-biphenyl is catabolized by reactions analogous to those of biphenyl degradation, leading to the formation of phthalic acid. Cell extracts of fluorene-grown cells possessed high levels of an enzyme characteristic of phthalate catabolism, 4,5-dihydroxyphthalate decarboxylase, together with protocatechuate 4,5-dioxygenase. On the basis of these findings, a pathway of fluorene degradation is proposed to account for its conversion to intermediary metabolites. A range of compounds with structures similar to that of fluorene was acted on by fluorene-grown cells to give products consistent with the initial reactions proposed.
