- A simple and broadly applicable synthesis of fluorene-coupled D-σ-A type molecules: towards high-triplet-energy bipolar hosts for efficient blue thermally-activated delayed fluorescence
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An effective two-step synthesis of high-triplet-energy (ET) bipolar hosts that is simple and broadly applicable is introduced. Electron-donating (D = (9-phenyl-9H-carbazol-3-yl/4-(9H-carbazol-9-yl)phenyl)) and -accepting (A = (tetrafluoropyridin-4-yl/4,6-diphenyl-1,3,5-triazin-2-yl)) units have been coupled to the C9 atom of fluorene to afford the four hosts 3CzFTFP, 9PhFTFP, 3CzFDPhTz, and 9PhFDPhTz with sp3 C9-centered bulky ternary structures, excellent thermal/morphological stabilities, tunable abilities for bipolar charge carrier injection/transport, and identical high ET (2.87 eV). Blue thermally-activated delayed fluorescence (TADF) devices using these new hosts and 2CzPN as the host-guest system exhibited efficient electroluminescence efficiencies of 38 cd A-1/30 lm W-1/17%, which are among the best for 2CzPN-based TADF devices. The generality of this synthetic strategy to high-ET fluorene-coupled D-σ-A type hosts was confirmed by successfully appending other D/A groups ((diphenylamino)phenyl/phenylsulfonyl) to fluorene, affording TPAFBSO.
- Li, Chuan,Du, Xiaoyang,Zhou, Yu,Ye, Jun,Fu, Lulu,Humphrey, Mark G.,Wu, Chao,Zhao, Juewen,Du, Yanqing,Tao, Silu,Wu, Jiacheng,Zhang, Chi
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Read Online
- Synthesis of 9-biarylfluorenes by one-pot, three-step reactions of N-tosylhydrazones, p-bromobenzeneboronic acid, and arylboronic acids
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A one-pot, three-step reaction of N-tosylhydrazones, p-bromobenzeneboronic acid, and arylboronic acids is established for the synthesis of 9-biarylfluorenes. Sequential formation of Csp3–Csp2 bond and Csp2–Csp2
- He, Jing,Zhang, Jie,Dai, Bin,Liu, Ping
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p. 268 - 273
(2019/07/15)
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- Lewis Acid Catalyzed [4 + 2] Cycloaddition of N-Tosylhydrazones with ortho-Quinone Methides
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A formal [4 + 2] cycloaddition of N-tosylhydrazones with ortho-quinone methides was developed, affording the facile synthesis of diverse 1,3-oxazine derivatives under mild conditions. In this transformation, N-tosylhydrazones are used as a 1,2-dipole synt
- Wang, Chun-Ying,Han, Jia-Bin,Wang, Long,Tang, Xiang-Ying
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p. 14258 - 14269
(2019/11/11)
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- Organic electro-luminescent material and organic light emitting device thereof
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The invention provides an organic electro-luminescent material and an organic light emitting device thereof, relating to the technical field of organic photoelectric materials. The organic electro-luminescent material contains fluorene that is different f
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Paragraph 0070; 0071; 0072
(2018/04/03)
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- Directed C-C bond cleavage of a cyclopropane intermediate generated from: N -tosylhydrazones and stable enaminones: Expedient synthesis of functionalized 1,4-ketoaldehydes
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An efficient method to construct functionalized 1,4-ketoaldehydes bearing all-carbon α-quaternary centers via regioselective C-C bond activation has been described. The cyclopropanation of bench-stable enaminones with in situ generated diazo reagents from
- Ni, Meiyan,Zhang, Jianguo,Liang, Xiaoyu,Jiang, Yaojia,Loh, Teck-Peng
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supporting information
p. 12286 - 12289
(2017/11/20)
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- Copper(I)-Catalyzed Alkylation of Polyfluoroarenes through Direct C - H Bond Functionalization
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The copper(I)-catalyzed alkylation of electron-deficient polyfluoroarenes with N-tosylhydrazones and diazo compounds has been developed. This reaction uses readily available starting materials and is operationally simple, thus representing a practical method for the construction of C(sp2) - C(sp3) bonds with polyfluoroarenes through direct C - H bond functionalization. Mechanistically, copper(I) carbene formation and subsequent migratory insertion are proposed as the key steps in the reaction pathway.
- Xu, Shuai,Wu, Guojiao,Ye, Fei,Wang, Xi,Li, Huan,Zhao, Xia,Zhang, Yan,Wang, Jianbo
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supporting information
p. 4669 - 4672
(2015/04/14)
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- A simple and efficient synthesis of 9-arylfluorenes via metal-free reductive coupling of arylboronic acids and N-tosylhydrazones in situ
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A general, yet efficient synthesis method of 9-arylfluorenes via metal-free reductive coupling of N-tosylhydrazones and arylboronic acids has been developed. This methodology is realized by a one-pot protocol in two steps involving the preparation of N-tosylhydrazones by reacting tosylhydrazide with 9-fluorenone derivatives, followed by the reductive coupling of arylboronic acid in the presence of potassium carbonate to afford various 9-arylfluorenes analogues in moderate to excellent yields. Importantly, the catalytic system presented here enables the use of easily accessible starting materials and can be employed on a wide variety of substrates with good functional group tolerance. This protocol could also be particularly useful for the synthesis of 9-fluorenyl-substituted carbazolyl compounds.
- Shen, Xu,Gu, Ningning,Liu, Ping,Ma, Xiaowei,Xie, Jianwei,Liu, Yan,He, Lin,Dai, Bin
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p. 63726 - 63731
(2015/08/11)
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- N-Tosylhydrazine-mediated deoxygenative hydrogenation of aldehydes and ketones catalyzed by Pd/C
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A mild and efficient method for the deoxygenative hydrogenation of aldehydes and ketones has been developed. The reaction is mediated by N-tosylhydrazine with H2 (1 atm) as the reductant and 10% Pd/C as the catalyst.
- Zhou, Lei,Liu, Zhenxing,Liu, Yizhou,Zhang, Yan,Wang, Jianbo
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p. 6083 - 6087
(2013/07/25)
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- Copper-catalyzed nitrogen loss of sulfonylhydrazones: A reductive strategy for the synthesis of sulfones from carbonyl compounds
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Figure Presented. An efficient method for the synthesis of sulfones via nitrogen loss of sulfonyl hydrazones is described. The reaction was performed in the presence of simple copper salt and base by utilization of sulfonyl hydrazones, which were easily p
- Feng, Xing-Wen,Wang, Jian,Zhang, Ji,Yang, Jing,Wang, Na,Yu, Xiao-Qi
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supporting information; experimental part
p. 4408 - 4411
(2010/12/19)
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- CATALYSTS FOR METATHESIS REACTIONS
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Novel catalysts for metathesis reactions, in particular for the metathesis of nitrile rubber, are provided.
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Page/Page column 15
(2009/04/24)
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- Mimicking the biological activity of diazobenzo[b]fluorene natural products with electronically tuned diazofluorene analogs
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Under appropriate electronic modulation, simple diazofluorene analogs recapitulate the DNA cleavage activity of kinamycin D under thiol-based reducing conditions. Achieving DNA cleavage under these reducing conditions is key to anticancer activity, as the most active compound, 1-methoxydiazofluorene, inhibits the proliferation of HeLa cells.
- Zeng, Wei,Eric Ballard,Tkachenko, Alexander G.,Burns, Virginia A.,Feldheim, Daniel L.,Melander, Christian
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p. 5148 - 5151
(2007/10/03)
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- The Electrochemical Reduction of Fluorenone Tosylhydrazone: Evidence Consistent with Formation of the Tosyl Nitrene Anion Radical
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Fluorenone tosylhydrazone (Fl=NNHTs) undergoes one-electron reductive dehydrogenation in DMF-0.1 F (n-Bu)4NClO4 to give hydrogen and its conjugate base Fl=NN-Ts as products.Fl=NN-Ts is subsequently reduced at more negative potential to a dianion radical (Fl=NNTs dianion radical) that is stable on the cyclic voltammetric time scale.On the coulometric time scale or in the presence of added proton donors (pKa ca.29), Fl=NNTs dianion radical decomposes to give FlHNH2 and TsNH2 as the principal products.A pathway is proposed for the reaction of Fl=NNTs dianion radical which involves rate-determining proton abstraction by the nitrogen atom α to the fluorene moiety.Cyclic voltammetric and chronoamperometric data are presented which are consistent with the formation of the tosyl nitrene anion radical as a short-lived, unobserved intermediate.
- Galen, Dean A. Van,Barnes, James H.,Hawley, M. Dale
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p. 2544 - 2550
(2007/10/02)
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