- Harvesting of organic triplet emissions in metal diynes and polyynes of group 10-12 transition elements containing the conjugation-interrupting diphenylfluorene unit
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Soluble and thermally stable group 10 platinum(II) and group 12 mercury(II) polyyne polymers containing the diphenylfluorene moiety trans-[-Pt(PBu 3)2C≡CRC≡C-]n and [-HgC≡CRC≡ C-]n (R = 9,9-diphenylfluorene) were prepared in good yields by polycondensation polymerization of trans[PtCl 2(PBu3)2] or HgCl2 with 9,9-bis(4-ethynylphenyl)fluorene. We report the optical absorption and photoluminescence spectra of these carbon-rich metal-based polymers and compare the results with their monomeric model complexes trans-[Pt(Ph)(PEt 3)2C≡CRC≡CPt(Ph)(PEt3) 2] and [MeHgC≡CRC≡CHgMe] as well as the group 11 gold(I) congener [(PPh3)AuC≡CRC≡CAu(PPh3)]. The regiochemical structures of the polymers were studied by NMR spectroscopy and by single-crystal X-ray analysis for the model platinum(II) compound. Our investigations indicate that harvesting of the organic triplet emissions can be achieved by the heavy-atom effect of group 10-12 transition metals (i.e., Pt, Au, Hg) which enables a very high efficiency of intersystem crossing from the S1 singlet excited state to the T1 triplet excited state. The influence of the metal and the fluorene ring on the intersystem crossing rate and the spatial extent of singlet and triplet excitons is characterized. These phosphorescent metal-organic materials show T1-S0 gaps of 2.5 eV or above, which correspond to S1-S0 gaps of 3.1 eV or higher. The present work indicates that high-energy triplet states (and concurrently high optical gaps) intrinsically lead to more efficient phosphorescence in metal-containing aryleneethynylenes and can facilitate the radiative decay pathway.
- Wong, Wai-Yeung,Liu, Li,Poon, Suk-Yue,Choi, Ka-Ho,Cheah, Kok-Wai,Shi, Jian-Xin
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- Synthesis of Primitive Dendrimer Systems Bearing Bicyclo[3,2,0]Hept-6-en-6-yl Groups via Unique Au-catalyzed [2+2] Cyclization
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Propargylic pivaloates bearing an alkynyl group at a three-carbon tether under the gold catalysis would undergo [3,3] rearrangements of propargylic pivaloates followed by tandem [2+2] cyclization to give the corresponding 6-acylbicyclo[3,2,0]hept-6-ens. In continuing work, we prepared various substrates bearing two arms of alkyne-propargylic pivaloates to explore primitive dendrimer concept bicyclic compounds. Finally, we could obtain a series of diasteromeric compounds bearing two arms of 6-acylbicyclo[3,2,0]hept-6-ene groups in high yields.
- Lee, Kyu Hwan,Jillella, Raveendra,Kim, Jaewoong,Oh, Chang Ho
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p. 651 - 656
(2018/04/30)
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- SPIROCYCLIC DERIVATIVE, AND POLYMER, MIXTURE, FORMULATION AND ORGANIC ELECTRONIC DEVICE COMPRISING THE SAME
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Provided are a spirocyclic derivative, and a high polymer, a mixture, a composition and an organic electronic device containing same, wherein in the spirocyclic derivative, two spirocyclic units are directly or indirectly connected by a sp3 hybridized carbon atom, thus effectively adjusting the energy level of the compound, and being beneficial for improving the photoelectric performance of the compound and the stability of the device. An effective solution is provided for effectively reducing the manufacturing cost and improving the efficiency and lifetime of a light-emitting device.
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Paragraph 0177; 0184; 0185
(2019/01/04)
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- Fluorene-containing organic compound and application thereof on OLED (organic light emitting diode) device
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The invention discloses a fluorene-containing organic compound and an application thereof on an OLED (organic light emitting diode) device. The organic compound has the structure shown in the generalformula (1). The compound has higher glass transition temperature and molecular heat stability, proper HOMO and LUMO energy levels and higher Eg, the photoelectric property of an OLED device can be effectively improved and the service life of the OLED device can be effectively prolonged through structure optimization of the device.
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Paragraph 0083; 0084; 0085; 0088
(2018/04/21)
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- Fluorene-based phosphine oxide host materials for blue electrophosphorescence: An effective strategy for a high triplet energy level
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A bolt from the blue! Two novel host materials for blue electrophosphorescence were designed and synthesized by modification of fluorene at the 9-position with diphenylphosphine oxide to give high triplet energy levels of 2.99 eV (see scheme), achieved through an indirect linkage of the chromophore and the phosphine oxide moieties. These host materials were also found to exhibit high thermal and morphological stabilities and efficient energy transfer.
- Yu, Donghui,Zhao, Yongbiao,Xu, Hui,Han, Chunmiao,Ma, Dongge,Deng, Zhaopeng,Gao, Shan,Yan, Pengfei
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p. 2592 - 2596
(2011/04/12)
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- AROMATIC CARBOXYLIC ACID AND METHOD FOR SYNTHESIZING THE SAME
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PROBLEM TO BE SOLVED: To provide a new aromatic carboxylic acid useful as an intermediate raw material of a condensation polymer having a high heat resistance. SOLUTION: This aromatic carboxylic acid is expressed by general formula (1) [wherein, Z is a divalent group expressed by formula (2) or (3) (wherein, X is a halogen)]. The method for producing the aromatic carboxylic acid expressed by general formula (1) and obtained by a halogenation treatment is also provided.
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Page/Page column 8-9
(2010/02/11)
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- Anodic oxidation of novel hole-transporting materials derived from tetraarylbenzidines. Electrochemical and spectroscopic characterization
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Fluorenylidene-linked triarylamines, potential hole-transporting materials, have been prepared by the palladium-catalyzed Hartwig-Buchwald animation. Their redox and spectral properties were investigated in solution, applying cyclic voltammetry, UV-VIS and WR spectroscopy, and in situ spectroelectrochemical measurements. N,N,N′,N′-Tetraphenylbenzidine (1), N,N′-di(1-naphthyl)-N,N′-diphenylbenzidine (2), and triphenylamine (3) served as model substances in the study of the synthesized complex compounds 4 and S. In structure 4, two triphenylamine centres are linked with a non-conjugated fluorene bridge; in structure 5, two tetraarylbenzidine skeletons with two nitrogens are linked with a conjugated biphenyl-bridge system. In addition, structure 5 contains a non-conjugated fluorene bridge. The presence of the fluorene moiety in the molecular design has a significant influence on the investigated properties of the new materials. In the anodic oxidation of the tetraarylbenzidine-type compounds (1, 2, and 5), two well-defined reversible oxidation peaks were observed. However, the oxidation of the triphenylamine-type structures (3 and 4) is more complex, due to fast consecutive reactions. The dimer-like structures (4 and 5) are characterized by two independent oxidation centres that are simultaneously oxidized at approximately the same potentials. This was confirmed by quantitative cyclovoltammetric as well as UV-VIS investigations.
- Faber, Rene,Mielke, G. Felix,Rapta, Peter,Stasko, Andrej,Nuyken, Oskar
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p. 1403 - 1418
(2007/10/03)
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- Structure-Property Relationships in Trimethylenemethane-Type Biradicals. 2. Synthesis and EPR Spectral Characterization of Dinitroxide Biradicals
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Several trimethylenemethane-type (TMM-type) dinitroxide biradicals have been prepared that differ in tert-butylaminoxylphenyl ring torsion angles by virtue of different steric demands of their "spin-protecting groups". In addition, the synthesis of a TMM-type dinitroxide having a planar π-system is reported. The synthetic route employed for the planar TMM-type biradical is general and should therefore expand the utility of TMM-type biradicals that are susceptible to bond torsions that attenuate exchange coupling. The compounds presented are designed to be effective to map out J-coupling/conformation space in TMM-type biradicals. EPR spectroscopic parameters (hfcc and D-values) were compared to determine if their values reflected differences in conformation in the series of biradicals. Interestingly, neither N- nor H-hfcc varied within our series of biradicals/ monoradicals in a regular fashion, indicating that there is no apparent relationship between N- or H-hfcc and conformation (as judged by molecular mechanics calculations). However, D-values, estimated from relative intensities of Δms = 1 and Δms = 2 transitions, are consistent with a varied degree of delocalization in the dinitroxides: smaller D-values for biradicals having smaller aryl torsions (and greater delocalization), and larger D-values for dinitroxides having greater aryl torsions (and less delocalization). All the biradicals studied, except 5, exhibited linear Curie plots. The linear Curie plots are consistent with both triplet ground-states and singlet-triplet degeneracies. Interestingly, dinitroxide 6 exhibited a linear Curie plot, despite the lack of a π-coupling fragment. Biradical 5, however, is a ground-state singlet species with the triplet lying about 140 cal/mol above the singlet.
- Shultz, David A.,Boal, Andrew K.,Lee, Hyoyoung,Farmer, Gary T.
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p. 4386 - 4396
(2007/10/03)
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