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1.
Dr. Hironobu Hayashi Yuki Kato Dr. Akinobu Matsumoto So Shikita Dr. Naoya Aizawa Prof. Dr. Mitsuharu Suzuki Prof. Dr. Naoki Aratani Prof. Dr. Takuma Yasuda Prof. Dr. Hiroko Yamada 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(68):15565-15571
Substituted acene derivatives are regarded as promising materials for organic electronic devices such as organic light-emitting diodes (OLEDs). In particular, anthracene derivatives are known to exhibit good fluorescence property, with the air stability and solubility in common organic solvents expected to give advantages for solution-processed device fabrication. In this study, a series of bistriisopropylsilyl(TIPS)ethynyl anthracene derivatives with azaacene-containing iptycene wings have been synthesized by using condensation reactions. Effects of size of azaacenes on optical properties and packing structures were investigated. UV/Vis absorption and fluorescence spectra indicate that the π-elongation of iptycene units has small effects on the overall π-system, which is also supported by electrochemical measurements. Secondly, single-crystal X-ray analysis implies that the molecules likely have interactions with the iptycene units of adjacent molecules, while the iptycene wings and TIPSethynyl groups can prevent the central anthracene unit from undesirable non-radiative energy loss. Finally, the most emissive derivative was used as a dopant for solution-processed OLEDs, showing obvious electroluminescence with a luminance of over 920 cd m−2. 相似文献
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Maroni Fabio Bruni Pantaleone Suzuki Naoki Aihara Yuichi Croce Fausto 《Journal of Solid State Electrochemistry》2019,23(6):1697-1703
Journal of Solid State Electrochemistry - All-solid-state batteries represent the next generation of electrochemical energy storage systems. A tin-carbon nanocomposite material is prepared by the... 相似文献
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Enhancement of Light Absorption Ability of Synthetic Chlorophyll Derivatives by Conjugation with a Difluoroboron Diketonate Group 下载免费PDF全文
Dr. Yusuke Kinoshita Dr. Yuichi Kitagawa Prof. Dr. Hitoshi Tamiaki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(29):9996-10001
The enhancement of the light absorption ability of synthetic chlorophyll derivatives is demonstrated. Chlorophyll derivatives directly conjugated with a difluoroboron 1,3‐diketonate group at the C3 position were synthesized from methyl pyropheophorbide‐d through Barbier acylmethylation of the C3‐formyl moiety, oxidation of the C3‐carbinol, and difluoroboron complexation of the diketonate. Electronic absorption spectra in a diluted solution showed that the synthetic conjugates gave an absorption band at λ=400–500 nm, with a Qy band shifted to a longer wavelength of λ≈700 nm. DFT calculations demonstrated that the absorption bands and redshifts were ascribable to the coupling of the LUMO of chlorin with that of the difluoroboron diketonate moiety. The introduction of a pyrenyl group at the C33‐position of the conjugate afforded an additional charge‐transfer band over λ=500 nm, producing a pigment that bridged the green gap in standard chlorophylls. 相似文献
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Aromaticity Relocation in Perylene Derivatives upon Two‐Electron Oxidation To Form Anthracene and Phenanthrene 下载免费PDF全文
Akinobu Matsumoto Dr. Mitsuharu Suzuki Dr. Hironobu Hayashi Dr. Daiki Kuzuhara Dr. Junpei Yuasa Prof. Dr. Tsuyoshi Kawai Prof. Dr. Naoki Aratani Prof. Dr. Hiroko Yamada 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(41):14462-14466
We prepared perylene dications 1 2+ and 2 2+ by using “capped” perylene derivatives, and for the first time, successfully obtained single crystals of a perylene dication 1 2+ that enabled us to perform its structural analysis. We realized that the substituted aryl groups on perylene control the positions of positive charges, thus the remaining electronic system satisfies Clar's sextet rule toward the highest number of localized sextets. Experimental and theoretical evidence proved that Clar's aromatic π‐sextet rule could be applied even for the dicationic perylenes in a very simple way. 相似文献
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Inside Cover: Enhancement of Light Absorption Ability of Synthetic Chlorophyll Derivatives by Conjugation with a Difluoroboron Diketonate Group (Chem. Eur. J. 29/2016) 下载免费PDF全文
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Yuki Shintani Taku Ohtomi Dr. Aya Shibata Dr. Yoshiaki Kitamura Koichiro M. Hirosawa Prof. Kenichi G. N. Suzuki Prof. Masato Ikeda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(8):e202104421
Aqueous self-assembly of short peptides has attracted growing attention for the construction of supramolecular materials for various bioapplications. Herein, we describe how the thermolysin-assisted biocatalytic construction of a dipeptide hydrazide from an N-protected amino acid and an amino acid hydrazide leads to the formation of thermally stable supramolecular hydrogels. In addition, we demonstrate the post-assembly modification of the supramolecular architectures constructed in situ tethering hydrazide groups as a chemical handle by means of fluorescence imaging. 相似文献
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Funakawa Daiju Matsuzawa Yasumichi Sasaki Itaru Suzuki Akito Teranishi Noriaki 《Letters in Mathematical Physics》2020,110(9):2471-2490
Letters in Mathematical Physics - We study time operators for discrete-time quantum systems. Quantum walks are typical examples. We construct time operators for one-dimensional homogeneous quantum... 相似文献