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21.
Iori Inoue Dr. Koji Yamamoto Prof. Dr. Shigeyoshi Sakaki Prof. Dr. Tetsuro Murahashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(41):10558-10562
A heterometallic M−M′ bond formation is a key to construct atomically precise bimetallic clusters and materials. However, it is sometimes not straightforward to construct a heterometallic M−M′ bond through conventional methods including redox condensation. Here, we found that a sandwich framework of π-conjugated unsaturated hydrocarbon ligands provides a unique coordination environment that facilitates unusual coupling of d8 RhI and d10 M0 (M=Pd, Pt). The molecular orbital analysis showed that the electron-accepting ability of the sandwich framework through back-donation allows the formation of a dσ-type Rh−Pd bond in a (d–d)18 electron system. 相似文献
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Dr. Teng Zhang Dr. Yuichi Kitagawa Ryoma Moriake Pedro Paulo Ferreira da Rosa Dr. Md. Jahidul Islam Dr. Tomoki Yoneda Prof. Yasuhide Inokuma Dr. Koji Fushimi Prof. Yasuchika Hasegawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(58):14438-14443
In this study, we have demonstrated a two-legged, upright molecular design method for monochromatic and bright red luminescent LnIII-silica nanomaterials. A novel EuIII-silica hybrid nanoparticle was developed by using a doubly binding TPPO−Si(OEt)3 (TPPO: triphenyl phosphine oxide) linker. The TPPO−Si(OEt)3 was confirmed by 1H, 31P, 29Si NMR spectroscopy and single-crystal X-ray analysis. Luminescent Eu(hfa)3 and Eu(tfc)3 moieties (hfa: hexafluoroacetylacetonate, tfc: 3-(trifluoromethylhydroxymethylene)camphorate) were fixed onto TPPO−Si(OEt)3-modified silica nanoparticles, producing Eu(hfa)3(TPPO−Si)2-SiO2 and Eu(tfc)3(TPPO−Si)2-SiO2, respectively. Eu(hfa)3(TPPO−Si)2−SiO2 exhibited the higher intrinsic luminescence quantum yield (93 %) and longer emission lifetime (0.98 ms), which is much larger than those of previously reported EuIII-based hybrid materials. Eu(tfc)3(TPPO−Si)2−SiO2 showed an extra-large intrinsic emission quantum yield (54 %), although the emission quantum yield for the precursor Eu(tfc)3(TPPO−Si(OEt)3)2 was found to be 39 %. These results confirmed that the TPPO−Si(OEt)3 linker is a promising candidate for development of EuIII-based luminescent materials. 相似文献
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Photophysical Properties and Efficient,Stable, Electrogenerated Chemiluminescence of Donor–Acceptor Molecules Exhibiting Thermal Spin Upconversion 下载免费PDF全文
Dr. Ryoichi Ishimatsu Dr. Tomohiko Edura Prof. Chihaya Adachi Prof. Koji Nakano Prof. Toshihiko Imato 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(14):4889-4898
The photophysical properties and electrogenerated chemiluminescence (ECL) of three donor–acceptor molecules composed of dicyanobenzene and methyl‐, tert‐butyl‐, and phenyl‐substituted carbazolyl groups, 1,2,3,5‐tetrakis(3,6‐disubstituted‐carbazol‐9‐yl)‐4,6‐dicyanobenzene (4CzIPN‐Me, 4CzIPN‐tBu, and 4CzIPN‐Ph, respectively) are described. These molecules show delayed fluorescence as a result of thermal spin upconversion from the lowest triplet state to the lowest singlet state at room temperature. The three molecules showed yellow to yellowish–red ECL. Remarkably, the ECL efficiencies of 4CzIPN‐tBu in dichloromethane reached almost 40 %. Moreover, stable ECL was emitted from 4CzIPN‐tBu and 4CzIPN‐Ph. In case of 4CzIPN‐Me, the ECL intensity decreased during voltage cycles because of polymerization. Quantum chemical calculations revealed that polymerization was inhibited by the steric hindrance of the bulky tert‐butyl and phenyl groups on the carbazolyl moieties and lowered the spin density on the carbazolyl groups through electron conjugation for 4CzIPN‐Ph. 相似文献
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Shibo Xu Kazutaka Takamatsu Prof. Dr. Koji Hirano Prof. Dr. Masahiro Miura 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(40):9400-9404
A NiCl2(PEt3)2-catalyzed regioselective C−H coupling of 8-aminoquinoline-derived benzamides with oxetanes has been developed. The reaction proceeds with concomitant removal of the 8-aminoquinoline auxiliary to directly form the corresponding seven-membered benzolactones, which frequently occur in natural products and bioactive molecules. Additionally, no stereochemical erosion is observed during the course of the reaction, and the use of enantioenriched and substituted oxetane thus provides a new avenue to the optically active benzolactone. 相似文献
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We report herein an effective method for the construction of 4- and 7-ring benzo-fused thieno[3,2-b]thiophenes, involving palladium-catalyzed intramolecular decarboxylative arylation as the key step. 相似文献
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Yo Hiranoi Miho Hatanaka Koji Nakano 《Journal of polymer science. Part A, Polymer chemistry》2017,55(13):2150-2159
Di‐ and trinuclear cobalt (Co)–salen complexes with a benzene ring as a rigid linker were explored for epoxide polymerizations. The dinuclear Co–salen complex with a 1,2‐phenylene linker showed higher catalytic activity than the dinuclear Co–salen complex with a 1,3‐phenylene linker and the trinuclear Co–salen complex with a 1,3,5‐benzenetriyl linker for the copolymerization of propylene oxide (PO) with carbon dioxide. A combination of the absolute configuration of the two Co–salen moieties was found to affect its catalytic activity. The optimized dinuclear Co–salen complex with a heterochiral combination demonstrated highest activity and maintained its catalytic activity under a low catalyst concentration. The heterochiral dinuclear Co–salen complex also showed high activity for the copolymerization of PO with cyclic anhydride. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2150–2159 相似文献