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1,4-Phenylene-bridged zinc(II) meso-meso linked diporphyrin arrays were prepared by Ag(I)-promoted coupling reaction in a regioselective manner. 相似文献
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Directly 2,12‐ and 2,8‐Linked ZnII Porphyrin Oligomers: Synthesis,Optical Properties,and Coherence Lengths
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Dr. Hua‐Wei Jiang Taeyeon Kim Dr. Takayuki Tanaka Prof. Dr. Dongho Kim Prof. Dr. Atsuhiro Osuka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(1):83-87
Directly 2,12‐ and 2,8‐linked ZnII porphyrin oligomers were prepared from 2,12‐ and 2,8‐diborylated ZnII porphyrin by a cross platinum‐induced coupling with a 2‐borylated ZnII porphyrin end unit followed by a triphenylphosphine (PPh3)‐mediated reductive elimination. Comparative studies on the steady‐state absorption and fluorescence spectra and the fluorescence lifetimes led to a conclusion that the exciton in the S1 state is delocalized over approximately four and two ZnII porphyrin units for 2,12‐ and 2,8‐linked ZnII porphyrin arrays, respectively. 相似文献
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Flexible transparent fluorinated nanohybrid with innovative heat‐resistance property—new technology proposal for fabrication of transparent materials using “crystalline” polymer
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Muhammad Abdullah Al Mamun Youichi Soutome Qi Meng Atsuhiro Fujimori 《Journal of Polymer Science.Polymer Physics》2015,53(23):1674-1690
A new technology for the production of transparent material, using a “crystalline” polymer, is proposed in this study. In addition, a heat‐resistant transparent flexible plastic film with a high hydrophobic surface and a thermal decomposition temperature near 400 °C was created. Partially fluorinated crystalline polymer with switchboard‐type lamellae results high transparency as a consequence of the formation of a high‐density amorphous structure based on high‐temperature drawing just below the melting point at 250 °C. Melt‐compounding with montmorillonite modified by the long‐chain quaternary phosphonium with high coverage induces formation of a nanohybrid that retains transparency and also results in an increase in the thermal degradation temperature by over 50 °C. Through this technology, which results in heat‐resistance, transparency, and flexibility, the nano‐micro‐millimeter structures of solid‐state polymers are hierarchically controlled, which enables the creation of new materials. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1674–1690 相似文献
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Atsuhiro Nabei Takayoshi Kuroda-Sowa Toshiyuki Shimizu Takashi Okubo Masahiko Maekawa Megumu Munakata 《Polyhedron》2009,28(9-10):1734-1739
The preparation and magnetic properties of three Fe(II)–bis-Schiff base complexes, [Fe2(L1)2(4,4′-bpy)] · MeOH (1), [Fe(L2)(EtOH)] (2) and [Fe(L3)(MeOH)] (3) (L1 = N,N′-bis(2-hydroxy-1-naphthaldehyde)-1,2-phenylenediimine; L2 = N,N′-bis(salicylidene)-1,2-phenylenediamine; L3 = N,N′-bis(5-Cl-salicylidene)-1,2-phenylenediamine; 4,4′-bpy = 4,4′-bipyridine) are reported. X-ray single crystal structure analyses for 1–3 reveal that 1 shows a dinuclear Fe(II)–bis-Schiff base complex bridged by 4,4′-bpy, while 2 and 3 show mononuclear structures. Molecular packing of 2 shows a uniform one-dimensional chain structure through hydrogen bonds and Fe?π interaction and that of 3 indicates significant π–π interaction to form a dimmer structure. The χT–T plots of 1–3 show all ferromagnetic interaction at low temperature. The origin of the ferromagnetic interaction observed in 2 is tentatively ascribed to the dimer formation through Fe?π interaction at low temperature. 相似文献
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Yusuke Matsuo Dr. Takayuki Tanaka Prof. Dr. Atsuhiro Osuka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(36):8144-8152
N,N’-Diarylated tetrabenzotetraaza[8]circulenes 3 a and 3 b were synthesized in good yields by a reaction sequence involving oxidation of tetrabenzodiazadithia[8]circulene 5-Oct and SNAr reaction with aniline derivatives. The obtained aza[8]circulenes 3 a and 3 b were easily oxidized to give their radical cations 3 a+ and 3 b+ , which are highly stable under ambient conditions. X-ray diffraction analysis of radical cation 3 a+ showed a face-to-face dimer arrangement with an interplanar separation of 3.320 Å. The spin density of 3 a+ was calculated to be delocalized over the whole circulene π-systems with spin–spin exchange integral (J=−144 cm−1) in the dimeric part. These radical cations displayed far red-shifted absorption bands reaching to 2000 nm. Thus this study has proved the hetero[8]circulene scaffold to be a new entry of promising electronics and spin materials. 相似文献
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