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Jintoku H Sagawa T Takafuji M Ihara H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(41):11628-11636
A new approach for fabricating donor-acceptor assembled systems is demonstrated, based on J-type ordered aggregation of a low-molecular zinc porphyrin derivative and subsequent integration of a pyridylated fullerene derivative with coordination and orientation onto the porphyrin aggregates. This system achieves unusually high efficiencies in fluorescence quenching during one-to-one mixing of the donor and acceptor. Moreover, the Stern-Volmer constant (K(SV)) and association constant (K) of this system are 2520 and 56 times higher, respectively, than those of the corresponding nonassembled system. The quenching efficiency is thermotropically switchable, since ordered-to-disordered transitions are essential characteristics of noncovalent low molecular assemblies. 相似文献
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Three thiophene-containing compounds were newly synthesized as low molecular weight blocks to construct non-covalent and highly ordered π-conjugation systems. Typical emission enhancement and quenching based on the J- and H-type orientations, respectively, of the thiophene moiety were realized and controlled by lipid membrane-like phase transition and separation behaviours. 相似文献
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We report here the one-pot synthesis of 1,2,3-triazoles of arylboronic acids in water. An efficient method has been developed for the synthesis of 1,2,3-triazoles via a one-pot reaction of an arylboronic acid with sodium azide in the presence of Cu(2)-β-CD (CD = Cyclodextrin) as a nanocatalyst in water followed by a click cyclization reaction with an alkyne at room temperature in air without any additives. This method is simple, rapid, and high yielding. 相似文献
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Acetoxyisothiocyanates were prepared by a one-pot synthesis from aminoalcohol, carbon disulfide and acetic anhydride. 相似文献
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A series of new buta-1,3-diene derivatives possessing a (diethoxyphosphinoyl)difluoromethylene unit at the terminal carbon was prepared to examine the reactivity for Diels-Alder cycloaddition with various representative dienophiles. 相似文献
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Tsutomu Yokomatsu Nobuko Nakabayashi Keita Matsumoto Shiroshi Shibuya 《Tetrahedron: Asymmetry》1995,6(12):3055-3062
A kinetic resolution of cis-1-diethylphosphonomethyl-2-hydroxymethylcyclohexane1 by lipase has been developed. The transesterification of (±)−1 with vinyl acetate in the presence of Lipase AK without solvent proceeded to give (+)−1 and the corresponding acetate (+)−5 in good yield and high enantiomeric ratio. The alcohol (+)−1 was transformed to the optically active hydantoins 12 and 13, possible intermediates for the synthesis of conformational constrained analogues of AP-5. 相似文献