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31.
Ochiai M Tada N Murai K Goto S Shiro M 《Journal of the American Chemical Society》2006,128(30):9608-9609
Stable aliphatic bromonium ylides (RfSO2)2C--Br+C6H4-p-CF3 (Rf = CF3, CF3(CF2)3) have been synthesized and structurally characterized for the first time. X-ray crystallographic analyses indicated a ylide structure with an sp2 hybridization of the ylide carbanions and with little double-bond character for the ylidic bond. The bromonium ylides selectively undergo transfer of the aryl group to nitrogen heterocycles, such as pyridines, yielding N-arylpyridinium salts. This is in a marked contrast to the reaction of the iodonium ylides, which produces pyridinium ylides through transylidations. 相似文献
32.
[reaction: see text] Aminomethano[60]fullerene was synthesized for the first time as a trifluoromethanesulfonic acid salt by applying the Curtius rearrangement of azidocarbonylmethano[60]fullerene as the key reaction. Aminomethano[60]fullerene thus obtained was found to be able to react with various acyl chlorides to afford the corresponding amides. 相似文献
33.
Dr. Tomoki Ogoshi Ryuta Sueto Kumiko Yoshikoshi Dr. Yoko Sakata Prof. Shigehisa Akine Prof. Tada‐aki Yamagishi 《Angewandte Chemie (International ed. in English)》2015,54(34):9849-9852
Activated perethylated pillar[5]arene crystals show an unexpected alkane‐shape‐ and ‐length‐selective gate‐opening behavior. Activated crystals were obtained upon removing solvents from perethylated pillar[5]arene crystals by heating. The activated crystals could quantitatively take up n‐alkanes with carbon chains containing more than five carbon atoms as a consequence of their gate‐opening pressure. As the chain length of the n‐alkanes increased, the gate pressure decreased. A transformation into a herringbone structure was induced when n‐hexane was used as a guest. By contrast, cyclic and branched alkanes were not taken up and could not induce a crystal transformation because they were too large to fit in the cavities of the pillar[5]arene. Alkane‐shape‐selective molecular recognition of pillar[5]arenes in the solution state was translated into the vapor/crystal state. 相似文献
34.
Jin Q Ikeda T Fujishima M Tada H 《Chemical communications (Cambridge, England)》2011,47(31):8814-8816
The electronic modification of TiO(2) with highly dispersed NiO particles smaller than ca. 2 nm by the chemisorption-calcination-cycle technique has given rise to a high level of visible-light-activity exceeding that of iron oxide-surface modified TiO(2) simultaneously with the UV-light-activity being significantly increased. 相似文献
35.
A Soluble Dynamic Complex Strategy for the Solution‐Processed Fabrication of Organic Thin‐Film Transistors of a Boron‐Containing Polycyclic Aromatic Hydrocarbon 下载免费PDF全文
Kyohei Matsuo Dr. Shohei Saito Prof. Dr. Shigehiro Yamaguchi 《Angewandte Chemie (International ed. in English)》2016,55(39):11984-11988
The solution‐processed fabrication of thin films of organic semiconductors enables the production of cost‐effective, large‐area organic electronic devices under mild conditions. The formation/dissociation of a dynamic B?N coordination bond can be used for the solution‐processed fabrication of semiconducting films of polycyclic aromatic hydrocarbon (PAH) materials. The poor solubility of a boron‐containing PAH in chloroform, toluene, and chlorobenzene was significantly improved by addition of minor amounts (1 wt % of solvent) of pyridine derivatives, as their coordination to the boron atom suppresses the inherent propensity of the PAHs to form π‐stacks. Spin‐coating solutions of the thus formed Lewis acid–base complexes resulted in the formation of amorphous thin films, which could be converted into polycrystalline films of the boron‐containing PAH upon thermal annealing. Organic thin‐film transistors prepared by this solution process displayed typical p‐type characteristics. 相似文献
36.
Imaging of Oxygen Diffusion in Individual Platinum/Ce2Zr2Ox Catalyst Particles During Oxygen Storage and Release 下载免费PDF全文
Dr. Hirosuke Matsui Dr. Nozomu Ishiguro Kaori Enomoto Dr. Oki Sekizawa Prof. Dr. Tomoya Uruga Prof. Dr. Mizuki Tada 《Angewandte Chemie (International ed. in English)》2016,55(39):12022-12025
The spatial distribution of Ce3+ and Ce4+ in each particle of Ce2Zr2Ox in a three‐way conversion catalyst system was successfully imaged during an oxygen storage/release cycle by scanning X‐ray absorption fine structure (XAFS) using hard X‐ray nanobeams. For the first time, nano‐XAFS imaging visualized and identified the modes of non‐uniform oxygen diffusion from the interface of Pt catalyst and Ce2Zr2Ox support and the active parts in individual catalyst particles. 相似文献
37.
38.
An Efficient Method for the Conjugation of Hydrophilic and Hydrophobic Components by Solid‐Phase‐Assisted Disulfide Ligation 下载免费PDF全文
Kyohei Muguruma Takuya Shirasaka Daichi Akiyama Dr. Kentarou Fukumoto Dr. Akihiro Taguchi Dr. Kentaro Takayama Dr. Atsuhiko Taniguchi Prof. Yoshio Hayashi 《Angewandte Chemie (International ed. in English)》2018,57(8):2170-2173
Chemical conjugation between hydrophilic and hydrophobic components is difficult because of their extremely different solubility. Herein, we report a new versatile method with a solid‐phase‐assisted disulfide ligation to overcome the difficulty of conjugation attributed to solubility. The method involves two steps in a one‐pot process: 1) loading of a hydrophobic molecule onto a resin in an organic solvent, and 2) release of the solid‐supported hydrophobic molecule as a conjugate with a hydrophilic molecule into an aqueous solvent. This strategy allows the use of a suitable solvent system for the substrates in each step. Conjugates of a water‐insoluble drug, plinabulin, with hydrophilic carriers that could not be prepared by solution‐phase reactions were obtained in moderate yields (29–45 %). This strategy is widely applicable to the conjugation of compounds with solubility problems. 相似文献
39.
40.
Matsumoto T Kominami T Ueda K Sugimoto T Tada T Noguchi S Yoshino H Murata K Shiro M Negishi E Toyota N Endo S Takahashi K 《Inorganic chemistry》2002,41(18):4763-4769
The 2:1 charge-transfer (CT) salts (1(2).FeBr(4) and 1(2).GaBr(4)) of ethylenedithiotetrathiafulvalenoquinone-1,3-dithiolemethide (1) with FeBr(4)(-) and GaBr(4)(-) counteranions were obtained as needle crystals, whose structures are almost the same as each other. The 1 molecules form a one dimensionally stacked column with alternation of their molecular axis direction, while the counteranions are aligned in parallel with the 1-stacked columns with the direction of their distorted-tetrahedral geometry maintained. The room-temperature electrical conductivities measured on the single crystals of 1(2).FeBr(4) and 1(2).GaBr(4) were 4.6 and 2.1 S cm(-1), respectively. From the temperature dependences of their electrical conductivities in both cases the electrical conducting properties were metallic between ca. 170 and 300 K, but below ca. 170 K converted to be semiconducting and continued till 5 K, although the activation energies are very small (4-10 meV). For 1(2).FeBr(4) very weak and antiferromagnetic interaction occurred between the d spins of FeBr(4)(-) ions in the temperature range of ca. 1-300 K. However, below ca. 15 K the ferromagnetic interaction was reversely preferential possibly by participation of the pi spin of 1. 相似文献