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991.
992.
Nakamura A Munakata K Kochi T Nozaki K 《Journal of the American Chemical Society》2008,130(26):8128-8129
An alternating copolymer of methyl acrylate with carbon monoxide has been synthesized for the first time via coordination polymerization using palladium complexes of phosphine-sulfonic acid as catalysts. The highly controlled head-to-tail structure of the copolymer was confirmed by NMR spectra. Subsequent insertion of carbon monoxide and methyl acrylate to methylpalladium species provided gamma-ketoalkylpalladium 2. The present system apparently conquered the difficulty in coordination-insertion of CO to 2. 相似文献
993.
Synthetic utility of arylaldehyde N,N-dialkylhydrazones as a practical acyl anion equivalent could be exploited for the first time in the asymmetric imino aza-enamine reaction catalyzed by axially chiral carboxylic acid. 相似文献
994.
Xavier Lepr Eduardo Terrs Yadira Vega-Cantú Fernando J. Rodríguez-Macías Hiroyuki Muramatsu Yoon Ahm Kim Takuya Hayahsi Morinobu Endo Miguel Torres R. Mauricio Terrones 《Chemical physics letters》2008,463(1-3):124-129
We report an efficient method for anchoring Pt clusters (e.g., 6 nm in size) on the surfaces of N-doped multi-walled carbon nanotubes (MWNTs-CNx) using a relatively simple method consisting of a hydrothermal treatment of Na2[PtCl6] · 6H2O and N-doped nanotubes dispersed in acetic acid. The catalytic properties of this material were evaluated finding that the conversion of cinnamaldehyde using Pt-coated MWNTs-CNx could increase up to 6 times with respect to that obtained for uncoated MWNTs-CNx and pure carbon CNTs. Therefore, we envisage this material could be either used as an efficient catalyst or as a sensor. 相似文献
995.
Fuminori Hiramatsu Tetsuya Murayama Takuya Koseki Katsuhide Okada Yoshihito Shiono 《Helvetica chimica acta》2008,91(8):1595-1603
New cadinane sequiterpenoids, strobilols E–K ( 5 – 11 , resp.) have been isolated from a liquid culture of Strobilurus ohshimae. Their structures have been established on the basis of spectral analyses. 相似文献
996.
The new salen-type N(2)S(2) tetradentate ligands, H(2)L(1) and H(2)L(2), which have a donor set comprising oxime and thiol groups, were synthesized. These ligands are obtained as isolable colorless crystals, whereas the imine analogues are too unstable to be isolated. The unsymmetrical N(2)SO ligands, H(2)L(3) and H(2)L(4), were also obtained as stable compounds. When ligands H(2)L(1)-H(2)L(4) are heated above the melting points, they mainly decompose via cleavage of the N-O bonds of a thiosalicylaldoxime moiety to give 1,2-benzisothiazole derivatives. The complexation of the N(2)S(2) ligands (H(2)L(1) and H(2)L(2)) with nickel(II) acetate afforded square-planar mononuclear complexes [Ni(L(1))] and [Ni(L(2))], respectively. In contrast, the complexation of the N(2)SO ligand H(2)L(3) with nickel(II) acetate resulted in cleavage of the N-O bond, giving a tetranuclear complex having a cubane-type Ni(4)O(4) core. The N-O bonds of H(2)L(1)-H(2)L(4) are more readily cleaved when the ligands are allowed to react with copper(II) acetate. In these cases, the alkoxo-bridged dinuclear complexes having a Cu-O-Cu-O four-membered ring are obtained. On the other hand, mononuclear complexes can be obtained by complexation of the ligands (H(2)L(1) or H(2)L(3)) with palladium(II) acetate without N-O bond cleavage. 相似文献
997.
We herein report a new synthetic method for the preparation of α-hydroxyketones by the dioxygenation of alkynes. The reaction proceeds at room temperature under the action of Fe porphyrin and pinacolborane under air as a green oxidant to produce α-hydroxyketones. The mild reaction conditions allow chemoselective oxidation with functional group tolerance. Terminal alkynes in addition to internal alkynes are applicable, affording unsymmetrical α-hydroxyketones that are difficult to obtain by any reported dioxygenation of unsaturated C−C bonds. 相似文献
998.
Cu nanoparticles (CuNPs) were successfully synthesized in situ on ZnO whiskers as a selective scaffold, which were supported in a microstructured paper matrix composed of inorganic fibers; as-prepared paper composites were easy to handle in practical use and demonstrated excellent catalytic performance in the methanol reforming process for effective hydrogen production. 相似文献
999.
1000.
Akiyama M Ikeda A Shintani T Doi Y Kikuchi J Ogawa T Yogo K Takeya T Yamamoto N 《Organic & biomolecular chemistry》2008,6(6):1015-1019
Unmodified [60]fullerenes (C60) were solubilised with high stability using various type of poly(ethylene glycol) (PEG) based block copolymer micelles. Block copolymer micelle-incorporated C60 fullerenes were studied in cultures for biological activities using human cervical cancer HeLa cells. As a result, the cationic block copolymer micelles delivered C60 into the cells depending on their surface densities and showed cytotoxicity under photoirradiation. 相似文献