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排序方式: 共有894条查询结果,搜索用时 31 毫秒
31.
Takeshi Taniguchi Takashi Kawakami Youhei Nishimura Mistutaka Okumura Kizashi Yamaguchi 《Chemical physics letters》2006,420(4-6):397-400
The one-dimensional intermolecular ferromagnetic interaction of a charge-transfer (CT) complex, (BDTA)[Ni(mnt)2] (BDTA: 1,3,2-benzodithiazolyl, mnt: maleonitriledithiolate), is studied by the Kohn–Sham hybrid density functional method, in order to understand the mechanism of the magnetism. All possible effective exchange integrals, J, between the spin pairs of the system indicate that a ferromagnetic interaction (J = 172 cm−1) exists along the b-axis. Magnetic susceptibility, simulated with the ab initio determined J values by the quantum Monte Carlo (QMC) method, is qualitatively consistent with that measured experimentally. 相似文献
32.
The methodology for a copper-catalyzed preparation of diaryl chalcogenide compounds from aryl iodides and diphenyl dichalcogenide molecules is reported. Unsymmetrical diaryl sulfide or diaryl selenide can be synthesized from aryl iodide and PhYYPh (Y = S, Se) with a copper catalyst (CuI or Cu(2)O) and magnesium metal in one pot. This reaction can be carried out under neutral conditions according to an addition of magnesium metal as the reductive reagent. Furthermore, it is efficiently available for two monophenylchalcogenide groups generated from diphenyl dichalcogenide. 相似文献
33.
Chlorination of the N-oxides of furo[2,3-b]- 1a , -[2,3-c]- 1b and -[3,2-c]pyridine 1c with phosphorus oxychloride afforded compounds substituted normally at the α- or λ-position to the ring nitrogen, 2a, 2′a, 2b, 2c, 2′c and 2′c , and in addition, in the case of 1b , compounds substituted on the furan ring, 2′b and 2″b . The structures of these compounds were confirmed from their ir, nmr and mass spectra. The major chlorinated products 2a, 2b and 2c were converted to methoxy- 5a, 5b and 5c , N-pyrrolidyl- 7a, 7b and 7c , and phenylthiofuropyridines 8a, 8b , and 8c . 相似文献
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36.
Dr. Ji-Rong Huang Dr. Muhammad Sohail Dr. Tohru Taniguchi Prof. Dr. Kenji Monde Prof. Dr. Fujie Tanaka 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(21):5947-5951
Spiro[4,5]decanes and polycyclic compounds bearing spiro[4,5]decane systems are important biofunctional molecules. Described are diastereoselective formal (4+1) cycloaddition reactions to afford oxindole-functionalized spiro[4,5]decanes and organocatalytic enantioselective Michael–Henry cascade reactions of the (4+1) cycloaddition products to generate spirooxindole polycyclic derivatives bearing the spiro[4,5]decane system. Spiro[4,5]decanes bearing oxindoles containing three stereogenic centers and spirooxindole polycycles having seven stereogenic centers, including two all-carbon chiral quaternary centers and one tetrasubstituted chiral carbon center, were obtained with high diastereo- and enantioselectivities. 相似文献
37.
Tsugio Kitamura Kunihiko Morizane Masa-Aki Miyaji Shin-Ichi Soda Hiroshi Taniguchi Yuzo Fujiwara 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):465-466
1-Phenylbenzo[b]thiophenium salts are prepared and reacted under thermal and photochemical conditions. The chemical behaviors are discussed. 相似文献
38.
Takeshi Eitoku Kazuya Taniguchi Yuta Nakazato Shunichi Ono Kenji Katayama 《Optical Review》2010,17(1):5-9
Formation process of gold nanoparticles was investigated by near-field heterodyne transient grating method. In the absence
of the protective agents, although the diffusion of H[AuICl2] could be observed after the photo-reduction of H[AuIIICl4], the diffusion of nanoparticle-seeds was not observed. On the other hand, in the presence of the protective agents, the
diffusion of a complex molecule (Au and protective agent) and nanoparticle-seeds could be observed. From these results, it
was found that enough amount of the complex is essential for the nanoparticle formation. We also investigated the formation
process with four different chemicals as a protective agent. The hydrodynamic radius of nanoparticle-seeds generated in the
poly(vinyl pyrrolidone) and TritonX-100 solutions were larger than those generated in the Tween 20 and Brij 58 solutions.
The former two have hydrophilic chain in the molecular structure; on the other hand, the latter two have hydrophobic alkyl
chain. Based on those facts, we concluded that the interaction between the chains of the complex molecule plays an important
role in the nanoparticle formation process. 相似文献
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40.
Direct Synthesis of 1,4‐Diols from Alkenes by Iron‐Catalyzed Aerobic Hydration and C?H Hydroxylation
Takuma Hashimoto Daisuke Hirose Tsuyoshi Taniguchi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(10):2768-2772
Various 1,4‐diols are easily accessible from alkenes through iron‐catalyzed aerobic hydration. The reaction system consists of a user‐friendly iron phthalocyanine complex, sodium borohydride, and molecular oxygen. Furthermore, the effect of additional ligands on the iron complex was examined for a model reaction. The second hydroxy group is installed by direct C(sp3) H oxygenation, which is based on a [1,5] hydrogen shift process of a transient alkoxy radical that is formed by formal hydration of the olefin. 相似文献