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461.
Shohei Hamada Yoshiyuki WadaTakahiro Sasamori Norihiro TokitohTakumi Furura Takeo Kawabata 《Tetrahedron letters》2014
A method for oxidative kinetic resolution of racemic alcohols catalyzed by chiral nitroxyl radical (R,R)-1 has been developed. This method is especially effective for the kinetic resolution of tert-butyl aryl carbinols (s = up to 23). 相似文献
462.
Shin-ichi Hirashima Takaaki Sakai Kosuke Nakashima Nana Watanabe Yuji Koseki Kanako Mukai Yohei Kanada Norihiro Tada Akichika Itoh Tsuyoshi Miura 《Tetrahedron letters》2014
Diaminomethylenemalononitrile organocatalyst 1 efficiently promotes the asymmetric conjugate addition of malonates to α,β-unsaturated ketones to afford the corresponding addition products in high to excellent yields with up to 98% ee. 相似文献
463.
Shin-ichi Hirashima Kosuke Nakashima Yuki Fujino Ryoga Arai Takaaki Sakai Masahiro Kawada Yuji Koseki Miho Murahashi Norihiro Tada Akichika Itoh Tsuyoshi Miura 《Tetrahedron letters》2014
A diaminomethylenemalononitrile organocatalyst with a cinchona motif efficiently promotes the enantioselective conjugate addition of acetylacetone to various nitroalkenes to yield the corresponding addition products in high to excellent yields with up to 89% ee. 相似文献
464.
Synthesis of Nanoporous Carbon–Cobalt‐Oxide Hybrid Electrocatalysts by Thermal Conversion of Metal–Organic Frameworks 下载免费PDF全文
Dr. Watcharop Chaikittisilp Dr. Nagy L. Torad Dr. Cuiling Li Dr. Masataka Imura Dr. Norihiro Suzuki Dr. Shinsuke Ishihara Prof. Dr. Katsuhiko Ariga Prof. Dr. Yusuke Yamauchi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(15):4217-4221
Nanoporous carbon–cobalt‐oxide hybrid materials are prepared by a simple, two‐step, thermal conversion of a cobalt‐based metal–organic framework (zeolitic imidazolate framework‐9, ZIF‐9). ZIF‐9 is carbonized in an inert atmosphere to form nanoporous carbon–metallic‐cobalt materials, followed by the subsequent thermal oxidation in air, yielding nanoporous carbon–cobalt‐oxide hybrids. The resulting hybrid materials are evaluated as electrocatalysts for the oxygen‐reduction reaction (ORR) and the oxygen‐evolution reaction (OER) in a KOH electrolyte solution. The hybrid materials exhibit similar catalytic activity in the ORR to the benchmark, commercial, Pt/carbon black catalyst, and show better catalytic activity for the OER than the Pt‐based catalyst. 相似文献
465.
Controlled Crystallization of Cyano‐Bridged Cu–Pt Coordination Polymers with Two‐Dimensional Morphology 下载免费PDF全文
Mohamed B. Zakaria Dr. Ming Hu Dr. Yoshihiro Tsujimoto Prof. Yoshio Sakka Dr. Norihiro Suzuki Yuichiro Kamachi Dr. Masataka Imura Dr. Shinsuke Ishihara Prof. Katsuhiko Ariga Prof. Yusuke Yamauchi 《化学:亚洲杂志》2014,9(6):1511-1514
Two‐dimensional (2D) coordination polymers (CPs) have a highly accessible surface area that permits guest molecules to effectively access the micropores in the CPs. Here we report a bottom‐up synthesis of 2D cyano‐bridged Cu–Pt CP nanoflakes using trisodium citrate as a chelating agent, which controls the nucleation rate and the crystal growth. The lateral sizes of the CP nanoflakes are controlled by changing the amount of trisodium citrate used. We strongly believe that our method will be useful for the preparation of other types of 2D CP nanoflakes. The 2D CPs have many active sites for catalytic and electrochemical reactions, and furthermore the assembled CPs can be used as membrane filters. 相似文献
466.
467.
Karin Söderberg Norihiro Muroyama Arisa Yoshimura 《Journal of solid state chemistry》2008,181(8):1998-2005
Using short wavelength X-rays from synchrotron radiation (SPring-8), high-resolution powder diffraction patterns were collected. In order to study both the structural relationship and the mechanism of stability in the CaAl2−xZnx system, among the Laves phases (MgCu2 and MgNi2 type) and KHg2-type structures, the charge density distribution of CaAl2−xZnx as a function of x was obtained from the diffraction data by Rietveld analysis combined with the maximum entropy method (MEM). In the MEM charge density maps overlapping electron densities were clearly observed, especially in the Kagomé nets of the Laves phases. In order to clarify the charge redistribution in the system, the deformation charge densities from the densities formed by the constituent free atoms are discussed. In the ternary MgNi2-type phase, partial ordering of Al and Zn atoms is observed, a finding that is supported by ab-initio total energy calculations. 相似文献
468.
Dr. Kento Iwai Dr. Yoshiyuki Mizuhata Dr. Tomoya Nakamura Dr. Masato Goto Prof. Dr. Atsushi Wakamiya Prof. Dr. Yuichi Shimakawa Prof. Dr. Norihiro Tokitoh 《欧洲无机化学杂志》2023,26(31):e202300337
Zwitterionic triarylmethylium dyes 1 and 2 were synthesized by using a synthetic unit of a tetraarylborate. The zwitterionic structure of 1 and 2 exhibits varied molecular assembly and induces charge transfer transition. These properties gave them specific optical features such as solvatochromism and mechanochromism in the solid state, that is, the green solid of 2 changes to yellow or red solid by dissolution & evaporation or grinding, respectively. The three colors were reproduced independently in different crystal forms, which were prepared from different recrystallization conditions. The diffuse reflectance measurement and powder X-ray diffraction demonstrated the correlation between the colors and the solid-state structures. The single crystal X-ray analysis revealed face-to-face dimeric assembly in each crystal. Among the crystal structures, the intermolecular distances and packing patterns were notable differences. Based on these results, it can be suggested that unique color change of zwitterionic triarylmethylium dyes originates from the alternation of intermolecular interactions. 相似文献
469.
470.