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951.
Yuki Sato Misaki Nishimura Dr. Shin-ichi Kawaguchi Dr. Akihiro Nomoto Prof. Dr. Akiya Ogawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(27):6797-6806
The facile synthesis of organophosphorus compounds is of great importance for the development of new synthetic methods by using air-stable sources of phosphorus. In this respect, a synthetic method that is based on a reductive rearrangement and is capable of converting air-stable pentavalent phosphorus compounds into reactive trivalent phosphorus compounds is a powerful tool. Tetraphenyldiphosphine disulfide, which is a shelf-stable solid, was the focus of this study, and it was shown to undergo reductive rearrangement to trigger the bisthiophosphinylation of a variety of alkenes, such as terminal, cyclic, internal, and branched alkenes, 1,3-dienes, and terminal alkynes when exposed to light without any catalyst, base, or additive. 相似文献
952.
Atsushi Narumi Yoko Ohashi Daichi Togashi Yuta Saito Yuji Jinbo Yoshinobu Izumi Keigo Matsuda Toyoji Kakuchi Seigou Kawaguchi 《Journal of polymer science. Part A, Polymer chemistry》2012,50(17):3546-3559
Core crosslinked star (CCS)‐polymers with water‐soluble arms composed of poly(N‐hydroxyethylacrylamide) (PHEAA) are described. N‐Hydroxyethylacrylamide was polymerized by the atom transfer radical polymerization consisting of ethyl 2‐chloropropionate, copper(I) chloride (CuCl), and tris[2‐(dimethylamino)ethyl]amine in an ethanol/water mixed solvent at 20 °C. The obtained PHEAA‐arms were subsequently coupled using N,N′‐methylenebisacrylamide as the crosslinking agent and sodium L ‐ascorbic acid (AscNa) as the reaction activator. A total of 17 representative coupling reactions with diverse conditions are discussed together with the characterizations of the products mainly by size exclusion chromatograph equipped with the multiangle laser light scattering detector (SEC‐MALS). Consequently, the coupling reactions provided CCS‐polymers with PHEAA‐arms (CCS‐PHEAAs) having weight averaged‐molecular weights determined by SEC‐MALS (Mw,MALS) ranging from 63.8 kg mol?1 to 832 kg mol?1, which corresponded to the average arm‐number (Narm) ranging from 4.1 to 42, respectively. CCS‐PHEAA with the Mw,MALS of 250 kg mol?1 was isolated and characterized by small angle X‐ray scattering measurements in 0.05 M NaNO3 aq. at 25 °C, which was shown to possess a star‐shaped structure and exist as single molecules with a radius of gyration at the infinite dilution condition (<Rg2>z,01/2) of 74 ± 4 Å. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
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Koyo Matsuda Isao Yanagisawa Yasuo Isomura Toshiyasu Mase Tadao Shibanuma 《合成通讯》2013,43(14):2393-2402
Thioamides were treated with iodomethane, and then o,o′-diaminobiphenyl or bipyridyl to afford 6-substituted-5H-dibenzo- or dipyrido [1,3]diazepines in good yields. 相似文献
958.
A. Yamaji Y. Yokota T. Yanagida N. Kawaguchi Y. Futami Y. Fujimoto A. Yoshikawa 《Journal of Crystal Growth》2012,352(1):106-109
Ce:LiSrAlF6 and Eu:LiSrAlF6 crystals with different dopant concentrations were grown by the micro-pulling-down method. The crystals with high dopant crystal included the secondary phase as clusters with the plate shape in BSE images. The secondary phases were identified CeF3 and EuF2, respectively, by the EDS analysis and powder-XRD measurement. Eu concentration against the Sr sites in the Eu 2% doped LiSAF crystal were most uniform in the range 0.9–1.6 atm% using the EPMA. 相似文献
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Thamrongsin Siripongsakul Andras Kovacs Amit Kohn Mikihiko Oogane Yasuo Ando 《哲学杂志》2016,96(4):310-319
The Co40Fe40B20(CFB)/MgO/CFB/MgO/CFB-based multilayer was prepared by conventional magnetron sputtering and utilised in the fabrication of double magnetic tunnel junctions (DMTJs) for which the middle CFB layers were island-shaped. By analysing the magnetic property of the CFB islands with Langevin’s equation, it was possible to identify their diameters of 7.6, 8.9 and 11.0 nm; accordingly submicron-scaled DMTJs were fabricated to investigate single-spin transport phenomena. The coulomb staircase and the oscillatory tunnel magnetoresistive (TMR) were able to be observed at 6 K, where the TMR ratio was enhanced up to 60%, which is the highest value ever achieved in this structure. 相似文献