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Title: Enantioselective Synthesis of 1,2-Benzothiazine 1-Imines via Ru-II/Chiral Carboxylic Acid-Catalyzed C-H Alkylation/CyclizationAuthors: Huang, Long-Tao; Kitakawa, Yuta; Yamada, Kodai; Kamiyama, Futa; Kojima, Masahiro; Yoshino, Tatsuhiko; Matsunaga, ShigekiAbstract: Sulfondiimines are diaza-analogues of sulfones with a chiral sulfur center. Compared to sulfones and sulfoximines, their synthesis and transformations have so far been studied to a lesser extent. Here, we report the enantioselective synthesis of 1,2-benzothiazine 1-imines, i.e., cyclic sulfondiimine derivatives from sulfondiimines and sulfoxonium ylides via C-H alkylation/cyclization reactions. The combination of [Ru(p-cymene)Cl-2](2) and a newly developed chiral spiro carboxylic acid is key to achieving high enantioselectivity.

Title: Synthesis of Benzo[c]azepine-1,3(2H)-diones via C−H Alkylation/Cyclization with α,β-Unsaturated Acyl FluoridesAuthors: Hosoi, Satoko; Hirata, Yuki; Kurihara, Takumaru; Kojima, Masahiro; Yoshino, Tatsuhiko; Matsunaga, ShigekiAbstract: Transition-metal-catalyzed directed C-H functionalization reactions are a powerful method to construct N-heterocycles. However, compared to the formation of five- and six-membered rings, that of seven-membered rings has been much less explored. Here, the synthesis of benzo[c]azepine-1,3(2H)-diones is described, which are benzene-fused seven-membered imides, from hydroxamates and α,β-unsaturated acyl fluorides via C-H activation using a Cp*Rh(III) catalyst. Under mild reaction conditions, this reaction affords benzo[c]azepine-1,3(2H)-diones that bear a substituent at the 5-position.

Title: Spawning habitat characteristics and egg mortality in relation to river geomorphology and run-times of chum salmon (Oncorhynchus keta) in a metropolitan river system, northern JapanAuthors: Aruga, Nozomi; Morita, Kentaro; Aruga, Makoto; Ueda, Kazutoshi; Fujii, Kazuya; Orito, Kiyoshi; Watanabe, Keizo; Nakamura, FutoshiAbstract: We investigated the geomorphology and environmental variables in which early- and late-run chum salmon groups spawn in an urban section of the Toyohira River, northern Japan, in relation to egg mortality, where a braided riverbed had been developing before river improvement occurred. Geomorphic units in the river channel having the highest proportions were riffles > the upwelling zone of gravel bars > pools > secondary channels. Most redds (> 60%) in the early-run group were built in the upwelling zone of gravel bars in the primary stream, indicating that salmon chose this geomorphic unit for spawning. A greater proportion of spawning redds in the late-run ...

Title: Solid-State Electrochemical Thermal Transistors (Adv. Funct. Mater. 19/2023)Authors: Yang, Qian; Cho, Hai Jun; Bian, Zhiping; Yoshimura, Mitsuki; Lee, Joonhyuk; Jeen, Hyoungjeen; Lin, Jinghuang; Wei, Jiake; Feng, Bin; Ikuhara, Yuichi; Ohta, Hiromichi

2023年4月の月間アクセスランキングを掲載しました。

タイトル: Nonlinear Model Order Reduction of a Variable Reluctance Stepper Motor Using the Parameterized Cauer Ladder Network Method著者: Tobita, Miwa; Matsuo, Tetsuji抄録: The parameterized Cauer ladder network (CLN) method, which is a recently developed nonlinear model order reduction (MOR) method, was applied to the analysis of a variable reluctance (VR) stepper motor. To represent the magnetic saturation, we parameterized the stator network using the coil magnetic flux and input sequence. The rotor network adopted the CLN to investigate the effect of the eddy current. The CLN method was effective in analyzing the continuous rotation, stepwise rotation, and step-out motion.

タイトル: UVSOR BL-1Uにおけるレーザーコンプトンガンマ線を用いた非破壊同位体識別イメージング技術の基礎研究著者: 大垣, 英明抄録: レーザコンプトン散乱ガンマ線を用いた非破壊同位体識別イメージングを，原子力安全基礎研究として進めている。レーザコンプトン散乱ガンマ線は高エネルギー電子ビームと高出力レーザーの衝突から得られる高機能ガンマ線であり，非破壊同位体識別イメージングのみならず物性を含む他分野での利用が行われてきている。ここではレーザコンプトン散乱ガンマ線の発生原理や，特に MeV 領域のレーザコンプトン散乱ガンマ線に関して非破壊同位体識別イメージングへの応用や将来の発展性について簡単に解説する。; Non-destructive isotope selective CT imaging technique by using Laser Compton Scattering (LCS) Gamma-ray has been de ...

タイトル: Leech lattice and holomorphic VOA (Research on finite groups, algebraic combinatorics, and vertex algebras)著者: 宮本, 雅彦抄録: この講演では格子の利用に興味を持っている方々を対象とし、リーチ格子とその自己同型群が数理物理で現れる頂点代数をも支配するという新しい魅力を紹介します。記述: joint work with Ching Hung Lam

タイトル: Hall-Janko群が作用する14次元可換非結合代数について (有限群論，代数的組合せ論，頂点代数の研究)著者: 松本, 恭平

タイトル: An overview on design theory (Research on finite groups, algebraic combinatorics, and vertex algebras)著者: 坂内, 英一記述: この原稿はRIMS joint research (代表者：三枝崎剛):「Researchon finite groups, algebraic combinatorics, and vertex algebras」での講演のslidesをほぼそのままの形で記録したものです．この原稿は独自の論文として完成しているものではなく，私が考えているいくつかのことをpreliminary manuscriptという形で述べただけのものであることをご了承ください．ここで述べたことは色々の方と色々の形での共同研究に基づいていますので共同研究の皆様に感謝したいと思います．特にほとんど全てはDa Zhao (京都大学ポスドク)との共同研究の内容です．