著者

田辺 陽 御前 智則 飯田 聖 西井 良典

出版者

The Society of Synthetic Organic Chemistry, Japan

雑誌

有機合成化学協会誌 (ISSN:00379980)

巻号頁・発行日

vol.62, no.12, pp.1249-1259, 2004-12-01 (Released:2009-11-13)

参考文献数

46

被引用文献数

5 7

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Esterification, sulfonylation, amide formation, and silylations are well recognized as frequently used reactions for organic syntheses. Recent syntheses of fine chemicals and complex natural products, however, require further rationalization of these reactions. We describe herein our recent studies in this area including related representative known methods.(i) Recent progresses of catalytic esterifications are surveyed and we introduce two efficient ammonium triflate catalysts (DPAT and PFPAT) for esterification between 1 : 1 mixture of carboxylic acids and alcohols. (ii) Conventional condensation reagents for esterifications, thioesterifications, and amide formation, are listed and we introduce efficient methods using Me2NSO2Cl/ Me2NR and p-TsCl/N-methylimidazole. (iii) As a promising method for the replacement of conventional pyridine-method, we introduce efficient pyridine-free improved methods, which utilize sterically uncrowded tertiary amines such as Me3N·HCl/Et3N and Me2N (CH2) nNMe2 as a key protocol. (iv) We introduce highly powerful, neutral, and catalytic methods for silylations of alcohols (giving enol ethers) and ketones (giving enol silyl ethers) using hydrosilanes, disilanes, and silazanes.

著者

杉山 卓也 中村 武彦 西井 良 菅沼 柾希 宅野 信輔 千葉 裕花 増田 百恵 三井 玲奈

出版者

日本スポーツ産業学会

雑誌

スポーツ産業学研究 (ISSN:13430688)

巻号頁・発行日

vol.30, no.1, pp.1_31-1_40, 2020 (Released:2020-01-24)

参考文献数

12

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The purpose of this research was to investigate the current situation in which youth teams in Europe are producing football players in strong teams and to explore the success model of the youth teams. The youth teams of the European top four major league division teams were examined, and as a result of calculating the contribution points based on the UEFA club ranking, the first place was Real Madrid youth, the second place was Barcelona Youth. Among the top 10 teams in total points, there were teams that showed high points even if they were not such strong teams. Also, although Manchester City Youth has produced many players, it did not differ much from other teams in regard to total points. In addition, there were teams that promoted many players in their top teams, like Athletic Bilbao Youth. Based on the above surveys, it was considered that the teams that successfully trained players could be classified into the following three major categories. ① Multi-player High Level Type, including Real Madrid youth and Barcelona youth, producing many players and operating at a high level. ② Self-Team Contribution Type, including Athletic Bilbao Youth, promoting many players to their own top team. ③ Release to Other Teams Type, including Manchester City Youth, producing numerous players who join other teams

著者

三原 陽子 森川 大 野村 泰志 西井 良典

出版者

日本コンピュータ化学会

雑誌

Journal of Computer Chemistry, Japan (ISSN:13471767)

巻号頁・発行日

vol.16, no.4, pp.102-105, 2017 (Released:2017-10-31)

参考文献数

4

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The (−)-podophyllic aldehydes (Figure 1) exhibit notable antineoplastic cytotoxicity by apoptosis-inducing activities. In this study, we analyzed the selectivity mechanisms of some important reactions in the asymmetric total synthesis of (+)-podophyllic aldehydes which are enantiomers of the (−)-podophyllic aldehydes, by the molecular orbital method. As a result, it was shown that the selectivity of the Grignard reaction in compound 1 (Figure 2) is caused by steric hindrance. Furthermore, it was also indicated that the selectivity of the reduction in compound 2–1 is caused by the localization of LUMO at the reactive site, and the reduction in compounds 2–2 and 2–3 Scheme 2) does not proceed due to the steric hindrance by the trimethoxyphenyl group.

著者

西井 良典

出版者

信州大学

雑誌

若手研究(B)

巻号頁・発行日

2005

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1.ジクロロシクロプロパンの2つのC-Cl結合の連続的高立体選択的変換反応の開発a)ジクロロシクロプロパンの高立体選択的ラジカル的アシル化反応b)1-クロロシクロプロパンカルボン酸エステルのReformatsky型C-C結合形成反応ジブロモシクロプロパンのC-Br結合のC-C結合への変換は数多く報告されているが,C-Brよりも強固なジクロロシクロプロパンの2つのC-CI結合のC-C結合への変換は報告されていない。昨年度,a)ジクロロシクロプロパンの高立体選択的ラジカル的アシル化反応を見出した(Org.Lett.2007,9,563.)。1段階目のC-Cl結合のアシル化反応である。さらなる展開として,この反応の生成物を用いて,2段階目のC-Cl結合の変換反応としてSml_2を用いる高立体選択的なReformatsky型C-C結合形成反応を見出した(投稿準備中)。これらの反応により,初めてジクロロシクロプロパンの2つのC-Cl結合のC-C結合への変換することができるようになった。2.光学活性ジクロロシクロプロパンカルボン酸の不斉アミンを用いる光学分割法および光学活性アルコールとのエステルとしジアステオマ-をカラムで単離し,光学活性ジクロロシクロプロパンカルボン酸に変換する分割法を見出した(Org.Biomol.Chem.2008,6,540-547.)。3.ジクロロシクロプロピルケトンの環拡大反応を用いる非対称多置換チオフエン類の合成と応用:昨年度,見出したシクロプロパン環開裂および脱HClを伴う非対称多置換チオフェン環形成反応を応用し,β-アミロイド捕捉類縁体とされる非対称多置換2,5-ジアリールチオフエン類の合成を達成した。特に3,4位に置換基を有する10種類の2,5-ジアリールチオフェン誘導体を合成した(投稿準備中)。