グループ11 メタルアミド触媒によるアソメチンイミンの非対称サイクロアディション反応と末端アルキネの反応
Takaki Imaizumi1, Yasuhiro Yamashita, Shū Kobayashi
1Department of Chemistry, School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|December 1, 2012
まとめ
私たちは,グループ11の金属アミドを用いて,N,N-バイサイクル型ピラゾリジノン誘導体を合成するための新しい触媒的方法を開発しました. この反応は高収量,地域選択性,および非対称合成におけるエナチオ選択性を提供します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- ヘテロサイクル化学 ヘテロサイクル化学
背景:
- 1,3-二極性サイクロアディション反応は,ヘテロサイクリック化合物の構築に不可欠です.
- これらの反応のための効率的な触媒システムの開発は,依然として研究分野です.
- アゾメチンイミンとターミナルアルキンは,有機合成における汎用的な構成要素である.
研究 の 目的:
- アゾメチンイミンの末端アルキンと1,3-二極サイクロアディションのための新しい触媒システムを開発する.
- 独特の置換パターンを有するN,N-バイサイクルピラゾリジノン誘導体を合成する.
- これらのヘテロサイクルの高エナチオセレクティブ性の非対称合成を達成するために.
主な方法:
- サイクル添加反応の触媒として,グループ11の金属アミドを使用した.
- 反応基質としてアゾメチンイミンとターミナルアルキンを使用した.
- 反応経路と選択性の決定因子を理解するために,機械学的研究を行った.
主要な成果:
- 1,3-二極サイクロアディションによるN,N-バイサイクルピラゾリジノン誘導体を成功して合成しました.
- サイクルロードダクトでユニークな5.7不置換パターンを達成しました.
- 高い収穫量,独特の地域選択性,および非対称な変種における高いエナチオ選択性があることが実証されています.
結論:
- グループ11の金属アミド触媒は,N,N-バイサイクルピラゾリジノンの効率的な経路を提供します.
- 開発された方法は非対称合成に適用され,エナティオメリックに濃縮されたヘテロサイクルが得られます.
- 機械的洞察は,この変革における地域選択性を支配する重要な要因を明らかにします.
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