パラジウム触媒によるC(60) の地域選択的非対称テトラアリレーション
Masakazu Nambo1, Atsushi Wakamiya, Shigehiro Yamaguchi
1Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan.
Journal of the American Chemical Society
|November 19, 2009
まとめ
新しいパラジウム触媒反応により,C(60) フルレンの選択的テトラアリレーションが可能になり,高地域選択性を持つテトラアリレーションされたフルレンが得られます. この方法は,フルレン機能化に対する正確な制御を提供します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- マテリアルサイエンス 材料科学
- カタリシス カタリシス カタリシス
背景:
- C60などのフルレンは,独特の電子的および構造的特性を有する炭素アロトロップである.
- フラーレンの機能化は,様々な用途に合わせてそれらの性質を調整するために不可欠です.
- パラジウム触媒反応は有機合成の多用途なツールであり,複雑な分子構造を可能にします.
研究 の 目的:
- C(60) フルレンのパラジウム触媒テトラアリレーション法を確立する.
- フラーレンケージの選択的および地域選択的機能化を達成するために.
- 観察された選択性の根底にあるメカニズムを調査する.
主な方法:
- C(60) を,パラジウム触媒 (PdCl2[P(OPh) 3) 2) の存在下で,アルリル塩化物およびアルリルトリビュチルチンで処理する.
- 反応は,1,2-ジクロルベンゼンで50°Cで実施した.
- 反応中間物質と地域選択性の分析を含むメカニズム研究.
主要な成果:
- この反応により,テトラアリル化フルレンは得られ,74%の高収量で成功しました.
- テトラアリレーションは,実質的に完全な地域選択性を示し,加算パターンの正確な制御を示した.
- 機械学的調査は,bis ((pi-allyl) palladium intermediate経由で連続した核愛性/電愛性アリレーションを含む経路を示唆した.
結論:
- C ((60) の新しいPd触媒テトラアリレーションが開発され,機能化されたフルレレンへの選択的経路を提供している.
- 高い地域選択性は,アリレーションステップに影響を与えるステリックおよび電子的要因の組み合わせに起因する.
- この方法論は,複合フルレン誘導体の制御合成のための貴重なアプローチを提供します.
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