柱の適応平面性[5]アレンはn-アルケンの長さに逆転する
Keisuke Adachi1, Shixin Fa1,2, Keisuke Wada1
1Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
Journal of the American Chemical Society
|March 28, 2023
まとめ
この研究は,含まれているn-アルカンの長さに基づいて,そのキラリティを適応できる新しい柱[5]アレンホストを導入した. この分子システムは長さに依存したキラル逆転を示し ホスト・ゲスト化学の新たな可能性を提示しています
科学分野:
- 超分子化学
- ホスト・ゲスト・ケミストリー
- チラルの認識
背景:
- ホスト分子のキラリティはゲスト分子の影響を受けます.
- 宿主キラリティを中性,アキラ n-アルカンに適応することは,弱い相互作用のために困難です.
研究 の 目的:
- n-アルケンの長さに応じてキラリティに適応するホストシステムを開発する.
- マクロサイクル宿主における長さに依存するキラル逆転のメカニズムを調査する.
主な方法:
- ステレオジェニックな炭素とブロミン原子を基にしたピラー[5]アレンベースのマクロサイクリックホストを使用した.
- 異なる長さのn-アルカン (n-ペンタン,n-ヘクサン,n-ヘプタン) をゲストとして使用しています.
- 結晶構造分析と理論的な計算で裏付けられた結果
主要な成果:
- ピラール[5]アレンの宿主体は長さに依存したキラル逆転を示し,短いn-アルケンのpS型と長いn-アルケンのpR型に好意を示した.
- 温度がキラル偏好に影響し,n-ヘクサンはより高い温度でpR,より低い温度でpSを好む.
- 結晶構造と理論的な計算により,同位体の安定性の違いが確認されました.
結論:
- n-アルケンの長さに適応するキラリティを持つユニークな宿主システムを示した.
- ゲストの特性に基づく選択的分子認識におけるマクロサイクルホストの可能性を強調した.
- ホスト・ゲスト・コンプレックスにおける適応性キラリティの制御における重要な要因として,温度を示した.
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