チラルのマクロサイクルナノ炭素のシントンとしての膨張ヘリケーン
Gavin R Kiel1, Katherine L Bay2, Adrian E Samkian1
1Department of Chemistry, University of California, Berkeley, California 94720, United States.
Journal of the American Chemical Society
|May 27, 2020
まとめ
研究者は,アルキン機能化された拡張 [11] ヘリセンのグラムスケール量を合成した. この前駆物質は,安定したキラルナノカーボンへの経路を提供する,フィギュア8ダイマーとアリレンブリッジヘリケーンを含む新しいマクロサイクリック派生物質に変換されました.
科学分野:
- 有機化学
- 材料科学
- ナノテクノロジー
背景:
- 拡張ヘリケンは,キラルナノカーボン構造のための多用途の π-フレームワークです.
- 複雑なヘリケンの産物への効率的な合成経路の開発は極めて重要です.
研究 の 目的:
- アルキン機能化された膨張 [11]ヘリセンのグラムスケール合成を達成する.
- 異なるマクロサイクル誘導体への変換を探求する.
- 新しい化合物の構成安定性とエナチオメリゼーションメカニズムを調査する.
主な方法:
- アルキン機能化された拡張 [11]ヘリセンのグラムスケール合成.
- アルキンの転化により 8 進体形成.
- アリレン・ブリッジヘリエン合成のためのジルコニウム媒介サイクロアディション.
- 密度関数理論の計算により,エナチオメリゼーションのメカニズムが探求される.
主要な成果:
- ヘリケンの前駆体と 8桁のダイマーを グラムスケールで合成した
- 2種類のマクロサイクリック誘導体の形成:フィギュア8ダイマーとアリレンブリッジヘリケーン.
- フェニレンブリッジヘリケンは,前駆体 (<11. 9 kcal/ mol) に比べて,エナチオメリゼーションバリアが著しく高かった (22.1 kcal/ mol).
- 形状8のジメルは,溶液で配置的に不安定であるが,ホモキラル単一結晶を形成し,螺旋状の上部構造によって安定した.
結論:
- アルキーン機能化された拡張ヘリケンは,多様なマクロサイクル構造の貴重な前体である.
- アリレンブリッジドリバティブは,構成的に安定した拡張ヘリケーンにアクセスするための有望な戦略を提供します.
- 図8のダイマーの独特の結晶包装は 奇拉性の超分子安定化を示しています
- 計算上の洞察は,非ラセミックマクロサイクルシステムの将来の設計を導く.
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