折りたたまれたオルトフェニレンサブユニットを持つトウィストマクロサイクル
Zacharias J Kinney1, C Scott Hartley1
1Department of Chemistry & Biochemistry, Miami University , Oxford, Ohio 45056, United States.
Journal of the American Chemical Society
|March 18, 2017
まとめ
研究者は芳香質の折り畳み物を ねじれたマクロサイクルに組み立てました これらの形状の持続的な三角形構造は,マクロサイクル内に閉じ込められたとき,より遅い形状のダイナミクスを示します.
科学分野:
- 超分子化学
- 有機化学
- ポリマー科学
背景:
- フォルダマーとは,定義された二次構造を採用し,機能的性質を示すと知られているオリゴーマーである.
- 折りたたみ子ユニットをより大きなアーキテクチャに組み込むことは,バイオマクロモレキュールの高次構造にとって不可欠ですが,未熟のままです.
- オフェニレンなどの芳香性折りたたみ物質は,複雑な構造に自己組み立てを調査するための簡単なプラットフォームを提供します.
研究 の 目的:
- O-フェニレン・フォルダマーのダイナミックな共性組成をねじれたマクロサイクル構造に調査する.
- 形成されたマクロサイクルの形状の持続性,対称性,形状の動態を特徴づける.
- 折りたたみ子ユニットに対するマクロサイクル収束の影響を調査する.
主な方法:
- ダイナミックな共性イミン形成を用いて,様々な棒状のリンク子 (p-フェニレン,トラン,ディフェニルブタディエン) を含むo-フェニレンテトラマーを組み立てました.
- 変化温度 NMR を含む核磁共振 (NMR) 光譜を用いて合成された [3 + 3] マクロサイクルを特徴づけました.
- 構成分布を分析し,ホモキラル (D3対称) とヘテロキラル (C2対称) のコンフォマーを区別した.
主要な成果:
- 効率的なマクロサイクリングが達成され,形状が持続し,内径 ~ 2 nm の回転したコアを持つ三角形のマクロサイクルの形成につながった.
- NMRスペクトロスコーピーはD3とC2対称コンフォマーを成功裏に区別しました.
- マクロサイクル構造内の閉じ込めは,o-フェニレン分子の逆転ダイナミクスを遅らせることが観察されました.
結論:
- ダイナミック・コバルント化学は,複雑な折り畳み基のマクロサイクルを構築するための効果的な経路を提供します.
- 形成されたマクロサイクルは,形状の持続性と調整可能な対称性を有する.
- マクロサイクルの閉じ込めは,折りたたみ子ユニットの構成動力学に影響を与え,より高い秩序の構造制御の洞察を提供します.
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