ハロゲン結合によって組み立てられた結晶型超分子ロータのダイナミック特性
Luca Catalano1,2, Salvador Pérez-Estrada2, Giancarlo Terraneo1
1Laboratory of Nanostructured Fluorinated Materials (NFMLab), Department of Chemistry, Materials, and Chemical Engineering "Giulio Natta", Politecnico di Milano , via L. Mancinelli 7, 20131 Milano, Italy.
Journal of the American Chemical Society
|November 20, 2015
まとめ
研究者は 結晶分子ローターを作るための モジュール式キットを開発しました これらのロータは超高速回転で 調節性のある材料を設計するための新しい方法を示しています
科学分野:
- 超分子化学
- 材料科学
- 有機化学
背景:
- 分子ローターは 調節可能な動的特性を持つ先進的な材料の開発に不可欠です
- 多様な分子ローター構造の設計と合成は 挑戦的かもしれません
- 自己組み立ては複雑な分子構造を 構築するための有望な経路を提供します
研究 の 目的:
- 結晶分子ロータを準備するためのモジュラー分子キットを設計する.
- ダイナミックな性能と物理的な性質の多様な構造に簡単にアクセスできます.
- 新しい自己組み立て分子ロータの回転力学とメカニズムを調査する.
主な方法:
- ローターとしてダイアザビシクロ[2.2.2]オクタンとステータとして5つのフッ素置換ヨドベンゼンを使用したモジュラーアプローチを使用した.
- 結晶分子ロータの自己組み立てのためにハロゲン結合を使用しています.
- ローテーションダイナミクスを研究するために,変数温度 (1) H T1 のスピン・グリッド・リラクゼーション測定を行った.
- 四極エコー (2) H NMR測定の線形分析を行い,回転軌道を決定した.
主要な成果:
- モジュラーキットとハロゲン結合を用いて 結晶分子ロータを 合成しました
- 合成された全ての構造に対して超高速なブラウン回転を証明した.
- 2.4-4.9 kcal/molの活性化エネルギーと (1-9) × 10(12) s(-1のプレエクスポネンショナル因数で決定した.
- NMRデータは3倍または6倍の対称電位と一致する回転軌道を示した.
結論:
- モジュール式キットは,様々な結晶分子ローターのライブラリに簡単にアクセスできます.
- 自己組み立てのロータは効率的で超高速な回転ダイナミクスを示しています.
- この研究は 精密に制御された運動を持つ 分子機械や材料の設計の基礎を 置いています
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