リベックの自己折り畳み式オクタアミドカビタンに含まれるIr (I) ·CODの分子運動とコンフォーマショナル相互変換
Saša Korom1, Eddy Martin1, Stefano A Serapian1
1Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology , Avgda. Països Catalans 16, 43007 Tarragona, Spain.
Journal of the American Chemical Society
|January 27, 2016
まとめ
イリジウム複合体の制限された回転は,キャビタンド宿主の中で新しいキラル形を作り出します. この超分子複合はキラリティを高め 分子運動に影響を与え ホスト・ゲスト化学の洞察を与えます
科学分野:
- 超分子化学
- 有機金属化学
- 物理有機化学
背景:
- レベックの自己折り畳みオクタアミドカビタンドは ゲスト分子にキラル環境を提供します
- 新しい分子システムを設計するには ホスト-ゲストの相互作用を理解することが重要です
研究 の 目的:
- ヘテロレプティックなL2·Ir(I) ·1,5-サイクロオクタディエン (COD) 複合体のキャビタンド内の軸の回転を調査する.
- オーガノメタリックゲストのヒラリティとダイナミクスに 閉じ込めの影響を調べる
主な方法:
- 陽子核磁気共鳴 (1H NMR) スペクトロスコーピーは,変化する温度で実施されます.
- 実験的観測をサポートする計算分析.
- 熱力学的パラメータを決定する ヴァント・ホフ分析
主要な成果:
- 1H NMRで観測された穴内のIr ((I)) -COD複合体の制限された軸の回転.
- 複合体の対称性 (C2からC4) の温度依存の変化
- 制限された形状の相互変換による低温での新しいキラル形態の出現.
結論:
- キラル・キャビタンド内の閉じ込めは,Ir ((I)) -COD複合体の高いラセミゼーションバリアを誘導する.
- エントロピーを駆動する 熱中性プロセスです
- チラルの宿主-ゲスト複合体は独特のステレオ化学的性質とダイナミクスを表しています.
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