ゲオメトリク・コンプリメンタリティ・イン・アセンブリ・アンド・ゲスト・リカग्निション・オブ・ベント・ヘテロレプティック・シス-[Pd2LA2 LB2] コオディネーション・ケージ
Witold M Bloch1, Yoko Abe1, Julian J Holstein1
1Faculty of Chemistry and Chemical Biology, TU Dortmund University , Otto-Hahn-Straße 6, 44227 Dortmund, Germany.
Journal of the American Chemical Society
|September 23, 2016
まとめ
研究者は2つの異なるリガンドを使用して,新しいヘテロレプティックなパラジウム調整ケージを合理的に組み立てました. この制御された自己組み立て戦略により,超分子構造の複雑性と機能性が向上します.
科学分野:
- 超分子化学
- 協調化学
- 材料科学
背景:
- 多コンポーネントアセンブリを独占的に形成することは,エントロピー要因のために困難です.
- パラジウム (II) カチオンと角形リガンドは,明確に定義されたホモレプス調整ケージを形成することができる.
- 既存の方法は 複雑な混合リガンド構造の制御された組み立てに 苦労しています
研究 の 目的:
- [Pd2LA2LB2]4+調整ケージを合理的に設計し組み立てること.
- 複合的,混合リガンドの超分子構造を作るための制御された方法を実証する.
- 形状認識などの応用のための 組み立てられたケージの可能性を 探求するためです
主な方法:
- LAとLBの2つの角型リガンドの合理的な設計,幾何学的な補完性.
- 設計されたリガンドでパラジウム (II) カチオンの自己組み立て.
- X線解析,ESI-MS,COSY,DOSY,NOESYを用いた特徴づけ
- DFT計算を用いた計算分析
主要な成果:
- 曲線構造の cis-[Pd2LA2LB2]4+ ヘテロレプティックケージの合理的な組み立てに成功した.
- [Pd2LA4]4+と[Pd4LB8]8+) を中間または副産物として形成する.
- ヘテロレプティックケージをケージ対ケージ変換で熱力学的最小値として確認する.
- NOESYとDFTによるヘテロレプティックケージ内のリガンドのシス構成の実証.
結論:
- リガンドと金属ノードの幾何学的な互補性は,制御されたヘテロレプティックケージ形成を可能にします.
- この戦略は 複雑性を高め 自己組み立てケージに複数の機能を導入する 強力な経路を提供します
- 頑丈なヘテロレプティックケージは,形状選択のゲスト結合などの分子認識の応用の可能性を示しています.
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