ランタニドイオンに対する前例のないサイズ選択性パターンを持つマクロサイクリックリガンド
Aohan Hu1, Samantha N MacMillan1, Justin J Wilson1
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States.
Journal of the American Chemical Society
|July 23, 2020
まとめ
新しいマクロサイクリックリガンドであるマクロディパとマクロトリパは,大と小の両方のランタニドイオンに対する二重選択性を示しています. この画期的な発見は,ランタニドの調整化合物の安定性を調整するための新しい戦略を提供します.
科学分野:
- 協調化学
- 超分子化学
- 材料科学
背景:
- ランタニドイオン (Ln3+) は,通常は調整化合物として,様々な用途において不可欠である.
- 特定のランタニドイオンの選択的結合は,それらの類似した化学特性のために困難である.
研究 の 目的:
- ランタニドイオンに対する二重選択性を持つ新しいマクロサイクリックリガンドの設計と合成.
- これらの新しいリガンドで形成されたランタニド複合体の構造と熱力学的性質を調査する.
主な方法:
- 熱力学的な安定性と選択性を決定するための電位測量定位.
- 構造分析のための核磁気共振 (NMR) スペクトログラフィーとX線結晶学
- 選択性の起源を明らかにするための密度関数理論 (DFT) の計算.
主要な成果:
- マクロディパとマクロトリパという2つの18基のマクロサイクルリガンドが合成された.
- これらのリガンドは前例のない二重選択性を示し,軽量で大きなLn3+と重量で小さなLn3+イオンの両方を結合します.
- 構造研究は,異なるイオンサイズに対応する (10座標型A型から8座標型B型までの) 構成の切り替えを明らかにした.
結論:
- 新しく設計されたリガンドは,ランタニドイオン選択性を効果的に調整できます.
- 観察された二重選択性は,リガンドのストレンスと金属-リガンド結合エネルギーのバランスから生じる.
- この研究は,選択的なランタニド分離と応用技術の開発のための新しいプラットフォームを提供します.
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