偽 [1] カテネン型柱 [2] シアクラウン プラナー・キラル・インバーションはメタル・カチオンによって誘発され,アニオンによって制御される
Eunji Lee1, Huiyeong Ju1, In-Hyeok Park1
1Department of Chemistry and Research Institute of Natural Science , Gyeongsang National University , Jinju 52828 , S. Korea.
Journal of the American Chemical Society
|July 6, 2018
まとめ
研究者は金属イオンとアニオンを使って 単一の分子のヒラル逆転を初めて達成しました この超分子化学の突破は 分子構造と機能を制御する 新しい洞察をもたらします
科学分野:
- 超分子化学
- 有機化学
- 協調化学
背景:
- チラリティは分子構造と機能において極めて重要であり,ナノ構造から生物学に至るまで様々な分野に影響を与えます
- 特に単一分子における分子キラリティの制御と逆転は 重要な科学的な課題です
- ピラー[n]アレンとその誘導体は,調節可能な性質を持つ多用途のマクロサイクルホストである.
研究 の 目的:
- 金属イオンとアニオンの制御による キラル・インバーションを 単一の分子で実証する
- 協調モードの指示とキラル逆転に影響を与えるアニオンの役割を調査する.
- 柱[5]チアクラウン誘導体の超分子協調化学を調査する.
主な方法:
- パイラー[5]ティアクラウン (rac-L) の合成,偽[1]カタネン型分子.
- 円形二重化とX線結晶学を用いた平面-キラルエナティオマー (in-pS-Lとin-pR-L) の分離と特徴付け.
- 様々なアニオン (ClO4−,NO3−,I−) の存在でHg2+によって誘発されるキラル逆転を調査する.
- アニオン交換と金属イオン除去を含む可逆性研究
- 結晶学的分析で,アニオンの内外調整モードの指示の役割を明らかにする.
主要な成果:
- in-pS-Lからout-pR-Lへの平面キラル逆転は,特にClO4-またはNO3-のような弱調整アニオンの存在でHg2+によって成功裏に誘導された.
- I-のような強い調整アニオンは,Hg2+のエクソコーディネーションを誘導することによって,キラル逆転を防止した.
- 観察されたキラル・インバーションは,チアクラウン腔内の金属イオンのアニオン指向の調整モード (エンド対エクソコーディネーション) に起因するステリック要因に起因する.
- このシステムは,アニオン交換または金属イオン除去時に可逆性を示した.
結論:
- この研究は,金属イオンとアニオンの相乗効果によるキラル逆転の最初の例を示しています.
- アニオンは協調幾何学の決定的なディレクターとして作用し,キラル逆転に必要な形状の変化を決定します.
- この発見は,超分子協調化学に関する新しい視点を提供し,分子キラリティを制御するための新しい戦略を提供します.
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