極性溶媒におけるチェラート協力性の強化
Stefan Henkel1, Maria Cristina Misuraca1, Yudi Ding1
1Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, U.K.
Journal of the American Chemical Society
|May 4, 2017
まとめ
フェノールのような極性溶媒は,亜鉛ポルフィリン複合体の分子内H結合と競合する. しかし,フェノール濃度の増加は,これらの多価系における結合親近性の損失を軽減し,有効なモラリティ (EM) を高めます.
科学分野:
- 超分子化学
- 物理有機化学
- スペクトロスコーピー
背景:
- 分子内水素結合は分子認識と安定性において重要な役割を果たします.
- 極性溶媒は分子内相互作用と競合し,結合親和に影響を与える.
- 溶媒の効果を理解することは 予測可能な結合特性を持つ分子を設計する鍵です
研究 の 目的:
- 亜鉛・ポルフィリン・ピリジン複合体における分子内水素結合形成に対する極性溶媒 (フェノール) の競合効果を調査する.
- 溶媒の組成が分子内H結合形成の有効モラリティ (EM) に与える影響を定量化する.
- 溶媒と溶液の相互作用と協力的結合効果の相互作用を解明する.
主な方法:
- 複合体の形成をモニターするために,高通量UV-visタイトレーションが使用されました.
- 化学的二重変異サイクル (DMC) を有効なモラリティ (EM) を決定するために使用した.
- 24 種類の亜鉛・ポルフィリン・ピリジン複合体を,様々なトルーエン・フェノール溶媒の混合物で研究した.
主要な成果:
- 分子内フェノルアミドH結合の有効モラリティー (EM) は,フェノル濃度が上昇するにつれて (大きさの順序で) 顕著に増加した.
- フェノールはアミド群を強く溶解し,ステリックの質量を増加させ,複合体を不安定化させる.
- 分子内H結合の形成はステリック障害を軽減し,協力的な相互作用の推進力を高める.
結論:
- 極性溶媒による競争的溶解は,多価系における効果的モラリティの増加によって相殺できる.
- この研究は,溶媒の競争が,分子内H結合形成の強化によって弱まるメカニズムを示しています.
- この研究は,競合する溶剤の存在下で調節可能な結合親和性を持つリガンドと複合体の設計に関する洞察を提供します.
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