S-π と O-π 相互作用のバランスを崩す
Jungwun Hwang1, Ping Li1, Mark D Smith1
1Department of Chemistry and Biochemistry , University of South Carolina , Columbia , South Carolina 29208 , United States.
Journal of the American Chemical Society
|September 26, 2018
まとめ
18対を比較した研究によると,硫黄-π (S-π) 相互作用は酸素-π (O-π) 相互作用よりも安定している. この安定性の変化は 原子の違いによって引き起こされ 計算分析によって確認されます
科学分野:
- 物理化学
- コンピュータ化学
- 有機化学
背景:
- 非共性相互作用は分子認識と自己組織化において極めて重要です.
- 硫黄-π (S-π) と酸素-π (O-π) の相互作用の微妙な違いを理解することは,新しい材料と薬の設計の鍵です.
研究 の 目的:
- S-π と O-π 相互作用の相対的な強さを実験的かつ計算的に比較する.
- S-π と O-π 相互作用の安定性スイッチを制御する要因を解明する.
主な方法:
- 36個の分子バランスを使って 総合的な実験調査を行いました
- 18組のS-πとO-πの相互作用を様々な構造,幾何学,溶媒のパラメータで比較した.
- 実験結果を検証するために,二分子複合体 (PhSCH3-アレンとPhOCH3-アレン) の計算研究を行いました.
主要な成果:
- 硫黄と酸素のバランスの折りたたみエネルギーの間の強い線形相関が観察されました.
- O-π 相互作用から S-π 相互作用への安定性の体系的な切り替えが示された.
- コンピュータによる研究は実験的傾向を成功裏に再現した.
結論:
- S-π相互作用の安定性は,O-π相互作用よりも一般的に大きい.
- 観察された好みのシフトは,安定化 (分散,solvophobic) と不安定化 (交換-反発) 条件の相互作用に起因する.
- 酸素と硫黄の間の原子サイズと分極性の違いが 重要な要因です
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