遠距離安定相互作用の起源と範囲,およびそれに関連したSOMO-HOMO変換によるディストニックラジカルアニオンへの変換

Ganna Gryn'ova¹, Michelle L Coote

¹ARC Centre of Excellence for Free Radical Chemistry and Biotechnology, Research School of Chemistry, Australian National University , Canberra, Australian Capital Territory 0200, Australia.

Journal of the American Chemical Society

|October 5, 2013

まとめ

新しい極性効果は,クーロンビック相互作用を通じて,急性およびアニオンを安定させ,酸性に影響を与え,合成および生物学的プロセスのためのpH交換可能な化合物を可能にします.

科学分野:

物理化学物理化学
量子化学とは,量子化学である.
有機化学オーガニック・ケミストリー

背景:

ディストンの根幹アニオンは,相互に結合していないアニオンと根幹の分子が特徴です.
これらのシステムの長距離相互作用を理解することは,化学設計において極めて重要です.

研究の目的:

SOMO-HOMOの変換されたディストニク・ラジカルアニオンにおける安定作用の範囲と起源を調査する.
ラジカルとアニオンの安定性を影響する新しいタイプの極性効果を特徴づける.

主な方法:

高レベルの量子化学計算が採用されました.
分析は,クーロンビック相互作用と,その根源的な種における持続性に焦点を当てた.

主要な成果:

デプロトネーションは遠隔のラジカルを数十kJ/molで安定させ,遠隔のラジカル形成はpKa単位で遠隔の酸性を増加させる.
標準的な極性効果とは異なる新しい非方向的極性効果が特定されました.
安定化は,非局所化ラジカルと安定性の低いアニオンで最大化され,溶媒に依存しています.

結論:

特定された極性効果は広範囲で,pHを切り替えるような急性放出化合物の設計に使用できる.
この効果は生物学的システムに作用し,激素攻撃と酵素触媒に影響を与える可能性があります.

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