イオンペアリングは,カチオンのオレフィン・ゴールド (Olefin-gold) コンプレックス (I) のイオンペアリングである
Daniele Zuccaccia1, Leonardo Belpassi, Francesco Tarantelli
1Dipartimento di Chimica, Università degli Studi di Perugia, Via Elce di Sotto, 8, 06123 Perugia, Italy.
Journal of the American Chemical Society
|February 18, 2009
まとめ
カウンテリオン (Counterion) とは
科学分野:
- 有機金属化学 有機金属化学
- 超分子化学 超分子化学
背景:
- アニオン-カタン相互作用は,有機金属複合体において極めて重要です.
- これらの相互作用を理解することは,触媒の設計と反応性に影響を与えます.
研究 の 目的:
- 金・ステレン複合体における相対アニオンカチオン指向を調査する.
- 補助リガンドがカウンテリオン位置づけにどのように影響するかを決定する.
主な方法:
- 利用したフッ素-19,プロトン-1核オーバーハウザー効果スペクトル (19F,1H-HOESY NMR).
- 密度関数理論 (DFT) の計算は,溶媒と相対論的効果を伴う.
主要な成果:
- [(PPh(3)) Au(4-Me-styrene) ]BF(4) では,BF(4)(-) アニオンは,フェニル群の反対側にあるオレフィン領域の近くにあります.
- [(NHC) Au ((4-Me-styrene) ]BF ((4) で,BF ((4) ((-) アニオンはN-ヘテロサイクリックカルベン (NHC) リガンドの近くにあります.
- カウンテリアンは,両方の複合体における金の中心から遠く離れている.
結論:
- カウンテリオンの位置は,補助リガンド選択で調整できます.
- この調節性により,触媒の特性および活性に対するより大きな制御が可能になります.
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