Fe/Ru/Os-bis(arene) 複合体のリングスリップとマルチ電子還酸化特性:ハプティシティの変化は本当に潜在的逆転を引き起こすのか?
Richard L Lord1, Cynthia K Schauer, Franklin A Schultz
1Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States.
Journal of the American Chemical Society
|September 8, 2011
まとめ
グループ8の金属のビス ((ヘクサメチルベンゼン) 複合体は,多様な電子伝送機構を示している. 結合によって引き起こされるハプティシティの変化は,これらの移行金属化合物の表面的なマルチ電子の振る舞いを制御する.
科学分野:
- 有機金属化学 有機金属化学
- 無機化学 無機化学とは
- 電気化学 電気化学について
背景:
- グループ8bis ((ヘクサメチルベンゼン) 金属複合物 (Fe,Ru,Os) は,さまざまな酸化還元反応を示しています.
- 電子伝送メカニズムと熱力学は,M(II) →M(I) →M(0) シリーズにおいて著しく異なる.
- 以前の推測では,Fe (((0) のハプティシティが連続的な電子移転と関連していた.
研究 の 目的:
- グループ8 bis ((ヘクサメチルベンゼン) 複合体の電子伝送機構を調査する.
- レドックス行動の制御におけるハプティシティの変化の役割を明らかにする.
- d(6) bis((arene) レドックス化学を理解するための概念モデルを開発する.
主な方法:
- 密度関数理論 (DFT) の計算が採用されました.
- 確立されたモデル化学が利用されました.
- 電気化学実験が行われました.
主要な成果:
- Fe複合体は異なる酸化還元電位を示し,Ruは重複する電位を示し,Osは2電子の移転を示している.
- ハプティシティの変化は結合の結果であり,電子の結合に影響を与えます.
- 推奨されるFe(0) 状態は,提案された η(4):η(6) ではなく,三重 η(6):η(6) である.
- RuとOsは,ハプティシティの変化が起こる時に基づいて異なるメカニズムを使用します.
結論:
- ハプティシティの変化だけでは,マルチ電子の振る舞いを保証するものではありません.
- 垂直の電子結合は,明らかな多電子還酸化現象を決定する.
- Feトライアードを超えて適用可能な,d(6) bis(arene) レドックス行動の一般的なモデルが確立されました.
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