3座標のCo (I) は不飽和の二酸化水素-Co (III) と7座標のCo (V) にアクセスを提供する
Michael Ingleson1, Hongjun Fan, Maren Pink
1Department of Chemistry and Molecular Structure Center, Indiana University, Bloomington, IN 47405, USA.
Journal of the American Chemical Society
|February 9, 2006
まとめ
新しいコバルト複合体PNPCoは,素早く水素と反応して三価コバルト水化物を形成する. また,シランと反応してユニークなコバルト ((V) シリレン化合物を生成し,新しい反応性を示しています.
科学分野:
- 有機金属化学 有機金属化学
- 協調化化学について
- シリコン化学 シリコン化学
背景:
- 3座標のT形コバルト ((I) 複合体は,不飽和な性質のため,ユニークな反応性を持っています.
- 新種の低価変異金属複合体の合成と特徴づけは,基本的な化学変化を理解するために極めて重要です.
研究 の 目的:
- 新しい3座標のT形コバルト (I) 複合体,PNPCo.を合成し,特徴づけること.
- PNPCoの反応性を,H2や原始シラネスなどの小分子と研究する.
- コバルト複合体における異常な酸化状態と結合モチーフの形成を調査する.
主な方法:
- PNPCo.Cl.のマグネシウム還元によるPNPCoの合成
- PNPCoが分子水素 (H2) と反応する.
- PNPCoがプライマリシラン (PhSiH3) と反応する.
- 放射光学および分析技術を用いた結果のコバルト複合物の特徴化.
主要な成果:
- 三重 (S=1) コバルト (I) 複合体であるPNPCoが成功して合成されました.
- PNPCoは,H2との熱的に可逆的な酸化添加を経て,三価コバルト水化物,PNPCo ((H) 2.2) を形成する.
- 過剰なPhSiH3との反応により,塩基安定したシリレンコバルト (V) 化合物, {kappa2-tBu2PCH2Me2SiNSiMe2CH2tBu2P (H) Si=}Co (H) 3 (SiH2Ph) 2が生じる.
結論:
- 不飽和コバルト (I) 複合体PNPCoは,小分子に対する多用途の反応性を表しています.
- PNPCoは,高価コバルト種と新種のシリレン複合物の形成を促進します.
- この研究は,低価コバルト複合体とその変換の既知の化学を拡張します.
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