オキシボリル複合体:プラチナの協調球で安定したボロン-酸素三重結合
Holger Braunschweig1, Krzysztof Radacki, Achim Schneider
1Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany. h.braunschweig@mail.uni-wuerzburg.de
Science (New York, N.Y.)
|April 17, 2010
まとめ
研究者らは,室温で最初の安定したオキシボリル複合体,トランス-[(Cy3P) 2BrPt(B[トリプル結合]O) の形成を報告した. このプラチナに結合したボロン-酸素種は,ユニークな三重結合を示し,様々な条件下で分解に抵抗します.
科学分野:
- 無機化学 無機化学とは
- 有機金属化学 有機金属化学
- ボロン化学 ボロン化学
背景:
- モノメリックオックスボランは,典型的には一時的な種であり,特殊なガス相または低温マトリックス分離実験でのみ観察される.
- 異常な結合機構を備えた安定化合物の合成と特徴づけは,無機化学における重要な課題であり続けています.
研究 の 目的:
- 室温で安定したモノメリックオクソボリル複合体を合成し,特徴づけること.
- 複合体内のボロン-酸素結合の存在と性質を確認するために.
主な方法:
- トロウエール溶液中の[Pt(PCy3) 2とジブロモ[トリメチルシロキシ]ボランの反応.
- スペクトロスコーピック方法 (例えば,NMR,IR) とX線微分分析を用いた特徴化.
- 結合特性を分析するための計算研究.
主要な成果:
- トリメチルシリルブロミドの可逆的除去による安定したオキシボリル複合体のトランス-[[(Cy3P) 2BrPt(B[トリプル結合]O) ]の形成.
- 複合体は,光分解および熱ストレス下でも,オリゴメリゼーションに対する惰性を示した.
- ブロミドをチオフェノラートに置き換えると,関連する複合体が生み出され,構造的割り当てをさらに支持しました.
- 実験データと計算データにより,ボロン-酸素のトリプル結合が確認され,B-O距離が短い (120.5~7分) と結合の縮小が示されました.
結論:
- 安定したモノメリックオキシボリル複合体は,環境条件下で合成され,分離することができます.
- この研究は,プラチナで安定したボロン-酸素三重結合の有力な証拠を提供します.
- この研究は,ボロン-酸素化合物の既知の化学を拡張し,異常な結合に関する洞察を提供します.
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