ボランによってH-HとSi-H結合が容易に活性化される
Georgii I Nikonov1, Sergei F Vyboishchikov, Oleg Sherbrooke
1Chemistry Department, Brock University, St. Catharines, Ontario, Canada. gnikonov@brocku.ca
Journal of the American Chemical Society
|March 8, 2012
まとめ
ボラン B ((C ((6) F ((5)) ((3))) 前催化剤は,HB ((C ((6) F ((5)) ((2)) に変換することによってシランにH/Dの交換を促進し,これは σ-結合メタテシスを通じてH-HとSi-H結合を活性化します.
科学分野:
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
- シラン化学 シラン化学
背景:
- ボランは,触媒における多用途な化合物である.
- H/D交換反応は,力学的な研究において極めて重要です.
- ディヒドロゲン活性化は,触媒における課題であり続けています.
研究 の 目的:
- H/D交換反応におけるB,C,F,C,F,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C, where where where where where where where where where where where where where where where where where where where where where where where known known known known known known known known known known known known known as known as known as known as known as known as known as known as known as known as known
- ボランによる二水素活性化のメカニズムを解明する.
- H/D交換プロセスにおける活性触媒種を特定する.
主な方法:
- ボランとデュテリウムラベル付きシランを対象とした実験研究.
- 密度関数理論 (DFT) による計算.
- 反応モニタリングと製品分析.
主要な成果:
- B ((C ((6) F ((5)) ((3) は,活性種ではなく,前触媒として作用する.
- ハイドロシランはB (C) をHB (C) に変換する.
- HB (((C ((6))) F ((5)) ((2)) は, σ-結合メタテシス経由で H-H と Si-H 結合を活性化する.
結論:
- 活性触媒はHB (C6F5)) (2) で,in situで形成される.
- このメカニズムは,H/D交換のための σ-ボンドメタテシスを含む.
- この研究は,二水素活性化とH/D交換におけるボランの役割を明らかにしています.
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