SmI2の反応における触媒Ni (II) 反応: Sm (II) -またはNi (0) ベースの化学反応
Kimberly A Choquette1, Dhandapani V Sadasivam, Robert A Flowers
1Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, USA.
Journal of the American Chemical Society
|May 31, 2011
まとめ
触媒ニッケル (((II) 塩は,ニッケル (((0) に還元することによって,サマリウムバービエの反応を強化する. このニッケル ((0) は,酸化添加による反応を駆動し,この過程の基礎にある既知のニッケル化学を明らかにします.
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
- 反応メカニズム 反応メカニズム
背景:
- サマリウムダイオイド (SmI2) は,有機合成で使用される多用途の還元剤です.
- 触媒量のNi (II) 塩は,SmI2媒介反応における反応性と選択性を高めることが知られている.
- SmI2反応におけるNi (II) 触媒のメカニズム的基礎は,まだ十分に理解されていない.
研究 の 目的:
- サマリウムバルビエ反応における触媒Ni (II) のメカニズム的役割を解明する.
- 反応条件下でNi(II) とSmI2の相互作用を調査する.
- 活性触媒種と反応経路を決定する.
主な方法:
- 中間物質を特定するためのスペクトロスコピック研究 (例えば,UV-Vis,EPR)
- 反応速度と順序を決定するための運動測定.
- 反応経路を追跡するための同位体ラベリング研究.
主要な成果:
- サマリウムバービエの反応は,速度を制限するステップでNi (II) をNi (II) に還元することによって引き起こされる.
- 生成されたNi(0) は,アルキルハリド結合に酸化添加され,オルガンニッケル種を形成します.
- コロイドのNi ((0) の同時形成は非生産的な副作用として観察されました.
結論:
- SmI2/Ni(II) バービエ反応における反応性と選択性の強化は,主に既知のNi(0) 化学によるものである.
- 反応メカニズムは,独特のSmI2特性ではなく,Ni(II) をNi(0に還元し,その後に酸化添加を加える.
- この研究は,触媒効果を既知のニッケル媒介プロセスに再帰している.
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