アミン-ボランの鉄触媒による脱水結合/脱水化
James R Vance1, André Schäfer, Alasdair P M Robertson
1School of Chemistry, University of Bristol, Cantock's Close , Bristol BS8 1TS, U.K.
Journal of the American Chemical Society
|February 18, 2014
まとめ
鉄カルボニル複合体は,アミン-ボランの脱水結合をシクロディボラザンに効率的に触媒化する. 鉄前触媒1と2では異なるメカニズムが観察され,ナノ粒子の形成が触媒活性に影響する.
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
- マテリアルサイエンス 材料科学
背景:
- 鉄カルボニル複合体は,容易に入手可能で,多用途の前触媒である.
- アミンボランは,材料合成の重要な前駆体である.
- デヒドロカップリング反応は,貴重な循環化合物への経路を提供します.
研究 の 目的:
- アミン-ボラン脱水結合の前触媒としての鉄カルボニル複合体の有効性を調査する.
- 触媒サイクルに関与するメカニズム的経路を解明する.
- 活性触媒種の性質,均質または異質を調査する.
主な方法:
- アミン・ボランのUV光照射を鉄カルボニル前触媒で行う.
- 反応のモニタリングのためのin situ (11) B NMRスペクトロスコーピー.
- 機械的調査のための実験的および計算的DFT研究.
主要な成果:
- 鉄カルボニル複合体 [CpFe(CO) ]2 (1) とCpFe(CO) 2I (2) は,Me2NH·BH3 (3) から効率的に生成されたサイクロディボラーゼン [Me2N-BH2]2 (4) を効率的に生成した.
- 前催化剤1と2では,異なる中間物質を含む2段階の明確なメカニズムが特定されました.
- より活発な触媒であるCp2Fe2(CO) 3(MeCN) (7) は,鉄ナノ粒子 (異質) を形成し,光活性化を必要としなかった.
- 前触媒2は均質な活性触媒を生み出し,前触媒1は光照射で異質なナノ粒子を形成した可能性が高い.
結論:
- 鉄カルボニル複合体は,アミン-ボラン脱水結合の効果的な前触媒として機能する.
- 触媒機構と活性種の性質 (均質か異質か) は,特定の鉄前触媒に依存する.
- 鉄ナノ粒子の形成は,これらの脱水結合反応における触媒活性を大幅に高めることができます.
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