アルキンとアレンを金-シリコン結合に同挿入するメカニズム:包括的な実験/理論研究
Maximilian Joost1, Laura Estevez, Sonia Mallet-Ladeira
1Université de Toulouse, UPS, Laboratoire Hétérochimie Fondamentale Appliquée, 118 route de Narbonne, F-31062 Toulouse, France.
Journal of the American Chemical Society
|July 8, 2014
まとめ
この研究は,金-シリコン結合に金で触媒化されたアルキーンとアレンを挿入するメカニズムを明らかにしています. 反応は2段階の内球経路を経由し,動力学とDFT計算によって確認されます.
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:
- 金-シリコン複合体は,有機合成における多用途の中間物質である.
- アルキンおよびアレン挿入のメカニズムを理解することは,触媒設計に不可欠です.
研究 の 目的:
- アルキンとアレンをAu-Si結合にシン挿入する詳細なメカニズムを解明する.
- これらの変換におけるゴールドシリル複合体の役割を調査する.
- 観察された地域選択性を合理化するために,特に全体のために.
主な方法:
- 反応順序と熱力学的パラメータを決定するために,運動実験が行われました.
- 密度関数理論 (DFT) の計算を用いて,メカニズム的な経路を探求した.
- 計算的研究には,正確なアクティベーションエンタルピー推定のための分散修正 (B97D機能) が含まれていました.
主要な成果:
- この反応は,アルキンとゴールド・シリル複合体において,第1次反応であり,双分子結合メカニズムを示している.
- 2段階の内部球のメカニズムが提案された:アルキンの調整に続いて,速度を決定する移住の挿入.
- 理論的な活性化エンタルピー (11.5 kcal·mol−1) は,実験値 (13.7 kcal·mol−1) と密接に一致しました.
- 地域選択性は合理化され,異常なアレン挿入は,末端の二重結合挿入と,その後のAu/Siイソメリゼーションによって説明された.
結論:
- この研究は,ゴールドセンターにおける調整挿入メカニズムの有力な証拠を提供します.
- 内部球のメカニズムは,アルキンとアルレンの金シリル複合体による機能化のためにサポートされています.
- この発見は,シリコン基板を含む金触媒反応のより深い理解に貢献します.
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