分子間エニンメタテシスのメカニズムに関する研究:運動方法とアルキン置換剤効果
Brandon R Galan1, Anthony J Giessert, Jerome B Keister
1Department of Chemistry, University at Buffalo, the State University of New York, Buffalo, New York 14260-3000, USA.
Journal of the American Chemical Society
|April 21, 2005
まとめ
エニンの転移率はアルキンの置換で増加する. この研究は,アルキリデン先のメカニズムを示唆し,特定の反応の速度制限としてビニルカルベンの中間物質を特定しています.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- 反応の動力学
背景:
- エニネ・メタテシスは,強力な炭素-炭素結合形成反応である.
- 触媒プロセスを最適化するために,その運動学を理解することは極めて重要です.
研究 の 目的:
- エニネメタテシスの反応運動を調査する.
- 特定のアルキン-アルケンの交叉メタテシス反応の速度法則を決定する.
主な方法:
- 反応の進行を監視するために,赤外線 (IR) スペクトロスコーピーを用いた.
- アルキン-エチレンとアルキン-1-ヘクセンのクロスメタテシスを含む様々なアルキン-アルケンの組み合わせについて,運動学的研究が行われました.
主要な成果:
- 反応速度は,アルキンの置換量が増えると増加することが判明しました.
- プロパルギルエステルによるケレーションは,反応速度に影響を与える重要な要因として除外されました.
- 炭化水素アルキンとの比率比較は,ケレーション効果の排除を支持した.
結論:
- この発見は,アルキリデンの最初の反応メカニズムを支持する.
- フォスフィンに結合したルテニウムカルベンの種は,休息状態として識別されました.
- ビニルカルベンの中間物質は,アルキン-1-ヘクセンメタテシスの速度を決定するステップとして関与していた.
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