オレフィン-ボラン"ヴァン・デル・ワールズ複合体":挫折したルイス対加法反応における中間物質
Xiaoxi Zhao1, Douglas W Stephan
1Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada M5S 3H6.
Journal of the American Chemical Society
|July 21, 2011
まとめ
この研究では,ボーラン-オレフィン複合体は,加法反応の前にヴァン・デル・ワールスの相互作用によって形成されることを明らかにしています. これらの中間物質は,フォスフィン塩基と容易に反応して,周期性ズウィテリオン産物を作ります.
科学分野:
- 有機金属化学 有機金属化学
- 超分子化学 超分子化学
背景:
- 挫折ルイス対 (FLP) 化学には,容易に結合しないルイス酸と塩基が含まれています.
- 反応前の複合性を理解することは,FLPの反応性を制御するために極めて重要です.
研究 の 目的:
- FLP添加反応の前におけるボランとオレフィン間の初期相互作用を調査する.
- 特定の条件下で形成されるボラン-オレフィン複合体の性質を特徴付ける.
主な方法:
- (1) HOESYの低温 (−50°C) のNMRスペクトロスコーピーを利用した.
- 実験的観測をサポートするために計算モデリングを使用した.
- 結合されたルイス酸性ボランとビニル基を組み合わせたモデル化合物を合成した.
主要な成果:
- 実験データにより,ボリル基とビニル基の空間的接近が確認された.
- 計算による研究では,ヴァン・デル・ワールズのボラン・オレフィン複合体の形成が示されました.
- これらの複合体を,その後の添加反応における重要な中間物として特定した.
結論:
- ボラン・オレフィン・ヴァン・デル・ワールズ複合体は,FLP化学における一時的な中間物質である.
- これらの中間物質は,フォスフィン塩基との容易な添加反応を経験します.
- 周期性ズウィテリオン産物の形成は,これらのプレコンプレックスイベントによって促進されます.
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