リガンド基板分散は,活性化されていないオレフィンの銅触媒化水酸化を促進する
Gang Lu1, Richard Y Liu2, Yang Yang2
1Department of Chemistry, University of Pittsburgh , Pittsburgh, Pennsylvania 15260, United States.
Journal of the American Chemical Society
|October 25, 2017
まとめ
研究者らは,リガンドと基板の間の魅力的な分散相互作用が,銅で触媒化された水酸化反応の反応性を高めることを発見した. P- アリル基を持つ大量フォスフィンリガンドは,この改善された触媒性能の鍵です.
科学分野:
- 有機金属化学
- カタリシス
- コンピュータ化学
背景:
- 移行金属触媒におけるリガンド効果は,通常,透き通る結合と透き通る空間相互作用によって説明され,後者はしばしば排斥的に見られる.
- リガンドと基板の間の分散力など,魅力的な非共性相互作用は,過渡金属触媒ではめったに考慮されません.
- これらの相互作用を理解することは より効率的な触媒の設計に不可欠です
研究 の 目的:
- 触媒と基板の相互作用を定量的に評価するための計算モデルを開発する.
- 銅 (I) 水化物 (CuH) 触媒化水酸化におけるリガンド-基板分散相互作用の役割を調査する.
- 大量バイデント酸フォスフィンリガンドで観察された反応性の増加の起源を明らかにする.
主な方法:
- 触媒と基板の相互作用を分析するための計算モデルの開発.
- このモデルの適用は,銅 ((I) ハイドリド触媒による非活性化オレフィンの水素アミネーションです.
- 様々なフォスフィンリガンドを用いた運動研究による検証
主要な成果:
- 計算モデルでは,触媒と基板の相互作用を定量的に分析した.
- CuH触媒による水酸化における反応性の強化は,魅力的なリガンド- 基板分散相互作用から生じる.
- 特にP- アリル基を持つ大容量バイデント酸フォスフィンリガンドは,反応速度を大幅に高めます.
結論:
- 分散相互作用は,過渡金属の触媒化において,しばしば見過ごされる重要な役割を果たします.
- CuH触媒化水酸化におけるボリュックなフォスフィンリガンドの性能の向上は,有利なリガンド-基板分散力によるものである.
- 大量のP-アリル群を組み込むリガンドの戦略的設計は,触媒効率を最適化することができます.
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