ホモゲーヌス・ゴールド・カタリシスにおけるリガンド効果の有用性:地域分散型π-結合活性化サイクルを可能にする
Dong Ding, Tao Mou, Minghao Feng
1Shanghai Key Laboratory of Green Chemistry and Chemical Process, School of Chemistry and Molecular Engineering, East China Normal University , 3663 North Zhongshan Road, Shanghai, 200062, P. R. China.
Journal of the American Chemical Society
|April 9, 2016
まとめ
この研究は,アルキン水酸化に対する黄金触媒の精密な制御を示しています. リガンドの設計は地域選択性を決定し,複雑な分子合成のための選択的オーソまたはパラサイクリングを可能にします.
科学分野:
- 有機化学
- カタリシス
- ホモゲネス・カタリシス
背景:
- リガンドの性質は同質な触媒の結果に大きく影響する.
- アルキンの分子内ヒドロアリレーションにおける地域選択性の制御は,依然として課題である.
研究 の 目的:
- 電子とステリックリガンドの性質を全面的に利用することによってアルキンの地域分散型分子内水酸化を達成する.
- 選択的循環反応のための新しい催化剤を開発する.
主な方法:
- カチオン性Au (I) 触媒を用いて,それに合わせたフォスフィートとフォスフィンのリガンドを用いる.
- 柔軟な電子欠乏フォスフィートリガンドをオーソサイクライゼーションに使用した.
- パラサイクライゼーションのために固い電子豊富なフォスフィンリガンドを使用した.
- 複合的な構造を合成するための金/銀リレーの触媒過程を調査した.
主要な成果:
- フォスフィートリガンドとメトキシルアミド指向群を伴う3座標のカチオン Au ((I)) センターを使用してステリカルに阻害されたオーソポジションサイクリングを達成した.
- 固い電子豊富なフォスフィンリガンドベースのAu ((I)) 触媒によるパラポジションサイクリングのみで得られます.
- Au/Agリレーの触媒プロセスを通して,混雑した三循環構造を持つテトラヒドロピロキノリノンを合成した.
結論:
- 均質な金触媒における戦略的リガンド設計を通じてアルキン水酸化における地域選択性を制御する能力を示した.
- 多種多様なサイクル製品へのアクセスのための多用途な触媒システムを確立しました.
- 複雑な分子構造の構築における金と銀の触媒の相乗効果を強調した.
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