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パラジウム (II) 水酸化物,フェノキシド,アルコキシド複合体の水素分解
Gregory R Fulmer1, Alexandra N Herndon, Werner Kaminsky
1Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, United States.
Journal of the American Chemical Society
|September 22, 2011
まとめ
この研究では,パラジウム-酸素結合の水素分解を調査するために,パラジウム複合体を合成しました. 水素分解の選択性は,酸化アルコシドリガンドによって達成され,金属アルコシドの反応経路が明らかにされました.
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:
- パラジウム-酸素結合は,様々な触媒過程における重要な中間物質である.
- パラジウムアルオキシドとアリオキシドの反応性を理解することは,触媒的結果の制御の鍵です.
- 水素分解は,触媒に重要なパラジウム水化物種への直接的な経路を提供します.
研究 の 目的:
- ピンチャーパラジウム ((II) -OR) コンプレックスの一連の合成と特徴づけ.
- パラジウム-酸素結合のための水解反応の一般性と選択性を探求する.
- パラジウムアルコキシドとアリオキシドの反応性を影響する要因を解明する.
主な方法:
- 多種多様なR群を持つピンサー ((tBu) PCP) Pd ((II) -OR複合体の合成.
- 異なる条件下での水解反応の調査.
- 水解とβ-ヒドリド抽出を含む競合する反応経路の分析.
主要な成果:
- パラジウム水酸化物の水解は,ダイマー形成によって阻害された.
- アルコキシドパラジウムとアリロキシドの反応性は,リガンドの固体性および電子性,およびβ-水素の存在によって異なる.
- 水解とβ-ヒドリド抽出は,多くの基質の水解を複雑にしました.
- 水素分解に対する高い選択性は,フッ素化2フッ素酸化物リガンドで達成された.
結論:
- 遅い移行金属アルコキシドの反応性は調節可能である.
- リガンドの設計は,パラジウム-酸素結合の反応性を水素分解のような望ましい経路に誘導するために重要である.
- 部分的に酸化アルコシドリガンドは,選択的水解反応の有望性を示しています.
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