アリルエーサーの水素分解のための異質なニッケル触媒,アレン水素化なしでアリルエーサーを水素化する
Alexey G Sergeev1, Jonathan D Webb, John F Hartwig
1Department of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, United States.
Journal of the American Chemical Society
|November 21, 2012
まとめ
新しい異質ニッケル触媒は,アリルエーテルを効率的にアレンとアルコールに分割します. この触媒は温和な条件下で動作し,芳香環水素化なしでリグニンモデル化合物の変換のための選択的な経路を提供します.
科学分野:
- カタリシス カタリシス カタリシス
- 有機金属化学 有機金属化学
- グリーン・ケミストリー (Green Chemistry)
背景:
- リグニンに多く含まれているアリルエーサーは,バイオマス価値化に課題をもたらす.
- アリルエーテル結合の選択的分裂は,リグニンを有価な化学物質に変換するために不可欠です.
- 既存の方法は,しばしば厳しい条件を必要とし,選択性が欠けている.
研究 の 目的:
- 選択的アリルエーテル水素分解のための新しい異質なニッケル触媒を開発する.
- 温和な条件下 (低圧,低温) で触媒の性能を調査する.
- 異質な触媒の選択性を,以前に報告された同質なシステムと比較する.
主な方法:
- 溶解性前体 (Ni(COD) ((2) またはNi(CH2TMS) ((2(TMEDA)) から,塩基添加物 ((t) BuONa)) を含む異質なニッケル触媒のインシット生成.
- アリルエーテルモデル化合物の水解における触媒の活性と選択性のテスト.
- 低負荷 (0.25 mol %) と低水素圧力 (1 bar) で触媒の性能を評価する.
主要な成果:
- 異質なニッケル触媒は,アリルエーテル内のC(Ar) -O結合を選択的に割ってアレンとアルコールを生成します.
- この反応は,芳香環の水素化なしに進行する.
- 触媒は,低負荷 (0.25 mol %) と1バーのH2圧で高効率を示しています.
- 触媒は,以前に報告された均質ニッケル触媒と比較して,明確な選択性を示しています.
結論:
- アリルエーテル水解のための頑丈で選択的な異質ニッケル触媒が成功裏に開発されました.
- この触媒は,軽度で持続可能な条件下で,リンニン由来化合物の価値化のための有望な経路を提供します.
- 選択性の観察された差異は,異質的および均質の触媒システムの独特な性質を強調しています.
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