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銅 ((I) /TEMPO触媒によるエアロビックアルコール酸化のメカニズム
Jessica M Hoover1, Bradford L Ryland, Shannon S Stahl
1Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA.
Journal of the American Chemical Society
|January 16, 2013
まとめ
この研究では,エアロビックアルコール酸化のための銅/TEMPO触媒システムを調査しています. このメカニズムは,ベンジルアルコールとアリファートアルコールの異なる速度制限ステップを明らかにし,触媒設計の洞察を提供します.
科学分野:
- カタリシス カタリシス カタリシス
- 有機化学 オーガニック・ケミストリー
- 酸化反応は,酸化反応によって起こる.
背景:
- 均質な銅/TEMPO (2,2,6,6-テトラメチルピペリジン-N-オキシル) 触媒は,エアロビックアルコール酸化に有効である.
- 以前報告された (bpy) Cu(I) /TEMPO/NMI (N-メチリミダゾール) システムは,活性化されていないアルコールであっても,高い割合と選択性を示しています.
研究 の 目的:
- (bpy) Cu(I) /TEMPO/NMI触媒システムのメカニズム調査を実施する.
- ベンジルアルコールとアリファートアルコールの反応性とメカニズム経路を比較する.
主な方法:
- ガス吸収とインシット赤外線光譜を用いた運動分析.
- EPRと紫外線可視光譜を用いた触媒特異の特徴化.
- 動的同位体効果の評価. イソトープ効果の評価.
主要な成果:
- 2段階の触媒機構が解明された: O2による触媒酸化と基板酸化.
- 触媒の酸化には二核Cu(2) O(2) の中間物質が含まれる.
- 基板の酸化は,Cu (II) とTEMPOのニトロキシル基経由で進行し,Cu (II) -アルコキシド中間体が含まれています.
結論:
- ベンジルアルコールの酸化とアリファティックアルコールの酸化は,ターンオーバーを制限する異なるステップを示します.
- O2による触媒の酸化は,ベンジルアルコールの速度を制限する.
- アリファティックアルコール酸化の回転率には,複数のステップが貢献しています.
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