Cu(I) とダイアルキルペロキシドの反応: Cu(II) -アルコキシド,アルコキシラジカル,および触媒C-Hエーテル化
Raymond T Gephart1, Claire L McMullin, Nicholas G Sapiezynski
1Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, USA.
Journal of the American Chemical Society
|September 27, 2012
まとめ
銅 ((I) 触媒は tert-ブチル水酸化物の活性化を促進し, tert-ブトキシル基を生成する. これらのラジカルは,軽度な条件下でサイクロヘクサンの効率的な触媒C-Hエーテル化を可能にします.
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
- ラジカル・ケミストリー (Radical Chemistry) とは
背景:
- 銅 ((I) 複合体は,有機合成における汎用的な触媒である.
- 酸化過酸化物の活性化は,反応性根幹種を生成するために重要である.
- C-H機能化は,貴重な有機化合物への直接的な経路を提供します.
研究 の 目的:
- 銅(I) β-ジケチミネートと有機過酸化物との反応機構を調査する.
- アルコキシラジカルの生成と反応性を調査する.
- 銅と過酸化物を用いたC-Hエーテル化のための触媒システムを開発する.
主な方法:
- 銅の運動分析 (I) 複合反応で,テルトブチル水酸化物とディキュミル過酸化物.
- 酸化過酸化物の活性化経路を明らかにするための計算モデリング.
- サイクロヘキサンとテルトブチル水酸化物を用いた触媒C-Hエステル化実験.
主要な成果:
- 酸化過酸化反応の第一次動力学が観察され,自由基の形成を示しています.
- 新しいペロキシド銅添加物と一時的なCu (III) 種を特定する.
- サイクロヘキサンのC-H触媒エーテル化が成功し,室温で60%の特ルートブチルサイクロヘキシルエーテルが得られました.
結論:
- 銅 (((I) 複合体は,有機過酸化物を根幹経路で効果的に活性化する.
- 生成されたテルトブトキシルラジカルは,触媒的なC-Hエーテル化のために活用することができます.
- この研究は,エーテルを合成するための新しい効率的な方法を示しています.
関連する概念動画
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Baeyer–Villiger oxidation converts aldehydes to carboxylic acids and ketones to esters. The reaction uses peroxy acids or peracids and is often catalyzed by acid. The reaction is named after its pioneers, Adolf von Baeyer and Victor Villiger. The reaction is achieved by a wide range of peracids such as m-chloroperoxybenzoic acid (mCPBA), perbenzoic acid (C6H5COOOH), peracetic acid (CH3COOOH), hydrogen peroxide (H2O2), and tert-butyl hydroperoxide (t-BuOOH).
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