周期性α-ディアゾカルボニル化合物のRh触媒による分子間反応は,三次性C-H結合移動に対する選択性を持つ
Andrew DeAngelis1, Olga Dmitrenko, Joseph M Fox
1Brown Laboratories, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA.
Journal of the American Chemical Society
|June 9, 2012
まとめ
新しいRh触媒反応は,周期性ダイアゾカルボニル化合物を用いて選択的な分子間変換を可能にします. これらの方法はステリック障害を克服し,サイクロプロパネーションとX-H挿入を様々な基板で容易にします.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
背景:
- 化学選択反応は有機合成において極めて重要です.
- Rh-カルベノイドは多用途の中間物質ですが,β-ヒドリド除去などの競合する経路に対する選択性の課題に直面することがよくあります.
研究 の 目的:
- 循環性α-ディアゾカルボニル化合物の新しい分子間Rh触媒反応を開発する.
- β-ヒドリド除去に対する化学選択性を達成するために.
- これらの新しい変容の範囲と限界を探求する.
主な方法:
- 循環性α-ディアゾカルボニル化合物をRh-カルベノイドの前駆体として利用した.
- サイクロプロパネーション,サイクロプロペネーション,X-H挿入を含む研究された分子間反応.
- 機械論的提案をサポートするためのDensity Functional Theory (DFT) の計算. 機械論的提案をサポートする.
主要な成果:
- 第一の一般的分子間Rh-カルベノイド反応が,三次性β-C-H結合移動に対して選択的であることを実証した.
- 幅広い基板で成功した変換を達成しました.
- 反応性に影響するステリックおよびコンフォーマーションの要因を特定し,特に7つの環の反応性に影響した.
結論:
- 循環性α-ディアゾカルボニル化合物,特に5つまたは6つ環は,カルベンの結合を強化することによって,分子間Rh触媒反応を促進します.
- より大きな環のステリックおよび構成的柔軟性は,分子間反応性を阻害する可能性があります.
- 開発された方法は,選択的有機合成のための強力な新しいツールを提供します.
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