アリシランの酸化に関するメカニズム的研究F NMRスペクトロスコーピー
Elizabeth J Rayment1, Aroonroj Mekareeya1, Nick Summerhill2
1Chemistry Research Laboratory, University of Oxford , 12 Mansfield Road, Oxford, OX1 3TA, United Kingdom.
Journal of the American Chemical Society
|April 20, 2017
まとめ
この研究では,フッ素-19核磁気共振 (F NMR) 光譜を用いてアリシランをフェノールに酸化することを明らかにした. この反応メカニズムでは,五価ペロキシドの中間物質が速度を制限するアリル移行に先行する.
科学分野:
- オルガノシリコン化学
- 反応機構の解明
- スペクトル分析
背景:
- アリルシランの酸化は有機合成における重要な変換である.
- 反応メカニズムを理解することは,収穫量と選択性を最適化するために不可欠です.
- 以前の研究では,アリシランからフェノールへの変換に関する詳細なメカニズムが欠けていました.
研究 の 目的:
- アリシランをフェノールに酸化する詳細な反応機構を調査する.
- 主要な中間要素とレートを決定するステップを特定する.
- 置換電子効果と反応運動を相関させる.
主な方法:
- 反応のモニタリングのためにフッ素-19核磁気共鳴 (F NMR) スペクトロスコーピーを利用した.
- 種の反応率を評価するために,濃度プロフィールの運動モデルを使用した.
- 初期フェノール形成率と代替電子効果を研究した.
主要な成果:
- 五価ペロキシドエイト複合体の 迅速かつ可逆的形成を特定した.
- アリル移動が全体的なメカニズムで速度を制限するステップであることを決定しました.
- シラノール形成におけるシラノール/アルコキシシランの均衡の役割を確立した.
結論:
- アリシランをフェノールに酸化するための包括的なメカニズム図が確立されています.
- この発見は,オルガノシリコンの反応経路に関する重要な洞察を提供します.
- この研究は,複雑な反応のモニタリングにおける19F NMRスペクトロシーの有用性を強調しています.
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