固体/固体有機反応の理解
G Rothenberg1, A P Downie, C L Raston
1York Green Chemistry Group, Chemistry Department, University of York, Heslington, York YO10 5DD, UK.
Journal of the American Chemical Society
|September 6, 2001
まとめ
ほとんどの固体相有機反応は,固体反応物を研磨することで形成される液相を含んでいる. このユーテクティックな混合物形成は反応運動を説明し,真の固体相反応の概念に異議を唱える.
科学分野:
- 有機化学 オーガニック・ケミストリー
- マテリアルサイエンス 材料科学
- 物理化学 物理化学
背景:
- 固体粒子の間の有機反応を調査することは,新しい合成方法論の開発に不可欠です.
- 多くの反応が固体相で起こることが報告されていますが,そのメカニズムは明確にする必要があります.
研究 の 目的:
- 固体相有機反応の概念を調査する.
- 固体反応物の間の反応における相変化の役割を決定する.
主な方法:
- 19件の報告された"固体相"有機反応の分析.
- 固体反応物の機械的混合 (研磨) を行う.
- 相変化 (液化) と反応運動学の観察.
主要な成果:
- 固体反応物質を研磨すると,通常は液体相を形成し,通常は周囲の温度より低い融点を持つエウテクティック混合物になります.
- この液化は,アルドール凝縮,ベイヤー-ヴィリガー酸化,芳香ブロミネーションを含む,触媒的および非触媒的反応の両方で発生します.
- 観測された反応動態は,固体相から液体相への移行によって説明される.
結論:
- マクロスコープの粒子の間の真の固体相反応は稀であり,液化は一般的な現象である.
- ユーテクティックまたはペリテクティック形成は,固体反応物の機械的混合を含む反応を理解するための鍵です.
- 固体反応剤を含む反応性システムの一般的なモデルは,潜在的な液相形成を考慮する必要があります.
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