オゾノイド,エポキシド,およびC ((70) のオキシドアヌレンのオゾノイド
Dieter Heymann1, Sergei M Bachilo, R Bruce Weisman
1Department of Earth Science, Rice Quantum Institute, Rice University, Houston, Texas 77251, USA.
Journal of the American Chemical Society
|May 30, 2002
まとめ
研究者らは,新しい酸素添加物を作るため,C70をオゾン化しました. これらのオゾニドは,熱分解または光分解によって,エポキシドおよびオキシドアヌルレンを含む様々なC(70) Oイソマーに変換されます.
科学分野:
- フラーレン 化学 フラーレン化学
- 有機化学 オーガニック・ケミストリー
- フォトケミストリー フォトケミストリー
背景:
- C70のようなフルレンは,ユニークな電子的および構造的性質を持つ炭素のアロトロップである.
- フラーレンの酸素種との反応は,その化学反応性と潜在的な応用を理解するために重要である.
- 以前の研究では,C ((60)) のオゾン化が調査されており,C ((70) の反応と比較するための基礎を提供している.
研究 の 目的:
- 酸素種を用いた新種のC ((70) のモノアダクトを合成し,特徴づけること.
- C(70) オゾノイドの熱的および光化学的変換を調査する.
- C(70) オゾニドの反応性とC(60) の反応性を比較する.
主な方法:
- C ((70) 溶液をオゾン化してオゾン化モノアダクトを形成する.
- 発生したC(70) 酸素添加物の分離と特徴付け.
- オゾノイドの分解経路を研究するための熱分解と光分解の実験.
主要な成果:
- 酸素を含む6つの新しいC ((70) のモノアダクトが成功裏に準備され,特定されました.
- 最初の2つのオゾニドモノアダクト,a,b-とc,c-C(70) O(3) が形成された.
- これらのオゾニドの熱分解と光分解により,エポキシドとオキシドアヌレンを含むC(70) Oの様々な同位体が得られた.
- a,b-C(70) O(3) 同位体は,熱分解時にエポキシドと光分解時にオキシドアヌレンを選択的に形成した.
- c,c-C(70) O(3) 同位体は,異なる熱および光化学的産物を示し,熱分解によりオキシドアヌレンの生成,光分解によりオキシドアヌレンの混合物と少量のエポキシドが生成された.
- 特定されたすべてのC(70) Oオキシドアヌレンのイソマーは,エポキシドへの光イソメリゼーションを受けることが判明しました.
結論:
- C ((70) のオゾン化により,さまざまな酸素化されたフルレン誘導体へのアクセスが可能になります.
- C(70) オゾニドの独特の熱および光化学的経路は,立体化学が反応性に影響することを強調しています.
- 観察されたC(70) オゾニドの反応はC(60) オゾニドの反応に並行しており,フルレンのオゾノリシスの一般的なメカニズムを示唆しています.
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