c60の急性反応は,c60の急性反応である

P J Krusic, E Wasserman, P N Keizer

Science (New York, N.Y.)

|November 22, 1991

まとめ

ベンジルとメチルラジカルは,C ((60)) フルレンに素早く加わります. ESRスペクトロスコーピーで特定された安定系アダクトは,置換物によって保護された局所的なペアレス電子を示します.

科学分野:

フラーレン化学フラーレンの化学
ラジカル・ケミストリー (Radical Chemistry) とは
フォトケミストリーフォトケミストリー

背景:

フーラーレン,特にC ((60)) は,ユニークな電子特性を有する炭素アロトロップである.
ラジカル添加反応は,フルレネの機能化に不可欠である.
光化学的方法は,反応性種の制御された生成を提供します.

研究の目的:

ベンジルおよびメチルラジカルの光化学的添加をC(60) フルレレンに調査する.
結果として生じる根源的および非根源的アダクトを特徴づける.
これらのアダクトの安定性と電子特性を理解するために.

主な方法:

ベンジルおよびメチルラジカルの光化学生成.
ラジカルとC ((60)) の反応.
電子スピン共振 (ESR) スペクトロスコピーと質量スペクトロメトリを用いた特徴付け.

主要な成果:

ベンジル基添加物 (RnC(60) の形成は,n=1から少なくとも15までである.
ESRによる安定したアリル基 (n=3) とサイクロペンタディエニル (n=5) ベンジル基アダクトの特定.
n=1から少なくとも34までのメチルラジカル添加物 ((CH3) nC ((60)) の形成,質量スペクトロメトリーで分析.

結論:

ベンジルとメチルラジカルは,光化学的条件下でC (−60) に効率的に加わります.
ベンジル基によるステリック保護は,急性添加物の安定性に寄与する.
安定アダクトのペアレス電子は,C ((60)) 表面に位置しています.

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