オルソ,オルソ'ダイアルキルフェニルアジドの光化学
Meng-Lin Tsao1, Matthew S Platz
1Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA.
Journal of the American Chemical Society
|September 25, 2003
まとめ
レーザーフラッシュ光分解により,代用されたフェニルアジドが単体および三重体ニトロンを形成する方法が明らかになった. 2,4,6-トリ-テルト-ブチルフェニルアジドのステリック阻害は,室温でユニークなベンザジリン形成につながります.
科学分野:
- フォトケミストリー フォトケミストリー
- 有機化学 オーガニック・ケミストリー
- スペクトル顕微鏡検査です.
背景:
- フェニルアジドは,有機合成において極めて重要な反応性中間物質であるニートレンの汎用的な前駆体である.
- 窒素の形成と反応性を理解することは,化学的変換を制御する上で鍵となる.
研究 の 目的:
- 様々な置換フェニルアジドの光物理的性質と反応経路を調査する.
- 異なる条件下でシングレット・ナイトレンとトリプレット・ナイトレンの形成と相互変換を解明する.
- ニトロンの反応性および中介物質の形成にステリウムの大量の影響を調査する.
主な方法:
- 266nmのレーザーフラッシュ光分解 (LFP) を用いて,ガラスのような3-メチルペンタンのフェニルアジドを77Kの温度で,環境温度でペンタンの温度で研究した.
- UV-VIS吸収スペクトロスコピーは,一時的な中間物質を検出し,特徴づけるために使用されました.
- 密度関数理論 (DFT) と分子軌道 (MO) の計算は,実験結果を解釈するのに役立ちました.
主要な成果:
- LFPは,研究されたすべてのアジドから一時的なシングレットナイトレンを生成し,それらは77 Kで持続的なトリプルレットナイトレンにリラックスした.
- シングレットからトリプルへのシステム間交差の速度定数は,低温で決定されました.
- 室温では,2,4,6-トリ-テルト-ブチルフェニルアジドは,より少ない阻害性アジドとは異なり,ディデヒドロアゼピン形成に先立ち,短命のベンザジリン中間物質を独特に形成しました.
結論:
- この研究は,フェニルアジドの光化学とニトロンの中間物質の行動に関する洞察を提供します.
- ステリック効果は反応経路に大きな影響を及ぼし,高度に置換されたアジドのベンザジリン形成を促進します.
- DFTとMOの計算は,観察された実験結果と提案されたメカニズムを裏付けます.
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