[2,2](5,8) ピセノファネディエン:合成,構造分析,分子動力学,および可逆性内分子構造変換
Min-Chih Tang1, Yu-Chen Wei2, Yen-Chen Chu1
1Department of Chemistry, National Cheng Kung University, 70101 Tainan, Taiwan.
Journal of the American Chemical Society
|November 19, 2020
まとめ
研究者はダイブロモフェン誘導体の効率的な合成を開発し,新しいピケノファンを生み出した. これらの分子は,構造的変異の影響を受けた二重放出とエクシマー形成を含むユニークな光物理的特性を表しています.
科学分野:
- 有機化学
- 超分子化学
- フォト物理学
背景:
- ピケンの微分は,その大きな π システムのために興味深い.
- 複雑なポリサイクル芳香炭化水素の構造と性質の関係を理解することは極めて重要です.
研究 の 目的:
- 機能化されたピセンの前駆体への効率的な合成経路を開発する.
- 新しいピケノファンの誘導体を合成し,特徴づけること.
- これらのピケノファンの光物理的性質と構造動態を調査する.
主な方法:
- 5,8-ジブロモ-2,11-ディ-テルト-ブチルピケンのマルチグラムスケール合成
- ピケノファンのシリーズへの変換 (6-10).
- 管状 [2,2][5,8]ピケノファネディエンの構造分析のためのX線結晶学.
- バン対バンの逆転障壁の実験的推定.
- 超高速時間解像度放射スペクトロスコーピー
主要な成果:
- 異なるブリッジ構造を持つ新種のピケノファンの合成に成功した.
- X線構造は,シスエチレン結合のピケノファンの管状の形状を明らかにした.
- イソプロピル置換誘導体には18. 7 kcal/molの逆転障壁が決定された.
- 弱いエクシトン移位と二重放出 (エクシトンとエクシマー) を含む明確な光物理的行動が観察されました.
- エクシマー形成のメカニズムは,2つの状態の可逆反応で,構造的変形が速く (20 psの寿命) 解明された.
結論:
- ピケノファンの橋のわずかな構造変更は,光物理的性質を大幅に変化させる.
- ピケノファンは,種間反応の利用の可能性を示している.
- この研究は,複雑な π システムにおける分子構造,動力学,光物理学の関係に関する洞察を提供します.
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