完全に結合された平面ヘテロサイクリック [9] サーキュレン
Stephan K Pedersen1, Kristina Eriksen1, Hans Ågren2,3
1Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark.
Journal of the American Chemical Society
|August 14, 2020
まとめ
研究者は,新しいマクロサイクル芳香化合物である最初の [9] サーキュレンを合成し,サーキュレンの構造の既知の限界を広げました. この突破は材料科学と有機化学に 新たな可能性をもたらします
科学分野:
- 有機化学
- 材料科学
- 超分子化学
背景:
- 完全芳香 [n] サーキュレンは,マクロサイクル芳香炭水化物であり,以前は最大8つの芳香環 (n=8) に制限されていた.
- 高級 [n] サーキュレンの合成 (n>8) は有機化学の未知の領域でした.
研究 の 目的:
- 以前知られているn=8の限界を超えた新しい,より高次元の[n]サーキュレンを合成し,特徴づける.
- これらの新しいマクロサイクルシステムの構造的,電子的,芳香的性質を調査する.
主な方法:
- 3,6-二酸化炭素塩素とグリオクサルの間の高収量二酸化凝縮反応がマクロサイクル構築に使用された.
- 合成された [9] サーキュレンの正確な3次元構造を決定するために,単一結晶X線 difraktionが使用されました.
- 核独立化学シフト (NICS) と誘導電流密度 (ACID) のアニソトロピーの計算は,芳香性と電子特性を評価するために行われました.
主要な成果:
- 最初の [9] サーキュレン (diazatrioxa [9] サーキュレン) と [10] サーキュレン アナログ (tetrahydro-diazatetraoxa [10] サーキュレン) が成功して合成されました.
- X線解析により, [9] サーキュレンは完全に平らで,長方形のベンゼン環があり,ストレスの誘発による平らさを示唆しています.
- 中央の非芳香環における交互の結合長とパラトロピクリング電流は,有意な [9] 放射性エレンの共鳴貢献と誘発されたパラトロピク性を示す.
結論:
- 最初の [9] サーキュレンの成功合成は,マクロサイクル芳香化合物の分野における重要な進歩を表しています.
- 平面性および放射性特性を含む構造および電子特性は,ストレートなアロマティックシステムの振る舞いに関する新しい洞察を提供します.
- ノンアロマティックなコアにおける観測された誘発性パラトロピシティは,高度な材料における新しい電子的および光物理的特性を探求するための道を開く.
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