チラルの結合サンゴ
Melissa Ball1, Brandon Fowler1, Panpan Li2,1
1†Department of Chemistry, Columbia University, New York, New York 10027, United States.
Journal of the American Chemical Society
|July 31, 2015
まとめ
研究者らは,電子ドナー (ビチオフェン) と受容体 (ペリレンダイミド) を交互に配合した新型のストレントマクロサイクルを開発した. これらの分子には独特のステレオアイソマーと,相互変換のための"分子内逆転"メカニズムがあります.
科学分野:
- 有機化学
- 超分子化学
- 材料科学
背景:
- 結合されたマクロサイクルは,超分子化学において極めて重要です.
- 特定の空洞と電子特性を備えたマクロサイクルを設計することは依然として課題です.
研究 の 目的:
- 緊張したコンジュガートマクロサイクルに新しいデザインモチーフを導入する.
- 電子ドナーと受容子の単位を交代してマクロサイクルを作成します.
- これらの新しいマクロサイクルの立体化学とダイナミクスを調査する.
主な方法:
- ビチオフェン (ドナー) とペリレンダイミド派生体 (受容体) を用いたA-B-A-Bパターンのマクロサイクル合成.
- ステレオ同位体分離のためのキラル高性能液体染色法 (HPLC).
- スペクトル解析と密度関数理論 (DFT) の計算.
主要な成果:
- 硫黄原子とペリレンダイミド π 面で覆われた持続的な円形の空洞を持つマクロサイクルの形成.
- 3つのステレオアイソマーがうまく分離したキラルとアキラル形態の存在.
- ステレオアイソメアの相互変換のための"分子内サマーサルト"メカニズムの観察.
- 広い可視吸収スペクトルとビチオフェンからペリレンダイミドへの光誘導電子移転
結論:
- 新しいデザインのモチーフは,複雑で,緊張した,結合されたマクロサイクルの構築を可能にします.
- 特定された"分子内逆転"メカニズムは,マクロサイクルダイナミクスへの洞察を提供します.
- これらのマクロサイクルは,分子内電子移転により興味深い光物理的特性を有しています.
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