C2対称キラル [60]フルレネ-バイサドクトのC2対称キラル
Tatsuya Nishimura1, Kayo Tsuchiya, Sousuke Ohsawa
1Contribution from the Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University, Chikusa-ku, Nagoya 464-8603, Japan.
Journal of the American Chemical Society
|September 16, 2004
まとめ
チラルフルレンビサドクトは,ポリマーにヘリシティを誘導するために使用されました. 一つの特定のバイサドクト構造のみが,ポリマーの片手ヘリックス形成を効果的に促進し,分子幾何学に対する感受性を示した.
科学分野:
- 超分子化学 超分子化学
- ポリマーサイエンスの科学
- 有機化学 オーガニック・ケミストリー
背景:
- キラルマクロモレキュルは,キラル認識と非対称な触媒を含む様々な用途に不可欠です.
- フーラーレンは,新しい超分子構造を作り出すための多用途な構成要素です.
- ポリマーの形状を制御することは,材料の特性を調整するために不可欠です.
研究 の 目的:
- マクロ分子ヘリシティ誘導体としてのキラルC(60) -ビサドクトの可能性を調査する.
- ポリマーヘリシティを誘導する際の異なるバイサドクト幾何学の構造-活性関係を探求する.
- 溶液中のアニオン型ポリ (フェニルアセチレン) の形状の変化に対するカチオン型フルレン誘導体の影響を調べる.
主な方法:
- キラルHPLCを用いたN-メチルフルロピロリジンビサダクトの合成とキラル解像度.
- 光学的に活性な,カチオン性C60) -ビサドクトの製造.
- アニオニックペンダントグループ (ポリ-1) を有するポリフェニルアセチレン (poly-phenylacetylene) とのC(60) -バイサドクトの複合.
- ポリマーの形状を監視するために,紫外線で可視化および円形の二重化 (CD) を含む光譜分析.
主要な成果:
- 3つのキラルなN-メチルフルロピロリジンバイサドクトが合成され,エナティオマーに分解されることに成功した.
- ポリ-1との複合化では,トランス-3バイサドクトのみが,紫外線で見える領域において,有意な誘発型円形二重化 (ICD) を誘導した.
- トランス-2およびシス-3バイサドクトは最小限のCD誘導を示し,限られたヘリシティ形成を示した.
- 観測されたヘリシティ誘導は,C ((60)) -バイサドクトの特定の構造と幾何学に大きく依存していた.
結論:
- チラルC ((60)) -ビサドクトは,ポリ ((フェニラセチレン) 誘導体の有効なマクロ分子ヘリシティ誘導体として作用することができます.
- ヘリシティ誘導の効率は,フルレンバイサドクト内の電荷のステレオ化学と空間的配置に敏感です.
- この研究は,ポリマーの二次構造を制御するための,量身のフルレン誘導体の可能性を強調しています.
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