螺旋型のエチニルヘリセンのオリゴマーの展開速度に対する芳香剤の顕著な効果
Hiroki Sugiura1, Yasuko Nigorikawa, Yuto Saiki
1Department of Organic Chemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba, Sendai 980-8578, Japan.
Journal of the American Chemical Society
|November 13, 2004
まとめ
光学的に活性なエチニルヘリセンのオリゴマーは,溶液に展開する螺旋状の構造を形成します. 展開速度は,溶媒の芳香性特性に大きく依存し,溶媒の柔らかさと相関しています.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 超分子化学 超分子化学
- スペクトル顕微鏡検査です.
背景:
- アサイクリックエチニルヘリケンのオリゴマーは,ソノガシラ結合とデプロテクションを使用して合成されます.
- 円形の二重化 (CD) のスペクトルなどのキロプティックな性質は,螺旋構造の特徴づけに不可欠です.
研究 の 目的:
- 光学的に活性なアサイクルエチニルヘリケンのオリゴーマーを合成する.
- 螺旋状とランダムなコイル形状の間の構造的移行を調査する.
- 様々な溶媒における螺旋構造の展開速度に影響を与える要因を決定する.
主な方法:
- ソノガシラカップリングとデプロテクションを含む双方向合成.
- 円形の二重化 (CD) スペクトロスコピーは,螺旋状およびランダムなコイル構造を分析します.
- オリゴマーの集積状態を研究するための蒸気圧オスモメトリ.
主要な成果:
- 光学的に活性なアサイクリックエチニルヘリセンのオリゴマーの高収量が得られた.
- 7つ以上のヘリケーンを持つオリゴーマーが螺旋状の構造を形成し,短いものはランダムなコイル形状を採用しました.
- 螺旋ヘプタマーは,クロロフォームでランダムなコイルに展開し,展開速度は,芳香溶媒の置換剤に大きく依存し,大きさの7つの順序によって異なります.
- 展開速度は,アレン溶媒の絶対硬さと相関しており,より柔らかいアレンがより速い展開を促進します.
- 蒸気圧オスモメトリーは,いくつかの溶媒では二次元螺旋構造,他の溶媒では単体ランダムコイル構造を示した.
- ランダムなコイル溶液の濃縮時に螺旋構造の再生が観察されました.
結論:
- 光学的に活性なアサイクリックエチニルヘリセンのオリゴーマーには,長さに基づいて独特の螺旋状およびランダムなコイル構造があります.
- 溶媒の特性,特に芳香代替剤の電子およびステリック要因は,螺旋構造の安定性と展開ダイナミクスに大きな影響を与えます.
- 観察された構造-溶媒の相互作用は,応答性分子システムの設計に関する洞察を提供します.
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