サイクルビス (エチニルヘリケーン) オリゴーマーから派生した自己組立型リオトロピク液晶系のダイナミック・リバーシブル・ポリモルフィズム
Nozomi Saito1,2, Kiyoshi Kanie3, Masaki Matsubara3
1†Frontier Research Institute for Interdisciplinary Sciences, Tohoku University , 6-3 Aoba, Sendai 980-8578, Japan.
Journal of the American Chemical Society
|May 6, 2015
まとめ
合成サイクルエチニルヘリセンのオリゴーマーが自己組み立てられ,ダイナミックな液体結晶になります. これらの分子は反転可能な多形性を示し,秩序付けられた液晶とゲル状態の間で移行します.
科学分野:
- 超分子化学 超分子化学
- マテリアルサイエンス 材料科学
- 有機化学 オーガニック・ケミストリー
背景:
- リョートロピック液晶 (LLC) は,高度な材料にとって不可欠です.
- 自己組み立てシステムにおけるポリモルフィズムを制御することは,重要な課題です.
- 合成分子は,自己組み立てのための調整可能な性質を提供します.
研究 の 目的:
- 新しい自己組み立てライオトロピク液晶 (LLC) システムを開発する.
- 合成分子におけるダイナミック・リバーシブル・ポリモルフィズムを研究する.
- 周期性エチニルヘリケンのオリゴマーの構造-性質関係を探求する.
主な方法:
- サイクルエチニルヘリケンのオリゴーマー (サイクロビス[(M) -D-n]) の合成.
- 温度と溶媒によって誘発される分子構造の変化の調査.
- 擬似アンチオメリックアサイクリックオリゴマーによる自己組み立て行動と複合体の形成の分析.
- 顕微鏡やその他の技術を使用して,液晶とゲル相の特徴づけ.
主要な成果:
- 周期性オリゴマーは,ランダムなコイルと分子内ホモダブルヘリックス間の構造的移行を示した.
- 三分子複合体の形成 (10,000 Da以上) は二分子複合体の形成に優勢であった.
- 高濃度での自己組み立てにより,アニゾトロピカルに並べられた繊維のLLCが生成され,ゲルを形成するアサイクリック系とは異なり.
- LLCとぼんやりとしたゲルの間の可逆的な熱色ポリモルフィズムが観察されました.
結論:
- ダイナミックで反転可能な多形性を持つ新しい自己組み立てLLCシステムが成功裏に開発されました.
- 周期的分子構造は,分子レベルからマクロスケープレベルへの集積を効果的に制御します.
- この研究は,完全に合成された分子システムにおける可逆的多形化の重要な例を示しています.
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