ノンディスコイドメソゲンの新しい上部構造:3,4,5-トリアルコキシベンゾ酸アンヒドリドの半ディスク分子の不均等に並行した結合により,柱状の構造と,片方向に傾いたインターディジテーションが形成されます
Keiki Kishikawa1, Shigetaka Furusawa, Takahiro Yamaki
1Department of Materials Technology, Faculty of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
Journal of the American Chemical Society
|February 21, 2002
まとめ
新しい液体結晶酸アンヒドリドは,ユニークな柱状の相を形成します. これらの分子は,二極二極相互作用によって自己組み立てを行い,潜在的な螺旋構造を持つ一方向に交差した列を形成します.
科学分野:
- 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
- クリスタログラフィーです.
背景:
- ノンディスコイドメソゲンは,新しい液晶相の開発に不可欠である.
- 酸アンヒドリドは,以前は液晶化合物として調査されていませんでした.
- 分子自己組み立ての理解は,高度な材料の設計の鍵です.
研究 の 目的:
- 新規試験のコキシベンゾ酸アンヒドリドの設計と合成を行う.
- 液晶相におけるこれらの化合物の自己組立と上部構造を調査する.
- 極交点としての -CO-O-CO-部分の潜在能力を探求する.
主な方法:
- トライルコキシベンゾ酸アンヒドリドの合成 (化合物2-11).
- 偏光顕微鏡,微分スキャニング熱計,MM2/AM1計算,円形二重化スペクトロスコピー,X線微分を用いた特徴付け.
- 分子パッキングと相行動の分析.
主要な成果:
- 化合物5−9と11は,カルボニル基の二極二極相互作用によって,柱に自己集合した.
- 新しく一方向に数字を交わした柱状の相が観察され,その分子は柱の中に反パラレルに配置された.
- 円形の二重化スペクトルによって証明される,キラルなサイドチェーンを持つ化合物11の螺旋的な組織が示唆されました.
結論:
- トリアルコキシベンゾ酸アンヒドリドは,液晶酸アンヒドリドの第1級である.
- -CO-O-CO-部分は,柱状の構造に自己組み立てのための極交点として効果的に作用します.
- この研究は,一方向に数字を交わした柱状液晶相を作り出すための新しい方法を示しています.
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