光流体介質におけるアゾベンゼンの超分子キラリティを調節するための感覚と波長を持つ円状に偏光された光
Laibing Wang1,2, Lu Yin2, Wei Zhang2
1Graduate School of Materials Science, Nara Institute of Science and Technology , 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
Journal of the American Chemical Society
|August 29, 2017
まとめ
円形の偏光 (CPL) はアゾベンゼン分子のキラリティを誘導する. 波長だけでなく CPLの手性も 奇拉的な結果を左右し 分子奇拉性を制御します
科学分野:
- 写真化学
- 超分子化学
- ポリマー科学
背景:
- 円形の偏光 (CPL) は,非対称な光化学反応に影響を与える物理的な力として認識されています.
- CPLのハンドル性は伝統的に製品キラリティの唯一の決定因子と考えられています.
- CPLのハンド性,波長,照射時間が製品のキラリティにどのように影響するかについての体系的な研究は欠けている.
研究 の 目的:
- CPLのハンド性,波長,照射時間の誘発キラリティへの影響を体系的に調査する.
- アゾベンゼンを含むポリマーにおけるキラリティの生成,逆転,およびスイッチングを調査する.
- CPLで制御される分子とポリマーのヒラリティに関する新しい洞察を提供するためです.
主な方法:
- アキラルポリメタクリレートとアキラルアゾベンゼンの集積物を光流体媒介で利用した.
- 20秒間,CPL (313,365,405,436 nm) を単色で照射したサンプル.
- 理論的シミュレーションと 実験的観測を併用しました
主要な成果:
- アゾベンゼンキラリティで高い不対称性比 (±1.3 × 10−2) が得られ,周期的に生成され,逆転し,スイッチされた.
- CPL感覚とは独立して,照射波長を変えることで,光誘発キラリティを交換できることを示した.
- 暗闇で1週間以上 観察された光学活動の維持
結論:
- CPL誘発のアゾベンゼン積層のキラリティは,CPL感覚と波長の両方に依存する.
- この波長に依存するキラリティの制御は,コットン効果と同様の新しいメカニズムを提供します.
- 発見は,CPL駆動の分子およびポリマーシステムにおけるキラリティ制御の理解を進める.
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