ダブル [7]ヘテロヘリセンの合成,構造,およびキロプティック特性
Xiao-Ye Wang1, Xin-Chang Wang2, Akimitsu Narita1
1Max Planck Institute for Polymer Research , Ackermannweg 10, 55128 Mainz, Germany.
Journal of the American Chemical Society
|September 23, 2016
まとめ
研究者たちは新しい二重ヘテロヘリケンを合成し 六つ構成の環で報告された最大のヘテロヘリケンを合成しました 独特の歪んだ構造は,例外的なキラル安定性と高い異体化障壁を提供します.
科学分野:
- 有機化学
- 超分子化学
- 材料科学
背景:
- ヘリケンは独特の螺旋構造を持つキラル分子です.
- 二重ヘリケンは構造的に複雑で,高度な応用の可能性を高めています.
- 複雑な有機分子で高いキラル安定性を達成することは依然として大きな課題です.
研究 の 目的:
- 6つの環を組み立てた 巨大な二重ヘテロヘリケンを合成する
- 合成された分子の構造的,電子的,そして光学的な性質を調査する.
- 二重ヘリケンのシステムにおけるキラル安定性の新しい基準を確立する.
主な方法:
- 合成のためのタンデム脱メチル化-ボリレーション反応.
- 構造の解明のための単一結晶X線微分
- アイソマー分離のためのキラル高性能液体染色法 (HPLC).
- アイソメリゼーションバリア分析のための理論的計算.
主要な成果:
- 11a,25a-dibora-11,12,25,26-tetraoxatetranaphtho[1,2-a:2',1'-f:1′′,2′′-j:2′′′,1′′′-o]ペリレンという二重 [7]ヘテロヘリケンの合成に成功しました.
- X線解析による分子内π層の高度な歪んだ構造の実証.
- 卓越したキラル安定性を示す最高理論的異体化障壁 (45.1 kcal/mol) の決定.
- (P,P) -と (M,M) -イソマーの分離と,対極の円形二重化を含む,それらの異なったキロプティックな性質の特徴づけ.
結論:
- 合成された二重ヘテロヘリケンは,これまでに報告された最大の6つ構成のリングシステムです.
- この分子は,独特の歪んだ形状により,驚くべき構造的硬さと高いキラル安定性を表しています.
- この研究は,分子認識とエナチオ選択的触媒の潜在的応用を持つ高度なキラル材料の開発のための新しいプラットフォームを提供します.
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