使用固态-溶液平衡状态的螺旋式芳香胺中性诱导的切换
Hua Jiang1, Christel Dolain, Jean-Michel Léger
1Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607 Pessac, France.
Journal of the American Chemical Society
|January 30, 2004
概括
在螺旋式芳香胺中引入一个奇拉中心会改变螺旋手性之间的溶液平衡. 然而,这种性诱导在固态中失去了,为螺旋结构提供了新的控制.
科学领域:
- 超分子化学 超分子化学
- 有机化学 有机化学
- 奇拉性研究 奇拉性研究
背景情况:
- 众所周知,芳香性胺基具有稳定的螺旋形状.
- 控制这些螺旋结构的手性 (性) 对各种应用至关重要.
- 了解奇拉中心对螺旋平衡的影响是一个正在进行的研究领域.
研究的目的:
- 为了研究将R不对称中心引入芳香性橄胺体对其螺旋形状的影响.
- 为了确定这种奇拉中心如何影响溶液和固态中右手和左手螺旋之间的平衡.
- 探索螺旋性寡合体中控制手性的潜力.
主要方法:
- 合成具有R不对称中心的芳香性橄胺.
- 使用技术来确定螺旋偏好的溶液状态分析 (例如,NMR,循环二元化).
- 结晶研究用于分析固态结构.
主要成果:
- R不对称的中心显著地将平衡转移到溶液中的特定螺旋形状,形成二极体异构体 (R-P和R-M螺旋体).
- 尽管进行了溶液状态性诱导,但发现R-P和R-M螺旋在1:1的比率下共同结晶.
- 在溶液中观察到的奇拉尔诱导在固态中被有效地关闭.
结论:
- 引入一个单一的性中心可以极大地影响溶液中的螺旋手性.
- 固态包装力可以覆盖溶液状态性诱导,导致性晶体结构.
- 这种现象提供了一种独特的机制来控制或关闭螺旋性寡合体中的手性.
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