在水凝中选择性增长和晶体反体的分布
Rositza I Petrova1, Jennifer A Swift
1Department of Chemistry, Georgetown University, 37th and "O" Streets NW, Washington, DC 20057-1227, USA.
Journal of the American Chemical Society
|January 30, 2004
概括
酸 (NaClO3) 的奇拉结晶可以使用 agarose凝来控制. 修改凝条件,如密度和温度,可以选择性地设计特定反体的生长,从而实现d-和l-NaClO3晶体的显著反体过量 (ee).
科学领域:
- 结晶科学是结晶的科学.
- 奇拉性研究研究.
- 材料科学是一种材料科学.
背景情况:
- 酸 (NaClO3) 在结晶后表现出自发的性,从无溶液过渡到性固体形式.
- NaClO3的纯水性结晶导致d-和l-反体的均分布.
- 阿加洛斯凝是一种性多糖,可以影响NaClO3晶体的反选择性.
研究的目的:
- 为了研究阿加罗斯凝特性对酸 (NaClO3) 晶体的反体过量 (ee) 的影响.
- 确定凝密度,温度和辅溶剂扩散如何影响d-和l-NaClO3.3的选择性结晶.
- 为了证明在NaClO3结晶中设计enantiomorph偏差的方向和大小的能力.
主要方法:
- 进行了752个凝介导结晶实验,共使用12,384个单独的NaClO3晶体.
- 改变了阿加罗斯凝密度 (0.1-0.75 wt %),温度 (6°C和 24°C),并将甲醇作为辅溶剂.
- 分析统计数据以量化反体过量 (ee) 并确定晶体分布的趋势.
主要成果:
- 在6°C的水性阿加罗斯凝有利于d-NaClO3的生长,在高凝度下达到22%.
- 在甲醇扩散下的晶体生长有利于l-NaClO3.
- 较高的温度增强了enantiomorph偏差;在24°C与甲醇,l-NaClO3的增长达到53% ee.
- 凝条件选择性地控制了enantiomorph偏差的大小和方向.
结论:
- 糖凝的特性和实验条件 (温度,辅溶剂) 可以被操纵,以选择性地产生酸的d或l-enantiomers.
- 观察到的偏差归因于阿加罗斯构造和凝-晶体表面相互作用的变化,这些相互作用影响了反体的抑制.
- 这提供了一种通过受控的凝介导结晶的工程性晶体形成的方法.
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