通过异质核有机金属囊轻松分离区域性化合物
Wen-Ying Zhang1, Yue-Jian Lin1, Ying-Feng Han1
1Department of Chemistry, Fudan University , 220 Handan Road, 200433 Shanghai, China.
Journal of the American Chemical Society
|July 28, 2016
概括
研究人员开发了一种新型有机金属囊,能够从混合物中选择性地分离特定的异构体. 这一突破为使用尺寸,形状和银与pi的相互作用分离具有挑战性的区域异构化合物提供了一种新方法.
科学领域:
- 超分子化学
- 有机金属化学
- 同位体分离
背景情况:
- 由于有机分子具有相似的物理和化学特性,因此分离有机分子的结构异构体具有挑战性.
- 区域异构化合物的容易分离仍然是化学中的一个重大障碍.
研究的目的:
- 开发一种通用的有机金属囊,用于从混合物中选择性封装和分离特定的异构体.
- 研究开发的宿主-客人系统的分子识别能力和释放机制.
主要方法:
- 一个异金属有机金属囊的构造,具有两个银中心和两个四核[Rh4]金字塔.
- 对囊选择性封装各种衍生物的实验研究.
- 控制分子识别的力量分析,包括尺寸/形状匹配和Ag-π相互作用.
- 使用固体液体溶剂和光刺激释放客分子的演示.
主要成果:
- 有机金属囊选择性地封装混合物中的特定异构体,对各种类替代衍生物具有高度的特异性.
- 获得了对p-xylen,p-dichlorobenzene,p-dibromobenzene和p-diiodobenzene选择性封装的证据.
- 大小和形状的互补性以及Ag-π相互作用被确定为分子识别的关键因素.
- 封装的p-xylen通过溶剂洗释放,而其他客人则使用光释放.
结论:
- 开发的异金属有机金属囊作为选择性同位素封装的通用宿主.
- 该系统具有可调节的特异性,使其能够分离具有挑战性的区域异构体.
- 展示了有效的客人释放策略,包括溶剂洗和光刺激.
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