对可回氧切换的树脂素[4]arene 洞形素的键受体的评估
Igor Pochorovski1, Jovana Milić, Dušan Kolarski
1Laboratorium für Organische Chemie, ETH Zürich , Hönggerberg, HCI, 8093 Zürich, Switzerland.
Journal of the American Chemical Society
|February 27, 2014
概括
研究人员设计了一种基于碳胺的新型分子篮子,能够选择性地结合客人. 这种可氧化还原切换的腔体通过结合稳定了其封闭的花瓶形状,使得可控的客体封装和缓慢释放动力学成为可能.
科学领域:
- 超分子化学 超分子化学
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
背景情况:
- 洞穴体是宏循环宿主,以其封装客分子的能力而闻名.
- 通过外部刺激控制腔体构成和客体结合是超分子化学的一个关键挑战.
- 氧化回应系统为分子识别和封装提供可调节的特性.
研究的目的:
- 为了研究键受体组在resorcin[4]arene中诱导构造性切换的cavitands.
- 设计和合成一个可回氧切换的分子篮子,用于选择性客体封装.
- 为洞穴和系统中有效的键接受器制定设计准则.
主要方法:
- 合成二基-二基诺素复苏素[4]与各种键受体组的阿伦腔体.
- 在氧化还原相互转换时,风和花瓶形式之间的形状转换的评估.
- 制备和表征一个基于三基的篮子,利用最佳的碳胺受体.
- 使用梅西-d12.2中合成的篮子对小分子客体进行约束性研究.
主要成果:
- 碳胺被确定为最有效的键受体,用于稳定降低化状态下的花瓶形状.
- 一个基于三烯的篮子成功合成,证明了客人在其封闭的花瓶形状中完全无菌封装.
- 篮子表现出强大的结合 (关联常数高达10^4 M^-1) 和缓慢的客人交换动力学 (半衰期~10^4秒).
结论:
- 键受体设计对于控制体中氧化还原诱导的形状变化至关重要.
- 开发的基于三基的篮子代表了可切换的宿主-客人化学的重大进步.
- 该系统显示出需要受控分子封装和释放的应用的潜力.
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