溶剂和客同位素对α,β和6-amino-6-deoxy-β-cyclodextrins的复合热力学的影响
Mikhail V Rekharsky1, Yoshihisa Inoue
1Entropy Control Project, ICORP, JST, 4-6-3 Kamishinden, Toyonaka 560-0085, Japan.
Journal of the American Chemical Society
|October 10, 2002
概括
与水相比,氧化物增强了环氧的复杂化亲和力,充电的客人显示出更大的影响. 减肥的客人由于C-D债券特性而表现出较低的亲和力.
科学领域:
- 超分子化学 超分子化学
- 物理化学 物理化学
- 生物物理化学 生物物理化学
背景情况:
- 环极素 (CDs) 是各种应用中至关重要的宿主分子.
- 了解不同溶剂中的客主互动对于优化基于CD的系统至关重要.
- 溶剂效应,特别是H2O与D2O,可以显著影响结合热力学.
研究的目的:
- 量化 H2O 和 D2O 中不同客体的循环德克斯特林复合的热力学参数.
- 研究客人中替代对复杂化行为的影响.
- 阐明水化和溶剂特性在客宿主亲和关系中的作用.
主要方法:
- 使用定位微热量计来确定结合常数 (K),度 (ΔH°) 和度 (TΔS°) 的变化.
- 复杂化研究使用原生和修改的环氧素与中性,充电和减肥的客人进行.
- 实验是在酸盐缓冲溶液中进行的,pH/pD为6.9和298.15K.
主要成果:
- 与H2O相比,D2O的复杂化亲属性 (K) 在化和非化客人中始终高出5-20%.
- 在D2O中增强的亲和力与客人的水大小和强度相关;充电的客人显示较小的K (H2O) /K (D2O) 比率.
- 减肥客人在两种溶剂中表现出比非减肥客人低5-15%的亲和力,这归因于C-D键特性.
结论:
- 溶剂的同位素效应显著影响循环德克斯的复合热力学.
- 水的特性是H2O和D2O之间的亲和力差异的关键决定因素.
- 客体的化通过改变的电子和范德瓦尔斯相互作用影响结合,观察到的形状变化最小.
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