高精度测量对同位素对非共价宿主-客相互作用的影响
Jeffrey S Mugridge1, Robert G Bergman, Kenneth N Raymond
1Department of Chemistry, University of California, Berkeley, and Chemical Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720-1460, USA.
Journal of the American Chemical Society
|January 7, 2010
概括
这项研究精确地测量了与超分子宿主结合的客分子的小平衡同位素效应. 化位置影响了结合强度,揭示了宿主与客人的相互作用中的微妙差异.
科学领域:
- 超分子化学 超分子化学
- 物理化学 物理化学
- 化学物理 化学物理
背景情况:
- 自组装的超分子宿主可以通过非共价相互作用与客体结合.
- 均衡同位素效应 (EIEs) 为结合相互作用提供了洞察力.
- 核磁共振定位是测量平衡常数的一种强大技术.
研究的目的:
- 精确测量EIE与超分子宿主的阴性客体结合.
- 为了研究客人代位置对主机-客人互动的影响.
- 为了证明NMR定位的适应性,以测量EIE在非共价系统.
主要方法:
- 使用了一个自组装的超分子宿主,[Ga(4) L(6) ](12-).
- 采用的NMR定位是根据酸度常数的方法进行调整的.
- 测量了与宿主外部结合的甲三甲基同位素的EIE.
主要成果:
- 准确地测量了非常小的EIE用于客人协会.
- 与环/位相比,在甲基处观察到较大的甲基化EIE.
- 在基于客C-H/D键位置的非共价相互作用中显示微妙的差异.
结论:
- 核磁共振定位方法是有效的测量EIEs在非共价宿主-客互动.
- 化位置显著影响微妙的非对应相互作用.
- 这种技术提供了一种通用方法,用于精确测量相对平衡常数.
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