溶液中的素结合:二甲基与阳离子和未充电的易斯基的相互作用
Graham E Garrett1, Gregory L Gibson1, Rita N Straus1
1Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada.
Journal of the American Chemical Society
|March 18, 2015
概括
这项研究量化了溶液中的素结合,测量了二和易斯基之间的相互作用强度. 研究结果揭示了债券能量的趋势以及捐赠能力和静电潜力之间的关系.
科学领域:
- 超分子化学 超分子化学
- 非共价相互作用 非共价相互作用
- 有机化学 有机化学
背景情况:
- 素结合涉及缺乏电子的素 (Te,Se,S) 与易斯基相互作用.
- 在固体中,对素结合的证据很丰富,但溶液阶段的定量数据很少.
- 了解溶液相相互作用对于分子识别和材料科学中的应用至关重要.
研究的目的:
- 在有机溶剂中定量确定素结合相互作用的关联常数.
- 为了研究捐赠体,接受体和溶剂变异对素键强度的影响.
- 为了建立一个线性自由能量关系,素结合.
主要方法:
- 光谱技术包括UV-vis,1H NMR和19F NMR光谱.
- 电子喷雾电离质谱 (纳米-ESI-MS) 用于相互作用分析.
- 计算化学使用B97-D3函数用于理论验证.
主要成果:
- 对于与各种易斯基 (化物,酸盐,核氨酸) 结合的佐甲基的量化关联常数.
- 基于供体,受体和溶剂特性,观察到石墨烯键的自由能量明显趋势.
- 建立了捐赠能力和电静电位在中心之间的线性自由能量关系.
- 在实验自由能量和B97-D3分散校正计算之间显示出良好的一致性.
结论:
- 在溶液中,可以使用光谱和质谱法方法可靠量化素结合相互作用.
- 这项研究为溶液阶段的素结合提供了有价值的定量数据.
- 计算方法,特别是分散校正的DFT,可以准确地预测实验性素键强度.
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