在分离盐中溶解质子的分子结构. 短期,强,低壁垒 (SSLB) H债券
Daniel Stasko1, Stephan P Hoffmann, Kee-Chan Kim
1Department of Chemistry, University of California, Riverside, California 92521-0403, USA.
Journal of the American Chemical Society
|November 15, 2002
概括
新的碳酸离子使得稳定,有特征的化质子盐. 这些布伦斯特德酸为有机化学应用提供可调节的质子传递和增强的热稳定性.
科学领域:
- 无机化学 无机化学
- 超分子化学 超分子化学
- 物理化学 物理化学
背景情况:
- 碳酸阳离子是很大的,惰性,和弱的基础.
- 溶解质子盐在有机合成和催化过程中至关重要.
- 现有的质子源如[H(OEt(2)) ((2)][BAr(F) ]在热稳定性方面存在局限性.
研究的目的:
- 使用碳酸离子合成和表征新的化质子盐.
- 为了研究这些布伦斯特德酸的结构和特性.
- 为了比较它们的稳定性和酸度与现有的质子化剂.
主要方法:
- 碳酸离子的合成:CHB(11)R(5)X(6)(-) (R = H,Me;X = Cl,Br). 碳酸离子的合成方法是:
- 使用O原子供体溶剂,分离化质子盐[H(溶剂) ((x) ]][CHB ((11) R ((5) X ((6))) 的隔离和结构特征.
- 光谱分析 (IR) 和密度函数理论 (DFT) 的计算.
主要成果:
- 成功地分离和特征化了化质子与碳酸对子的盐.
- 与基于四乙酸的酸相比,证明了可调节的酸度和增强的热稳定性.
- 在[H(溶剂) ((2))) ((+)) 电离子中确定了短,强,低障碍 (SSLB) 的键.
- 观察到具有特征的扩大IR波段,表明SSLB的键.
结论:
- 碳酸离子为稳定的化质子Brønsted酸提供了强大的反.
- 对于有机溶剂来说,这些新型酸在质子传递和热稳定性方面具有优势.
- 结构和计算数据阐明了SSLB在质子溶剂中的键的性质.
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