1,8-Bis ((hexamethyltriaminophosphazenyl) 纳,HMPN:一种超基本的双"质子海绵"
Volker Raab1, Ekaterina Gauchenova, Alexei Merkoulov
1Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, 35032 Marburg, Germany.
Journal of the American Chemical Society
|November 10, 2005
概括
一种新型的超基,HMPN,结合了和甲结构,表现出前所未有的基本性. 这种质子海绵比DMAN基本的10^11倍以上,这是由于其独特的结构和分子内键.
科学领域:
- 有机化学 有机化学
- 超分子化学 超分子化学
背景情况:
- 开发强有机基对于各种化学应用至关重要.
- 质子海绵,如1,8-bis(dimethylamino) naphthalene (DMAN),以其高的基本性而闻名.
- 斯韦辛格的基代表了另一类有力有机基.
研究的目的:
- 通过结合素和1,8-甲结构图案,合成和表征一种新的超基.
- 评估新型化合物的基本性,并将其与现有的质子海绵和基相比较.
- 阐明有助于增强基本性的结构和电子因素.
主要方法:
- 新型化合物HMPN的合成和完整表征.
- 使用X射线晶体学确定HMPN及其结合酸的空间结构.
- 质子亲和力 (PA) 和密度函数理论 (DFT) 计算的理论估计.
- 测量pK (((BH+) 在乙基 (MeCN) 中的含量.
主要成果:
- 一种新的超基,HMPN,已成功合成和表征.
- HMPN具有异常高的基本性,其理论PA为274 kcal/mol,测量pK ((BH+) (MeCN) 为29.9.
- HMPN比1,8-bis(dimethylamino) naphthalene (DMAN) 的10 ^ 11倍以上的基础性.
- X射线结晶学和DFT计算揭示了一个不对称的分子内桥在HMPN的单质子形式.
- DFT的计算证实,高度源于中性的能量含量和酸中的分子内键.
结论:
- 酸和1,8-甲结构的组合产生了一个高度有效的超基.
- 结合酸中的分子内键对HMPN增强的基本性有显著的贡献.
- 在质子海绵类中,HMPN代表了一个新的基准,在基本性方面超过了现有的化合物.
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