操纵溶解物核友性与室温离子液体进行处理.
Lorna Crowhurst1, N Llewellyn Lancaster, Juan M Pérez-Arlandis
1Contribution from the Department of Chemistry, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom.
Journal of the American Chemical Society
|September 16, 2004
概括
离子液体增强了氨基的核性,与它们对化物离子的禁用作用不同. 这种反应性差异主要是由于激活和溶剂结特性发生变化.
科学领域:
- 物理化学 物理化学
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
背景情况:
- 离子液体 (ILs) 是具有独特性质的可调节溶剂.
- 了解ILs对核友反应的影响对于合成化学至关重要.
- 在IL中,中性电荷核友的行为比离子核友的行为更少被探索.
研究的目的:
- 为了研究ILs对负荷中性氨基核的反应性的影响.
- 为了比较ILs中的氨基酸与分子溶剂中的氨基酸的核性.
- 阐明控制这些反应性变化的因素.
主要方法:
- 研究了 (n) 丁胺,二 (n) 丁胺和三 (n) 丁胺与甲基p-nitrobenzenesulfonate的反应.
- 使用了三个离子液体:[bmpy][N(Tf)(2)],[bmpy][OTf],和[bmim][OTf].
- 将ILs的反应性与二甲和乙烯的反应性进行比较;分析了Eyring激活参数和Kamlet-Taft溶剂参数.
主要成果:
- 与分子溶剂相比,所有研究的胺在离子液体中都表现出增强的核性.
- 离子液体使离子核友失活,与氨基的行为形成鲜明对比.
- 激活变化被确定为观察到的反应性趋势的主要驱动因素.
结论:
- 离子液体显著调节充电中性核的反应性.
- 在观察到的效应中,ILs和核之间的结相互作用起着关键作用.
- ILs对充电与中性核友的独特影响突出了它们复杂的溶解行为.
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