氧超基作为非极性溶剂中极性结合口袋的氧超基
Lucie Ducháccková1, Aneta Kadlccíková, Martin Kotora
1Department of Organic Chemistry, Charles University in Prague, Hlavova 8, 12843 Prague 2, Czech Republic.
Journal of the American Chemical Society
|August 21, 2010
概括
基于2.2'-双基-N,N'-二氧化物的新型性超基,表现出高质子亲缘关系. 它们独特的结构稳定了非极性溶剂中的极性中间体,使新的催化反应成为可能.
科学领域:
- 有机化学 有机化学
- 超分子化学 超分子化学
- 催化剂是一种催化剂.
背景情况:
- 开发具有独特结构特征的新型有机基对于推进化学合成至关重要.
- 状分子为立体选择性转换提供了独特的机会.
- 2,2'-双-N,N'-二氧化物衍生物以它们的协调特性而闻名.
研究的目的:
- 为了引入一个新的类型的性超基,从2.2'-bipyridyl-N,N'-二氧化物骨架衍生.
- 研究这些新型超基的质子亲和力和结合方式.
- 为了证明它们在有机反应中作为催化剂的实用性.
主要方法:
- 基于2,2'-双基-N,N'-二氧化物支架的新型性超基的合成.
- 试验性确定质子亲和力.
- 计算研究 (理论数据) 以阐明质子位点和结合机制.
- 在催化合反应中的应用.
主要成果:
- 这些新型超基体表现出高质子亲缘关系 (约. 1050 kJ 摩尔 () 的
- 在氧原子中以化方式发生质子化.
- 超级基具有性结构,在疏水膜内有一个极结合点.
- 在非极性溶剂中观察到极性中间体和过渡结构的有效稳定.
- 甲和基酸之间的合反应的成功催化.
结论:
- 合成了一种具有特殊质子亲缘关系的新类性超基.
- 独特的结构图案允许在非极性介质中有效稳定反应性中间体.
- 这些超级基体代表了对不对称催化物的有希望的新工具.
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