在DMSO中制成粉末的KOH:通过对环境温度的奇拉性记忆来实现不对称循环的有效基础
Takeo Kawabata1, Katsuhiko Moriyama, Shimpei Kawakami
1Institute for Chemical Research, Kyoto University Uji, Kyoto 611- 0011, Japan. kawabata@scl.kyoto-u.ac.jp
Journal of the American Chemical Society
|February 29, 2008
概括
在DMSO中的氧化粉末能够在室温下形成高度反选择性的C-C键. 与传统的低温无水条件相比,这种方法取得了优异的结果,用于制造性酸中介物.
科学领域:
- 有机化学 有机化学
- 不对称的合成方法
背景情况:
- 酸盐化学对于立体选择性碳-碳键形成至关重要.
- 传统方法通常需要无水溶剂和低温使用金属胺基.
研究的目的:
- 研究一种用于不对称的分子内C-C键形成的新方法.
- 探索在二甲基硫氧化物 (DMSO) 中使用粉状氧化物 (KOH) 作为酸盐生成的基础.
主要方法:
- 在干燥和潮湿的DMSO中利用粉状KOH作为基础.
- 通过轴性性酸中介物研究了不对称的分子内C-C键形成.
- 与使用六甲基伊尔迪西拉齐德在低温下DMF中的传统方法相比,对抗选择性.
主要成果:
- 在20°C时达到高达99%的反体过量 (ee).
- 证明了比传统方法更高的抗选择性.
- 估计,拉乙烯酸中间体的种族化屏障大约为15.5kcal/mol.
结论:
- 在DMSO中的粉末KOH是不对称的酸盐化学的有效和高效的基础.
- 高选性归因于生成的性酸中介的快速循环.
- 这一发现为立体选择性C-C键形成提供了一个实用且可能更容易获得的途径.
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