在THF中使用s-BuLi或i-PrLi和奇拉胺的不对称脱:胺很重要
Giorgio Carbone1, Peter O'Brien, Göran Hilmersson
1Department of Chemistry, University of York, Heslington, York YO10 5DD, UK.
Journal of the American Chemical Society
|October 13, 2010
概括
这项研究使用NMR光谱学确定了复合物的结构. 一种新的 (+) - - 斯帕特因替代物使THF中的高度选择性非对称脱反应成为可能,这是有机化学的重大进步.
科学领域:
- 有机金属化学 有机金属化学
- 不对称的合成方法
- 频谱学是一种光谱学.
背景情况:
- 有机试剂在有机合成中至关重要.
- 在涉及有机的反应中控制立体化学仍然是一个挑战.
- 斯帕特因已被用作一种性联结体,但其有效性可能取决于溶剂.
研究的目的:
- 为了阐明异 (i-PrLi) 复合物的溶液结构与 (-) - 斯帕特因和 (+) - 斯帕特因替代物.
- 为了研究不同溶剂 (二甲基以太和THF) 的复杂化行为.
- 为了评估这些复杂物在不对称的脱质反应中的有效性.
主要方法:
- 溶液状态核磁共振 (NMR) 光谱,特别是 (6) Li 和 (13) C NMR.
- 用冷条件 (-80°C) 来进行结构确定.
- 进行了不对称的去反应,然后用电友捕获.
主要成果:
- 在乙烯中,i-PrLi/(−) - - 斯帕特因形成了异构体,而 (+) - - 斯帕特因替代物形成了同构体.
- 在THF中, (-) -sparteine显示出有限的复杂化,仅在高度时形成单体.
- 在THF中, (+) - 斯帕特因替代物很容易与i-PrLi形成单体,从而在随后的脱反应中产生高的反选择性.
结论:
- 复合物的溶液结构与性联体和溶剂有很大差异.
- 一种新的 (+) - - 斯巴特因替代品在THF中表现优异,用于不对称的脱质.
- 这项工作介绍了THF中使用有机/胺复合体的第一个高度选择性非对称的deprotonations.
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